{ "ProductData": { "ID": "CPS_000163", "ProductType": "Others", "BrandName": "LPA2", "ProductNameAddition": "Tina-quant Lipoprotein (a) Gen.2", "RegulatoryDisclaimer1": "For in vitro diagnostic use.", "DisclaimerGroup1": "IVD", "RegulatoryDisclaimer2": null, "DisclaimerGroup2": null, "RegulatoryDisclaimer3": null, "SampleType": [ "Plasma", "Serum" ], "LicenseDisclaimers": [ ], "RelatedLinks": "", "Clone": "", "ControlTissue": [ "" ], "ISOtypes": "", "Species": [ "" ], "StainLocalization": [ "" ], "ProductNameGlobal": "LPA2" }, "ProductImageDetails": { "ImagePath": "https://pim-media.roche.com/Images/Article_05852625190_im_en.png", "ImageType": "Image main" }, "Product2Taxonomy": { "Product2TaxonomyReferences": [ { "StructureSystemIdentifier": "Product_Grouping", "StructureSystemName": "Product Grouping", "NodeID": "01-0403", "StructureNodeStatus": "Active", "NodeName": "cobas Lipoprotein a" }, { "StructureSystemIdentifier": "OWP_Product_Types", "StructureSystemName": "Product Types", "NodeID": "20-000-00", "StructureNodeStatus": "Active", "NodeName": "Assays Reagents and Strips" }, { "StructureSystemIdentifier": "Lab_Type", "StructureSystemName": "Lab Types", "NodeID": "050-00", "StructureNodeStatus": "Active", "NodeName": "Core Lab" }, { "StructureSystemIdentifier": "Product_Solutions", "StructureSystemName": "Product Solutions", "NodeID": "020", "StructureNodeStatus": "Active", "NodeName": "Clinical Chemistry" }, { "StructureSystemIdentifier": "Health_Topics", "StructureSystemName": "Health Topics", "NodeID": "10-00-00", "StructureNodeStatus": "Active", "NodeName": "Cardiology" }, { "StructureSystemIdentifier": "Applications", "StructureSystemName": "Applications", "NodeID": "99-00-00", "StructureNodeStatus": "Inactive", "NodeName": "" }, { "StructureSystemIdentifier": "OWP_Techniques", "StructureSystemName": "Techniques", "NodeID": "999-00", "StructureNodeStatus": "Inactive", "NodeName": "" }, { "StructureSystemIdentifier": "OWP_Family", "StructureSystemName": "Product Families", "NodeID": "370", "StructureNodeStatus": "Active", "NodeName": "Tina-quant" }, { "StructureSystemIdentifier": "Pathogens", "StructureSystemName": "Pathogens", "NodeID": "99-00-00", "StructureNodeStatus": "Inactive", "NodeName": "" }, { "StructureSystemIdentifier": "Disease_Areas", "StructureSystemName": "Disease Areas", "NodeID": "99-00-00", "StructureNodeStatus": "Inactive", "NodeName": "" }, { "StructureSystemIdentifier": "Indications", "StructureSystemName": "Indications", "NodeID": "94", "StructureNodeStatus": "Active", "NodeName": "Cardiology" }, { "StructureSystemIdentifier": "OWP_Family", "StructureSystemName": "Product Families", "NodeID": "622", "StructureNodeStatus": "Active", "NodeName": "COBAS INTEGRA" } ] }, "Product2Materials": { "P2MaterialReferences": [ { "MaterialNum": "08106126190", "MaterialDescription": "LPA2, 150T, cobas c pack green", "RegisteredProductName": "LPA2", "GTIN": "07613336140833", "ProductCategoryText": "Reagents, kits", "OldMaterialNumber": "", "PackSizePIM360": "150 tests", "PackSizeDescPIM360": "cobas c 303/503", "MaterialAnnotation": "", "ReadyForUse": "true", "OrderInformation": "" }, { "MaterialNum": "05852633190", "MaterialDescription": "LPA Gen.2, 200Tests cobas c 701", "RegisteredProductName": "LPA2", "GTIN": "04015630930586", "ProductCategoryText": "Reagents, kits", "OldMaterialNumber": "", "PackSizePIM360": "200 tests", "PackSizeDescPIM360": "cobas c 701/702", "MaterialAnnotation": "", "ReadyForUse": "true", "OrderInformation": "" }, { "MaterialNum": "05852625190", "MaterialDescription": "LPa Gen.2, 150Tests cobas c/INT", "RegisteredProductName": "LPA2", "GTIN": "04015630929962", "ProductCategoryText": "Reagents, kits", "OldMaterialNumber": "", "PackSizePIM360": "150 tests", "PackSizeDescPIM360": "COBAS INTEGRA 400 Plus, cobas c 311/501/502", "MaterialAnnotation": "", "ReadyForUse": "true", "OrderInformation": "" } ] }, "Product2Products": { "Product2ProductReference": [ { "ProductID": "INS_2177", "BrandName": "cobas® c 702 module", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "2492", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 702", "StructureGroupName": "cobas c 702", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" } ] }, { "ProductID": "INS_6347", "BrandName": "cobas® c 303 analytical unit", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "9493", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 303", "StructureGroupName": "cobas c 303", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" } ] }, { "ProductID": "INS_2043", "BrandName": "cobas® c 311 analyzer", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "308", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 311", "StructureGroupName": "cobas c 311", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "560", "StructureGroupPath": "cobas 4000", "StructureGroupName": "cobas 4000", "StructureNodeStatus": "Active" } ] }, { "ProductID": "INS_338", "BrandName": "cobas® c 501 module", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "309", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 501", "StructureGroupName": "cobas c 501", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "679", "StructureGroupPath": "cobas 6000", "StructureGroupName": "cobas 6000", "StructureNodeStatus": "Active" } ] }, { "ProductID": "INS_501", "BrandName": "cobas® c 701 module", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "310", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 701", "StructureGroupName": "cobas c 701", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" } ] }, { "ProductID": "INS_2113", "BrandName": "cobas® c 502 module", "ProductNameAddition": "", "ReferenceType": "Instrument", "Classification": [ { "IdentifierofStructureSystem": "1", "NameofStructureSystem": "GPCH", "StructureNodeID": "2324", "StructureGroupPath": "ClinChem fully automated->Systems / Digital Products->cobas c systems->cobas c 502", "StructureGroupName": "cobas c 502", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "OWP_Product_Types", "NameofStructureSystem": "Product Types", "StructureNodeID": "10-000-00", "StructureGroupPath": "Analyzer Instruments and Systems", "StructureGroupName": "Analyzer Instruments and Systems", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Lab_Type", "NameofStructureSystem": "Lab Types", "StructureNodeID": "050-00", "StructureGroupPath": "Core Lab", "StructureGroupName": "Core Lab", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Product_Solutions", "NameofStructureSystem": "Product Solutions", "StructureNodeID": "020", "StructureGroupPath": "Clinical Chemistry", "StructureGroupName": "Clinical Chemistry", "StructureNodeStatus": "Active" }, { "IdentifierofStructureSystem": "Applications", "NameofStructureSystem": "Applications", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Techniques", "NameofStructureSystem": "Techniques", "StructureNodeID": "999-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Disease_Areas", "NameofStructureSystem": "Disease Areas", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Pathogens", "NameofStructureSystem": "Pathogens", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "Health_Topics", "NameofStructureSystem": "Health Topics", "StructureNodeID": "99-00-00", "StructureGroupPath": "", "StructureGroupName": "", "StructureNodeStatus": "Inactive" }, { "IdentifierofStructureSystem": "OWP_Family", "NameofStructureSystem": "Product Families", "StructureNodeID": "614", "StructureGroupPath": "cobas c", "StructureGroupName": "cobas c", "StructureNodeStatus": "Active" } ] } ] }, "ProductSpec": [ { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0108106126190c503", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "3", "DocumentObjectID": "FF000000047A7B0E", "DocumentOriginID": "FF0000000306820E", "MaterialNumbers": [ "08106126190" ], "InstrumentReferences": [ { "ID": "8481", "BrandName": "cobas c 503" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on Roche/Hitachi cobas c systems.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle enhanced immunoturbidimetric assay.

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.

Human lipoprotein (a) agglutinates with latex particles coated with anti‑Lp(a) antibodies. The precipitate is determined turbidimetrically at 800 / 660 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

Measuring range: 7‑240 nmol/L

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank

= 6 nmol/L

Limit of Detection

= 7 nmol/L

Limit of Quantitation

= 20 nmol/L

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 20 %. It has been determined using low concentration lipoprotein (a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The European Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

However the NHLBI recommends to stop using data for total Lp(a) mass, and to use nmol/L units instead, which consider the number of particles. Additionally they recommend to use assays independent from apo(a) size and standardized according to the IFCC reference material SRM2B.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Based on the evaluation of Framingham data values above 75 nmol/L are regarded as a cut‑off value for the presence of an increased risk.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Elevated Lp(a) levels can be found in most racial/ethnicity groups, with the prevalence being lowest in whites and Asians. The median Lp(a) levels in black subjects and in Asian Indians from southern locations are 2‑ to 4‑fold higher compared with whites, and up to 68 % of blacks have Lp(a) levels > 75 nmol/L, whereas levels above this threshold are present in around 25 % of whites.

LREFTsimikas S, Clopton P, Brilakis ES, et al. Relationship of Oxidized Phospholipids on Apolipoprotein B-100 Particles to Race/Ethnicity, Apolipoprotein (a) Isoform Size, and Cardiovascular Risk Factors: Results From the Dallas Heart Study, Circulation 2009 Apr;119(13):1711-1719.

Therefore reference ranges have not been established for this assay for different ethnic populations or disease states. Since Lp(a) levels are largely influenced by hereditary factors and vary with ethnic populations it is recommended that each laboratory establish own expected values.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations – interference

Criterion: Recovery within ± 6 nmol/L of initial values of samples ≤ 60 nmol/L and within ± 10 % for samples > 60 nmol/L.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference from rheumatoid factors up to a concentration of 1200 IU/mL.

Plasminogen: No significant cross‑reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross‑reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 450 nmol/L.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on cobas c systems. All special wash programming necessary for avoiding carry-over is available via the cobas link. The latest version of the carry-over evasion list can be found with the NaOHD/SMS/SCCS Method Sheet for information. For further instructions refer to the operator’s manual.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

OrderInformation (CC Reagents - cobas + Integra)

Analyzer(s) on which cobas c pack(s) can be used

08106126 190

Tina‑quant Lipoprotein (a) Gen.2 (150 tests)

System‑ID 2086 001

cobas c 503

Materials required (but not provided):

05852641 190

Preciset Lp(a) Gen.2 (5 × 1 mL)

Codes 20962‑20966

05852650 190

PreciControl Lp(a) Gen.2
Level Low (2 × 1 mL)
Level High (2 × 1 mL)


Code 20137
Code 20138

08063494 190

Diluent NaCl 9 % (123 mL)

System‑ID 2906 001

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

LPA2: ACN 20860

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum and plasma

Test definition

Reporting time

10 min

Wavelength (sub/main)

800/660 nm

Reagent pipetting

Diluent (H2O)

R1

100 µL

R3

25 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

1.5 µL

Decreased

6.0 µL

8 µL

88 µL

Increased

1.5 µL

For further information about the assay test definitions refer to the application parameters screen of the corresponding analyzer and assay.

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

26 weeks

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrators

S1: H2O
S2‑S6: Preciset Lp(a) Gen.2

Calibration mode

Non-linear

Calibration frequency

Automatic full calibration
- after reagent lot change

Full calibration
- as required following quality control procedures

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against the IFCC reference material SRM2B for nmol/L.

LREFMarcovina SM, Albers JJ, Scanu AM, et al. Use of a reference Material Proposed by the International federation of Clinical Chemistry and Laboratory Medicine to Evaluate Analytical methods for the Determination of Plasma Lipoprotein (a). Clin Chem 2000 Dec;46(12):1956-1967.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. These data represent the performance of the analytical procedure itself.

Results obtained in individual laboratories may differ due to heterogenous sample materials, aging of analyzer components and mixture of reagents running on the analyzer.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Precision was determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP05‑A3 requirements with repeatability (n = 84) and intermediate precision (2 aliquots per run, 2 runs per day, 21 days). The following results were obtained:

Repeatability

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control Level Low

35.2

0.412

1.2

Lp (a) Control Level High

97.7

0.435

0.4

Human serum 1

19.7

0.414

2.1

Human serum 2

49.3

0.516

1.0

Human serum 3

80.5

0.434

0.5

Human serum 4

120

0.546

0.5

Human serum 5

203

0.794

0.4

Intermediate precision

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control Level Low

35.1

0.562

1.6

Lp (a) Control Level High

99.0

1.14

1.2

Human serum 1

19.7

0.508

2.6

Human serum 2

49.3

0.676

1.4

Human serum 3

80.5

0.831

1.0

Human serum 4

119

1.14

1.0

Human serum 5

203

1.33

0.7

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 503 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer  (x).

Sample size (n) = 99

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.019x + 0.878 nmol/L

y = 1.010x + 1.34 nmol/L

τ = 0.988

r = 1.000

The sample concentrations were between 7.34 and 235 nmol/L.

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.

Main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.

LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.

The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa. Assays with antibodies directed against this variable part of the Lp(a) molecule will underestimate Lp(a) in patients with apo (a) smaller than in the used calibrator and overestimate Lp(a) in such samples with larger apo (a) particles as in the calibrator. Based on the size heterogeneity it makes no sense to measure Lp(a) mass. Therefore the values should be expressed in terms of nanomoles per liter of Lp(a) protein.

Only standardization of these assays against an apo (a) size independent method will yield correct results. Such methods use antibodies that recognize a single copy of apo (a) per particle. By using the WHO/IFCC International Reference Reagent (SRM2B) this goal can be reached.

LREFDati F, Tate JR, Marcovina SM, et al. First WHO/IFCC International reference Reagent for Lipoprotein(a) for immunoassay - Lp(a) SRM2B. Clin Chem Lab Med 2004;42(6):670-676.
The value in this material has been assigned by using two different ELISA's based on monoclonal antibodies specific to two different unique epitopes present in apo (a).
LREFMarcovina SM, Albers JJ, Gabel B, et al. Effect of the Number of Apolipoprotein (a) Kringle 4 Domains on Immunochemical Measurements of Lipoprotein(a). Clin Chem 1995 Feb;41(2):246-255.
,
LREFMarcovina SM, Albers JJ, Wijsman E, et al. Differences in Lp(a) Concentrations and Apo(a) Polymorphs Between Black and White Americans. J Lipid Res 1996 Dec;37(12):2569-2585.
High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. When lipoprotein (a) concentrations exceed 75 nmol/L, the coronary risk is approximately doubled. In combination with elevated LDL‑cholesterol concentrations, the risk increases approximately 6‑fold. An elevated lipoprotein (a) level is considered to be the most sensitive parameter for the development of coronary heart disease, irrespective of other plasma lipoproteins. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk.

According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.

LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; stabilizers; BSA; rabbit serum 0.1 %, preservative

R3

Latex particles coated with polyclonal anti‑human lipoprotein(a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3, BSA; preservative

R1 is in position B and R3 is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use for health care professionals. Exercise the normal precautions required for handling all laboratory reagents.

Infectious or microbial waste:
Warning: handle waste as potentially biohazardous material. Dispose of waste according to accepted laboratory instructions and procedures.

Environmental hazards:
Apply all relevant local disposal regulations to determine the safe disposal.

Safety data sheet available for professional user on request.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

For quality control, use control materials as listed in the “Order information” section. In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. It is recommended to perform quality control always after lot calibration and subsequently at least every 26 weeks. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li‑heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

See the limitations and interferences section for details about possible sample interferences.

Stability:

If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.

If samples are not assayed within 48 h,

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at −70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

", "Language": "en" } ] } }, { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0208106126190c503", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "2", "DocumentObjectID": "FF00000004CEA00E", "DocumentOriginID": "FF00000003FA730E", "MaterialNumbers": [ "08106126190" ], "InstrumentReferences": [ { "ID": "9493", "BrandName": "cobas c 303" }, { "ID": "8481", "BrandName": "cobas c 503" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on Roche/Hitachi cobas c systems. The measurement of Lp(a) is useful in evaluating lipid metabolism disorders and assessing atherosclerotic cardiovascular disease in specific populations, when used in conjunction with clinical evaluation and other lipoprotein tests.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle enhanced immunoturbidimetric assay.

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.

Human lipoprotein (a) agglutinates with latex particles coated with anti‑Lp(a) antibodies. The precipitate is determined turbidimetrically at 800 / 660 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

Measuring range: 6.0‑80 mg/dL

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank

= 3 mg/dL

Limit of Detection

= 4 mg/dL

Limit of Quantitation

= 6 mg/dL

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 30 %. It has been determined using low concentration lipoprotein (a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

The defined threshold of Lp(a) concentration at which individuals can be classified as being at increased risk varies greatly among studies, ranging from 20 mg/dL to 40 mg/dL. A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The Europen Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

Different Lp(a) levels can be found in different racial/ethnicity groups.

LREFWu HD, Berglund L, Dimayuga C, et al. High Lipoprotein (a) Levels and Small Apolipoprotein (a) Sizes are Associated With Endothelial Dysfunction in a Multiethnic Cohort. J Am Coll Cardiol 2004 May;43(10):1828-1833.
,
LREFVirani SS, Brautbar A, Davis BC, et al. Associations Between Lipoprotein (a) Levels and Cardiovascular Outcomes in Black and White Subjects. The Atherosclerosis Risk in Communities (ARIC) Study. Circulation 2012;125(2):241-249.
Since Lp(a) levels are largely influenced by hereditary factors, they vary with ethnic populations. Therefore, reference ranges have not been established for this assay for different ethnic populations or disease states.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations – interference

Criterion: Recovery within ± 3 mg/dL of initial values of samples ≤ 30 mg/dL and within ± 10 % for samples > 30 mg/dL.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference from rheumatoid factors up to a concentration of 1200 IU/mL.

Plasminogen: No significant cross‑reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross‑reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 190 mg/dL.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on cobas c systems. All special wash programming necessary for avoiding carry-over is available via the cobas link. The latest version of the carry-over evasion list can be found with the NaOHD/SMS/SCCS Method Sheet. For further instructions, refer to the operator’s manual.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

OrderInformation (CC Reagents - cobas + Integra)

Analyzer(s) on which cobas c pack(s) can be used

08106126190

Tina‑quant Lipoprotein (a) Gen.2 (150 tests)

System‑ID 2086 001

cobas c 303,cobas c 503

05852641160

Preciset Lp(a) Gen.2 (5 × 1 mL)

Codes 20962‑20966

05852650160

PreciControl Lp(a) Gen.2
Level Low (2 × 1 mL)
Level High (2 × 1 mL)


Code 20137
Code 20138

08063494190

Diluent NaCl 9 % (123 mL)

System‑ID 2906 001

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

LPA2X: ACN 20861

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum and plasma

Test definition

Reporting time

10 min

Wavelength (sub/main)

800/660 nm

Reagent pipetting

Diluent (H2O)

R1

100 µL

R3

25 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

1.5 µL

Decreased

6.0 µL

8 µL

88 µL

Increased

1.5 µL

For further information about the assay test definitions refer to the application parameters screen of the corresponding analyzer and assay.

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

26 weeks

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrators

S1: H2O
S2‑S6: Preciset Lp(a) Gen.2

Calibration mode

Non-linear

Calibration frequency

Automatic full calibration
- after reagent lot change

Full calibration
- as required following quality control procedures

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against an in-house reference material.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. These data represent the performance of the analytical procedure itself.

Results obtained in individual laboratories may differ due to heterogenous sample materials, aging of analyzer components and mixture of reagents running on the analyzer.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Precision was determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP05‑A3 requirements with repeatability (n = 84) and intermediate precision (2 aliquots per run, 2 runs per day, 21 days). Results for repeatability and intermediate precision were obtained on the cobas c 503 analyzer.

Repeatability

Mean
mg/dL

SD
mg/dL

CV
%

Lp (a) Control Level Low

19.5

0.158

0.8

Lp (a) Control Level High

47.2

0.197

0.4

Human serum 1

13.8

0.250

1.8

Human serum 2

38.1

0.170

0.4

Human serum 3

53.7

0.174

0.3

Human serum 4

65.6

0.216

0.3

Human serum 5

79.3

0.321

0.4

Intermediate precision

Mean
mg/dL

SD
mg/dL

CV
%

Lp (a) Control Level Low

19.5

0.219

1.1

Lp (a) Control Level High

47.2

0.490

1.0

Human serum 1

13.8

0.286

2.1

Human serum 2

38.1

0.262

0.7

Human serum 3

53.7

0.355

0.7

Human serum 4

65.6

0.601

0.9

Human serum 5

79.3

0.620

0.8

The data obtained on cobas c 503 analyzer(s) are representative for cobas c 303 analyzer(s).

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 503 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer (x).

Sample size (n) = 83

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.020x + 0.343 mg/dL

y = 1.013x + 0.537 mg/dL

τ = 0.981

r = 0.999

The sample concentrations were between 6.57 and 77.6 mg/dL.

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 303 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer (x).

Sample size (n) = 64

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.000x + 0.385 mg/dL

y = 0.990x + 0.788 mg/dL

τ = 0.984

r = 0.999

The sample concentrations were between 6.21 and 74.9 mg/dL.

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.

The main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.

LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.

The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa.

High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk.

According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.

LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; stabilizers; BSA; rabbit serum 0.1 %, preservative

R3

Latex particles coated with polyclonal anti‑human lipoprotein (a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3, BSA; preservative

R1 is in position B and R3 is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use.
Exercise the normal precautions required for handling all laboratory reagents.
Disposal of all waste material should be in accordance with local guidelines.
Safety data sheet available for professional user on request.

For USA: Caution: Federal law restricts this device to sale by or on the order of a physician.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

For quality control, use control materials as listed in the \"Order information\" section.

In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. It is recommended to perform quality control always after lot calibration and subsequently at least every 26 weeks. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li‑heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

Plasma samples drawn with each of Li‑Heparin, K2‑, K3‑EDTA, serum and additionally gel separation tubes from 39 subjects were evaluated on a cobas c 501 system using the Roche Lp(a) Gen. 2 reagent and calibrators. Results of the comparison study showed that serum and plasma samples can provide substantially the same Lp(a) values.

Serum

Li-
Heparin

K2-
EDTA

K3-
EDTA

Gel separation tubes

Median [mg/dL]
Mean [mg/dL]
Min. [mg/dL]
Max. [mg/dL]
SD [mg/dL]

27.2
31.8
6.60
77.4
21.6

27.5
30.9
6.60
76.0
21.1

27.2
31.3
6.50
76.7
21.2

27.0
30.2
6.40
73.1
20.4

27.5
31.7
6.40
76.8
21.5

Serum vs. plasma
Slope (P/B)
Intercept (P/B)
Correlation (Pearson)


-
-
-


0.979
‑0.066
0.999


0.974
0.249
0.999


0.944
0.106
1.000


0.997
0.0393
1.000

LCL 95 (Intercept)
UCL 95 (Intercept)
LCL 95 (Slope)
UCL 95 (Slope)

-
-
-
-

‑0.392
0.274
0.968
0.987

‑0.068
0.480
0.963
0.989

‑0.127
0.312
0.934
0.953

‑0.151
0.199
0.988
1.01

See the limitations and interferences section for details about possible sample interferences.

Stability:

If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.

If samples are not assayed within 48 h,

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at −70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

Sample stability claims were established by experimental data by the manufacturer or based on reference literature and only for the temperatures/time frames as stated in the method sheet. It is the responsibility of the individual laboratory to use all available references and/or its own studies to determine specific stability criteria for its laboratory.

", "Language": "en" } ] } }, { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0108106126190c503", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "4", "DocumentObjectID": "FF000000051EF60E", "DocumentOriginID": "FF000000051EF60E", "MaterialNumbers": [ "08106126190" ], "InstrumentReferences": [ { "ID": "9493", "BrandName": "cobas c 303" }, { "ID": "8481", "BrandName": "cobas c 503" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on Roche/Hitachi cobas c systems.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle enhanced immunoturbidimetric assay.

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.

Human lipoprotein (a) agglutinates with latex particles coated with anti‑Lp(a) antibodies. The precipitate is determined turbidimetrically at 800 / 660 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

Measuring range: 7‑240 nmol/L

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank

= 6 nmol/L

Limit of Detection

= 7 nmol/L

Limit of Quantitation

= 20 nmol/L

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 20 %. It has been determined using low concentration lipoprotein (a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The European Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

However the NHLBI recommends to stop using data for total Lp(a) mass, and to use nmol/L units instead, which consider the number of particles. Additionally they recommend to use assays independent from apo(a) size and standardized according to the IFCC reference material SRM2B.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Based on the evaluation of Framingham data values above 75 nmol/L are regarded as a cut‑off value for the presence of an increased risk.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Elevated Lp(a) levels can be found in most racial/ethnicity groups, with the prevalence being lowest in whites and Asians. The median Lp(a) levels in black subjects and in Asian Indians from southern locations are 2‑ to 4‑fold higher compared with whites, and up to 68 % of blacks have Lp(a) levels > 75 nmol/L, whereas levels above this threshold are present in around 25 % of whites.

LREFTsimikas S, Clopton P, Brilakis ES, et al. Relationship of Oxidized Phospholipids on Apolipoprotein B-100 Particles to Race/Ethnicity, Apolipoprotein (a) Isoform Size, and Cardiovascular Risk Factors: Results From the Dallas Heart Study, Circulation 2009 Apr;119(13):1711-1719.

Therefore reference ranges have not been established for this assay for different ethnic populations or disease states. Since Lp(a) levels are largely influenced by hereditary factors and vary with ethnic populations it is recommended that each laboratory establish own expected values.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations – interference

Criterion: Recovery within ± 6 nmol/L of initial values of samples ≤ 60 nmol/L and within ± 10 % for samples > 60 nmol/L.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference from rheumatoid factors up to a concentration of 1200 IU/mL.

Plasminogen: No significant cross‑reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross‑reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 450 nmol/L.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on cobas c systems. All special wash programming necessary for avoiding carry-over is available via the cobas link. The latest version of the carry-over evasion list can be found with the NaOHD/SMS/SCCS Method Sheet for information. For further instructions refer to the operator’s manual.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

OrderInformation (CC Reagents - cobas + Integra)

Analyzer(s) on which cobas c pack(s) can be used

08106126190

Tina‑quant Lipoprotein (a) Gen.2 (150 tests)

System‑ID 2086 001

cobas c 303, cobas c 503

Materials required (but not provided):

05852641190

Preciset Lp(a) Gen.2 (5 × 1 mL)

Codes 20962‑20966

05852650190

PreciControl Lp(a) Gen.2
Level Low (2 × 1 mL)
Level High (2 × 1 mL)


Code 20137
Code 20138

08063494190

Diluent NaCl 9 % (123 mL)

System‑ID 2906 001

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

LPA2: ACN 20860

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum and plasma

Test definition

Reporting time

10 min

Wavelength (sub/main)

800/660 nm

Reagent pipetting

Diluent (H2O)

R1

100 µL

R3

25 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

1.5 µL

Decreased

6.0 µL

8 µL

88 µL

Increased

1.5 µL

For further information about the assay test definitions refer to the application parameters screen of the corresponding analyzer and assay.

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

26 weeks

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrators

S1: H2O
S2‑S6: Preciset Lp(a) Gen.2

Calibration mode

Non-linear

Calibration frequency

Automatic full calibration
- after reagent lot change

Full calibration
- as required following quality control procedures

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against the IFCC reference material SRM2B for nmol/L.

LREFMarcovina SM, Albers JJ, Scanu AM, et al. Use of a reference Material Proposed by the International federation of Clinical Chemistry and Laboratory Medicine to Evaluate Analytical methods for the Determination of Plasma Lipoprotein (a). Clin Chem 2000 Dec;46(12):1956-1967.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. These data represent the performance of the analytical procedure itself.

Results obtained in individual laboratories may differ due to heterogenous sample materials, aging of analyzer components and mixture of reagents running on the analyzer.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Precision was determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP05‑A3 requirements with repeatability (n = 84) and intermediate precision (2 aliquots per run, 2 runs per day, 21 days). Results for repeatability and intermediate precision were obtained on the cobas c 503 analyzer.

Repeatability

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control Level Low

35.2

0.412

1.2

Lp (a) Control Level High

97.7

0.435

0.4

Human serum 1

19.7

0.414

2.1

Human serum 2

49.3

0.516

1.0

Human serum 3

80.5

0.434

0.5

Human serum 4

120

0.546

0.5

Human serum 5

203

0.794

0.4

Intermediate precision

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control Level Low

35.1

0.562

1.6

Lp (a) Control Level High

99.0

1.14

1.2

Human serum 1

19.7

0.508

2.6

Human serum 2

49.3

0.676

1.4

Human serum 3

80.5

0.831

1.0

Human serum 4

119

1.14

1.0

Human serum 5

203

1.33

0.7

The data obtained on cobas c 503 analyzer(s) are representative for cobas c 303 analyzer(s).

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 503 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer  (x).

Sample size (n) = 99

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.019x + 0.878 nmol/L

y = 1.010x + 1.34 nmol/L

τ = 0.988

r = 1.000

The sample concentrations were between 7.34 and 235 nmol/L.

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 303 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer  (x).

Sample size (n) = 72

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 0.984x + 2.00 nmol/L

y = 0.988x + 1.70 nmol/L

τ = 0.990

r = 1.000

The sample concentrations were between 7.07 and 222 nmol/L.

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.

Main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.

LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.

The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa. Assays with antibodies directed against this variable part of the Lp(a) molecule will underestimate Lp(a) in patients with apo (a) smaller than in the used calibrator and overestimate Lp(a) in such samples with larger apo (a) particles as in the calibrator. Based on the size heterogeneity it makes no sense to measure Lp(a) mass. Therefore the values should be expressed in terms of nanomoles per liter of Lp(a) protein.

Only standardization of these assays against an apo (a) size independent method will yield correct results. Such methods use antibodies that recognize a single copy of apo (a) per particle. By using the WHO/IFCC International Reference Reagent (SRM2B) this goal can be reached.

LREFDati F, Tate JR, Marcovina SM, et al. First WHO/IFCC International reference Reagent for Lipoprotein(a) for immunoassay - Lp(a) SRM2B. Clin Chem Lab Med 2004;42(6):670-676.
The value in this material has been assigned by using two different ELISA's based on monoclonal antibodies specific to two different unique epitopes present in apo (a).
LREFMarcovina SM, Albers JJ, Gabel B, et al. Effect of the Number of Apolipoprotein (a) Kringle 4 Domains on Immunochemical Measurements of Lipoprotein(a). Clin Chem 1995 Feb;41(2):246-255.
,
LREFMarcovina SM, Albers JJ, Wijsman E, et al. Differences in Lp(a) Concentrations and Apo(a) Polymorphs Between Black and White Americans. J Lipid Res 1996 Dec;37(12):2569-2585.
High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. When lipoprotein (a) concentrations exceed 75 nmol/L, the coronary risk is approximately doubled. In combination with elevated LDL‑cholesterol concentrations, the risk increases approximately 6‑fold. An elevated lipoprotein (a) level is considered to be the most sensitive parameter for the development of coronary heart disease, irrespective of other plasma lipoproteins. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk.

According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.

LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; stabilizers; BSA; rabbit serum 0.1 %, preservative

R3

Latex particles coated with polyclonal anti‑human lipoprotein(a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3, BSA; preservative

R1 is in position B and R3 is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use for health care professionals. Exercise the normal precautions required for handling all laboratory reagents.

Infectious or microbial waste:
Warning: handle waste as potentially biohazardous material. Dispose of waste according to accepted laboratory instructions and procedures.

Environmental hazards:
Apply all relevant local disposal regulations to determine the safe disposal.

Safety data sheet available for professional user on request.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

For quality control, use control materials as listed in the “Order information” section. In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. It is recommended to perform quality control always after lot calibration and subsequently at least every 26 weeks. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li‑heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

See the limitations and interferences section for details about possible sample interferences.

Stability:

If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.

If samples are not assayed within 48 h,

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at −70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

", "Language": "en" } ] } }, { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0105852633190c701", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "5", "DocumentObjectID": "FF0000000478210E", "DocumentOriginID": "FF0000000004AD0E", "MaterialNumbers": [ "05852633190" ], "InstrumentReferences": [ { "ID": "2492", "BrandName": "cobas c 702" }, { "ID": "310", "BrandName": "cobas c 701" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on Roche/Hitachi cobas c systems.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle enhanced immunoturbidimetric assay.

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.
Human lipoprotein (a) agglutinates with latex particles coated with anti‑Lp(a) antibodies. The precipitate is determined turbidimetrically at 800 / 660 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

Measuring range: 7‑240 nmol/L

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank

= 6 nmol/L

Limit of Detection

= 7 nmol/L

Limit of Quantitation

= 20 nmol/L

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 30 %. It has been determined using low concentration Lp(a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The European Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

However the NHLBI recommends to stop using data for total Lp(a) mass, and to use nmol/L units instead, which consider the number of particles. Additionally they recommend to use assays independent from apo(a) size and standardized according to the IFCC reference material SRM2B.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Based on the evaluation of Framingham data values above 75 nmol/L are regarded as a cut‑off value for the presence of an increased risk.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Elevated Lp(a) levels can be found in most racial/ethnicity groups, with the prevalence being lowest in whites and Asians. The median Lp(a) levels in black subjects and in Asian Indians from southern locations are 2‑ to 4‑fold higher compared with whites, and up to 68 % of blacks have Lp(a) levels > 75 nmol/L, whereas levels above this threshold are present in around 25 % of whites.

LREFTsimikas S, Clopton P, Brilakis ES, et al. Relationship of Oxidized Phospholipids on Apolipoprotein B-100 Particles to Race/Ethnicity, Apolipoprotein (a) Isoform Size, and Cardiovascular Risk Factors: Results From the Dallas Heart Study, Circulation 2009 Apr;119(13):1711-1719.

Therefore reference ranges have not been established for this assay for different ethnic populations or disease states. Since Lp(a) levels are largely influenced by hereditary factors and vary with ethnic populations it is recommended that each laboratory establish own expected values.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations – interference

Criterion: Recovery within ± 6 nmol/L of initial values of samples ≤ 60 nmol/L and within ± 10 % for samples > 60 nmol/L.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference up to a level of 1200 IU/mL.

Plasminogen: No significant cross‑reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross‑reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 450 nmol/L.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on cobas c systems. All special wash programming necessary for avoiding carry‑over is available via the cobas link, manual input is required in certain cases. The latest version of the carry‑over evasion list can be found with the NaOHD/SMS/SmpCln1+2/SCCS Method Sheet and for further instructions refer to the operator’s manual.

Where required, special wash/carry‑over evasion programming must be implemented prior to reporting results with this test.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

OrderInformation (CC Reagents - cobas + Integra)

Analyzer(s) on which cobas c pack(s) can be used

05852633 190

Tina-quant Lipoprotein (a) Gen.2 (200 tests)

System‑ID 03 7504 5

cobas c 701/702

Materials required (but not provided):

05852641 190

Preciset Lp(a) Gen.2 ( 5 x 1 mL)

Codes 962-966

05852650 190

PreciControl Lp(a) Gen.2 (Level Low 2 x 1 mL)
PreciControl Lp(a) Gen.2 (Level High 2 x 1 mL)

Code 137
Code 138

05172152 190

Diluent NaCL 9 % (119 mL)

System‑ID 08 6869 3

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

LPA2: ACN 8723.

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum and plasma

cobas c 701/702 test definition

Assay type

2‑Point End

Reaction time / Assay points

10 / 22‑33

Wavelength (sub/main)

800 / 660 nm

Reaction direction

Increase

Unit

nmol/L

Reagent pipetting

Diluent (H2O)

R1

133 µL

R3

33 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

2.0 µL

0 µL

0 µL

Decreased

8.0 µL

10 µL

110 µL

Increased

4.0 µL

0 µL

0 µL

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

LPA2

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

6 weeks

On‑board on the Reagent Manager:

24 hours

Diluent NaCl 9  %

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

4 weeks

On‑board on the Reagent Manager:

24 hours

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrators

S1: H2O
S2‑S6: Preciset Lp(a) Gen.2

Calibration mode

Spline

Calibration frequency

Full calibration
‑ after reagent lot change
‑ as required following quality control procedures

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against the IFCC reference material SRM2B for nmol/L.

LREFMarcovina SM, Albers JJ, Scanu AM, et al. Use of a reference Material Proposed by the International federation of Clinical Chemistry and Laboratory Medicine to Evaluate Analytical methods for the Determination of Plasma Lipoprotein (a). Clin Chem 2000 Dec;46(12):1956-1967.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Repeatability was determined using human samples and controls in an internal protocol (n = 21, 1 run). Intermediate precision was determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP5 requirements (2 aliquots per run, 2 runs per day, 21 days). The following results were obtained:

Repeatability

Sample

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control level L

41.7

0.5

1.2

Lp (a) Control level H

167

1

0.7

Human serum 4

24.6

0.4

1.7

Human serum 5

66.4

1.6

2.4

Human serum 7

233

1

0.6

Intermediate precision

Sample

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control level L

40.7

0.7

1.7

Lp (a) Control level H

156

2

1.2

Human serum 1

18.2

1.5

8.0

Human serum 2

88.7

2.7

3.0

Human serum 3

226

2

1.1

Results for intermediate precision were obtained on the master system cobas c 501 analyzer.

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 701 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer (x).

Sample size (n) = 163

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.00x + 0.000 nmol/L

y = 0.998x - 0.098 nmol/L

τ = 0.977

r = 1.00

The sample concentrations were between 7.10 and 233 nmol/L.

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.

Main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.

LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.

The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa. Assays with antibodies directed against this variable part of the Lp(a) molecule will underestimate Lp(a) in patients with apo (a) smaller than in the used calibrator and overestimate Lp(a) in such samples with larger apo (a) particles as in the calibrator. Based on the size heterogeneity it makes no sense to measure Lp(a) mass. Therefore the values should be expressed in terms of nanomoles per liter of Lp(a) protein.

Only standardization of these assays against an apo (a) size independent method will yield correct results. Such methods use antibodies that recognize a single copy of apo (a) per particle. By using the WHO/IFCC International Reference Reagent (SRM2B) this goal can be reached.

LREFDati F, Tate JR, Marcovina SM, et al. First WHO/IFCC International reference Reagent for Lipoprotein(a) for immunoassay - Lp(a) SRM2B. Clin Chem Lab Med 2004;42(6):670-676.
The value in this material has been assigned by using two different ELISA's based on monoclonal antibodies specific to two different unique epitopes present in apo (a).
LREFMarcovina SM, Albers JJ, Gabel B, et al. Effect of the Number of Apolipoprotein (a) Kringle 4 Domains on Immunochemical Measurements of Lipoprotein(a). Clin Chem 1995 Feb;41(2):246-255.
,
LREFMarcovina SM, Albers JJ, Wijsman E, et al. Differences in Lp(a) Concentrations and Apo(a) Polymorphs Between Black and White Americans. J Lipid Res 1996 Dec;37(12):2569-2585.
High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. When lipoprotein (a) concentrations exceed 75 nmol/L, the coronary risk is approximately doubled. In combination with elevated LDL‑cholesterol concentrations, the risk increases approximately 6‑fold. An elevated lipoprotein (a) level is considered to be the most sensitive parameter for the development of coronary heart disease, irrespective of other plasma lipoproteins. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk.

According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.

LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; stabilizers; BSA; rabbit serum 0.1 %, preservative

R3

Latex particles coated with polyclonal anti‑human lipoprotein(a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3, BSA; preservative

R1 is in position B and R3 is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use for health care professionals. Exercise the normal precautions required for handling all laboratory reagents.

Infectious or microbial waste:
Warning: handle waste as potentially biohazardous material. Dispose of waste according to accepted laboratory instructions and procedures.

Environmental hazards:
Apply all relevant local disposal regulations to determine the safe disposal.

Safety data sheet available for professional user on request.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

For quality control, use control materials as listed in the \"Order information\" section.

In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li‑heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

See the limitations and interferences section for details about possible sample interferences.

Stability:

If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.

If samples are not assayed within 48 h,

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at -70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

", "Language": "en" } ] } }, { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0105852625190COIN", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "6", "DocumentObjectID": "FF00000004894F0E", "DocumentOriginID": "FF000000000E420E", "MaterialNumbers": [ "05852625190" ], "InstrumentReferences": [ { "ID": "302", "BrandName": "COBAS INTEGRA 400 plus" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on COBAS INTEGRA systems.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle-enhanced immunoturbidimetric assay

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.

Human lipoprotein (a) agglutinates with latex particles coated with anti-Lp(a) antibodies. The precipitate is determined turbidimetrically at 659 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

7-240 nmol/L

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank, Limit of Detection and Limit of Quantitation

Limit of Blank

= 6 nmol/L

Limit of Detection

= 7 nmol/L

Limit of Quantitation

= 20 nmol/L

The Limit of Blank, the Limit of Detection and the Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 30 %. It has been determined using low concentration Lp(a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The European Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

However the NHLBI recommends to stop using data for total Lp(a) mass, and to use nmol/L units instead, which consider the number of particles. Additionally they recommend to use assays independent from apo(a) size and standardized according to the IFCC reference material SRM2B.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Based on the evaluation of Framingham data values above 75 nmol/L are regarded as a cut-off value for the presence of an increased risk.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.
Elevated Lp(a) levels can be found in most racial/ethnicity groups, with the prevalence being lowest in whites and Asians. The median Lp(a) levels in black subjects and in Asian Indians from southern locations are 2‑ to 4‑fold higher compared with whites, and up to 68 % of blacks have Lp(a) levels > 75 nmol/L, whereas levels above this threshold are present in around 25 % of whites.
LREFTsimikas S, Clopton P, Brilakis ES, et al. Relationship of Oxidized Phospholipids on Apolipoprotein B-100 Particles to Race/Ethnicity, Apolipoprotein (a) Isoform Size, and Cardiovascular Risk Factors: Results From the Dallas Heart Study, Circulation 2009 Apr;119(13):1711-1719.
Therefore reference ranges have not been established for this assay for different ethnic populations or disease states. Since Lp(a) levels are largely influenced by hereditary factors and vary with ethnic populations it is recommended that each laboratory establish own expected values.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations - interference

Criterion: Recovery within ± 6 nmol/L of initial values of samples ≤ 60 nmol/L and within ± 10 % for samples > 60 nmol/L.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL ).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference up to a rheumatoid factors level of 1200 IU/mL.

Plasminogen: No significant cross reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 450 nmol/L.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on COBAS INTEGRA analyzers. Refer to the CLEAN Method Sheet for further instructions and for the latest version of the Extra wash cycle list.
Where required, special wash/carry-over evasion programming must be implemented prior to reporting results with this test.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

Order Information

Order information

Analyzers on which cobas c pack(s) can be used

05852625 190

Tina-quant Lipoprotein (a) Gen.2 (150 tests)

System-ID 07 7504 5

COBAS INTEGRA 400 plus

Materials required (but not provided):

05852641 190

Preciset Lp(a) Gen.2 (5 × 1 mL)

System-ID 07 7546 0

05852650 190

PreciControl Lp(a) Gen.2
   Level Low (2 × 1 mL)
   Level High (2 × 1 mL)


System-ID 07 7544 4
System-ID 07 7545 2

20756350 322

NaCl Diluent 9 % (6 × 22 mL)

System-ID 07 5635 0

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

Test LPA2, test ID 0‑039

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum/plasma

Test definition

Measuring mode

Absorbance

Abs. calculation mode

Endpoint

Reaction mode

D-R1-S-SR

Reaction direction

Increase

Wavelength A/B

659 nm

Calc. first/last

36-53

Typical prozone effect

> 450 nmol/L

Antigen excess check

No

Predilution factor

11

Unit

nmol/L

Pipetting parameters

Diluent (H2O)

R1

133 µL

SR

33 µL

5 µL

Sample

20 µL

Total volume

191 µL

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

Shelf life at 2‑8 °C

See expiration date on cobas c pack label

On‑board in use at 10‑15 °C

6 weeks

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrator

Preciset Lp(a) Gen. 2

Use deionized water as zero calibrator.

Calibration mode

Spline

Calibration replicate

Duplicate recommended

Calibration interval

Each lot and as required following quality control procedures

Calibrators must be placed from the highest concentration first, to the lowest last, on the CAL/QC rack. 0 nmol/L calibrator is not provided with Preciset Lp(a) Gen.2. Please use deionized water as zero calibrator.

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against the IFCC reference material SRM2B for nmol/L.

LREFMarcovina SM, Albers JJ, Scanu AM, et al. Use of a reference Material Proposed by the International federation of Clinical Chemistry and Laboratory Medicine to Evaluate Analytical methods for the Determination of Plasma Lipoprotein (a). Clin Chem 2000 Dec;46(12):1956-1967.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Repeatability and intermediate precision were determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP5 requirements (2 aliquots per run, 2 runs per day, 21 days). The following results were obtained:

Repeatability

Mean
nmol/L

SD
nmol/L

CV
%

PreciControl Level L

37.0

0.5

1.3

PreciControl Level H

136

1

0.6

Human serum 1

16.7

0.6

3.7

Human serum 3

86.3

0.5

0.6

Human serum 5

205

1

0.4

Intermediate precision

Mean
nmol/L

SD
nmol/L

CV
%

PreciControl Level L

37.0

0.5

1.4

PreciControl Level H

136

1

0.7

Human serum 1

16.7

0.6

3.8

Human serum 3

86.3

1.0

1.1

Human serum 5

205

1

0.6

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a COBAS INTEGRA 800 analyzer (y) were compared with those determined using the corresponding reagent on a cobas c 501 analyzer (x).

Sample size (n) = 240

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.02x + 0.290 nmol/L

y = 1.01x + 0.972 nmol/L

τ = 0.938

r = 0.999

The sample concentrations were between 7.11 and 234 nmol/L.

Lipoprotein (a) values for human serum and plasma samples obtained on a COBAS INTEGRA 800 analyzer (y) were compared with those determined using the Northwest Lipid Metabolism and Diabetes Research Laboratories ELISA method traceable to the WHO/IFCC reference material SRM2B (x).

Sample size (n) = 105

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 1.01x + 1.92 nmol/L

y  = 0.975x + 3.13 nmol/L

τ = 0.939

r = 0.993

The sample concentrations were between 7.10 and 218 nmol/L.

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) (Lp(a)) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.
Main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.
LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.
The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa.

Assays with antibodies directed against this variable part of the Lp(a) molecule will underestimate Lp(a) in patients with apo (a) smaller than in the used calibrator and overestimate Lp(a) in such samples with larger apo (a) particles as in the calibrator. Based on the size heterogeneity it makes no sense to measure Lp(a) mass. Therefore the values should be expressed in terms of nanomoles per liter of Lp(a) protein.

Only standardization of these assays against an apo (a) size independent method will yield correct results. Such methods use antibodies that recognize a single copy of apo (a) per particle. By using the WHO/IFCC International Reference Reagent (SRM2B) this goal can be reached.

LREFDati F, Tate JR, Marcovina SM, et al. First WHO/IFCC International reference Reagent for Lipoprotein(a) for immunoassay - Lp(a) SRM2B. Clin Chem Lab Med 2004;42(6):670-676.
The value in this material has been assigned by using two different ELISA’s based on monoclonal antibodies specific to two different unique epitopes present in apo (a).
LREFMarcovina SM, Albers JJ, Gabel B, et al. Effect of the Number of Apolipoprotein (a) Kringle 4 Domains on Immunochemical Measurements of Lipoprotein(a). Clin Chem 1995 Feb;41(2):246-255.
,
LREFMarcovina SM, Albers JJ, Wijsman E, et al. Differences in Lp(a) Concentrations and Apo(a) Polymorphs Between Black and White Americans. J Lipid Res 1996 Dec;37(12):2569-2585.
High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. When lipoprotein (a) concentrations exceed 75 nmol/L, the coronary risk is approximately doubled. In combination with elevated LDL‑cholesterol concentrations, the risk increases approximately 6‑fold. An elevated lipoprotein (a) level is considered to be the most sensitive parameter for the development of coronary heart disease, irrespective of other plasma lipoproteins. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk. According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.
LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; BSA; rabbit serum 0.1 %; stabilizers; preservative

SR

Latex particles coated with polyclonal anti‑human lipoprotein (a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3; BSA; preservative

R1 is in position B and SR is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use for health care professionals. Exercise the normal precautions required for handling all laboratory reagents.

Infectious or microbial waste:
Warning: handle waste as potentially biohazardous material. Dispose of waste according to accepted laboratory instructions and procedures.

Environmental hazards:
Apply all relevant local disposal regulations to determine the safe disposal.

Safety data sheet available for professional user on request.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

Quality control

PreciControl Lp(a) Gen. 2

Control interval

24 hours recommended

Control sequence

User defined

Control after calibration

Recommended

For quality control, use control materials as listed in the “Order information” section. In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li-heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

See the limitations and interferences section for details about possible sample interferences.

Samples and controls are automatically prediluted 1:11 (1 + 10) with NaCl solution by the instrument.

Stability:
If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
If samples are not assayed within 48 h,
LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at -70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

", "Language": "en" } ] } }, { "ProductSpecVariant": { "MetaData": { "DocumentMaterialNumber": "0105852625190c501", "ProductName": "LPA2", "ProductLongName": "Tina-quant Lipoprotein (a) Gen.2", "Language": "en", "DocumentVersion": "5", "DocumentObjectID": "FF00000004894E0E", "DocumentOriginID": "FF000000000B160E", "MaterialNumbers": [ "05852625190" ], "InstrumentReferences": [ { "ID": "308", "BrandName": "cobas c 311" }, { "ID": "2324", "BrandName": "cobas c 502" }, { "ID": "309", "BrandName": "cobas c 501" } ], "DisclaimerText": "Product information shown on this page contains elements of the officially released Method Sheet. If you require further information please refer to the full Method Sheet PDF under the given link, or contact your local Roche country representative." }, "Chapters": [ { "Name": "IntendedUse", "Value": "

Intended use

In vitro test for the quantitative determination of lipoprotein (a) in human serum and plasma on Roche/Hitachi cobas c systems.

", "Language": "en" }, { "Name": "TestPrinciple", "Value": "

Test principle

Particle enhanced immunoturbidimetric assay.

LREFSimó JM, Camps J, Gómez F, et al. Evaluation of a Fully Automated Particle-enhanced Turbidimetric Immunoassay for the Meaurement of Plasma Lipoprotein(a). Population-Based Reference Values in an Area with Low Incidence of Cardiovascular Disease. Clin Biochem 2003 Mar;36(2):129-134.
Human lipoprotein (a) agglutinates with latex particles coated with anti‑Lp(a) antibodies. The precipitate is determined turbidimetrically at 800 / 660 nm.

", "Language": "en" }, { "Name": "MeasuringRange", "Value": "

Limits and ranges

Measuring range

Measuring range: 7‑240 nmol/L

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:3 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 3.

Lower limits of measurement

Limit of Blank

= 6 nmol/L

Limit of Detection

= 7 nmol/L

Limit of Quantitation

= 20 nmol/L

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17‑A2 requirements.

The Limit of Blank is the 95th percentile value from n ≥ 60 measurements of analyte‑free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte‑free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

The Limit of Quantitation is the lowest analyte concentration that can be reproducibly measured with a total error of 30 %. It has been determined using low concentration Lp(a) samples.

", "Language": "en" }, { "Name": "ExpectedValues", "Value": "

Expected values

A Lp(a) concentration of 30 mg/dL corresponding to the 75th percentile in a male Caucasian reference population is widely used as cut‑off point or threshold value.

LREFMarcovina SM, Koschinsky ML. A Critical Evaluation of the Role of Lp(a) in Cardiovascular Disease: Can Lp(a) Be Useful in Risk Assessment? Semin Vasc Med 2002 Aug;2(3):335-344.
,
LREFShai I, Rimm EB, Hankinson SE, et al. Lipoprotein (a) and Coronary Heart Disease Among Women: Beyond a Cholesterol Carrier? Eur Heart J 2005;26:1633-1639.

The European Atherosclerosis Society recommends screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk and defines a desirable Lp(a) level ≤ 50 mg/dL.

LREFNordestgaard BG, Chapman MJ, Ray K, et al. Lipoprotein (a) as a cardiovascular risk factor: current status. Eur Heart J 2010 Dec;31(23):2844-2853.

However the NHLBI recommends to stop using data for total Lp(a) mass, and to use nmol/L units instead, which consider the number of particles. Additionally they recommend to use assays independent from apo(a) size and standardized according to the IFCC reference material SRM2B.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Based on the evaluation of Framingham data values above 75 nmol/L are regarded as a cut‑off value for the presence of an increased risk.

LREFMarcovina SM, Koschinsky ML, Albers JJ, et al. Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 2003 Nov;49(11):1785-1796.

Elevated Lp(a) levels can be found in most racial/ethnicity groups, with the prevalence being lowest in whites and Asians. The median Lp(a) levels in black subjects and in Asian Indians from southern locations are 2‑ to 4‑fold higher compared with whites, and up to 68 % of blacks have Lp(a) levels > 75 nmol/L, whereas levels above this threshold are present in around 25 % of whites.

LREFTsimikas S, Clopton P, Brilakis ES, et al. Relationship of Oxidized Phospholipids on Apolipoprotein B-100 Particles to Race/Ethnicity, Apolipoprotein (a) Isoform Size, and Cardiovascular Risk Factors: Results From the Dallas Heart Study, Circulation 2009 Apr;119(13):1711-1719.

Therefore reference ranges have not been established for this assay for different ethnic populations or disease states. Since Lp(a) levels are largely influenced by hereditary factors and vary with ethnic populations it is recommended that each laboratory establish own expected values.

Each laboratory should investigate the transferability of the expected values to its own patient population and if necessary determine its own reference ranges.

", "Language": "en" }, { "Name": "LimitationInterference", "Value": "

Limitations – interference

Criterion: Recovery within ± 6 nmol/L of initial values of samples ≤ 60 nmol/L and within ± 10 % for samples > 60 nmol/L.

Icterus:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an I index of 60 for conjugated and unconjugated bilirubin (approximate conjugated and unconjugated bilirubin concentration: 1026 µmol/L or 60 mg/dL).

Hemolysis:

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an H index of 1000 (approximate hemoglobin concentration: 621 µmol/L or 1000 mg/dL).

Lipemia (Intralipid):

LREFGlick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-475.
No significant interference up to an L index of 2000. There is poor correlation between the L index (corresponds to turbidity) and triglycerides concentration.

Rheumatoid factors: No significant interference up to a level of 1200 IU/mL.

Plasminogen: No significant cross‑reactivity in the tested concentration range (up to 150 mg/dL).

Apolipoprotein B: No significant cross‑reactivity in the tested concentration range (up to 200 mg/dL).

Drugs: No interference was found at therapeutic concentrations using common drug panels.

LREFBreuer J. Report on the Symposium "Drug effects in Clinical Chemistry Methods". Eur J Clin Chem Clin Biochem 1996;34:385-386.
,
LREFSonntag O, Scholer A. Drug interference in clinical chemistry: recommendation of drugs and their concentrations to be used in drug interference studies. Ann Clin Biochem 2001;38:376-385.

High dose hook‑effect: No false result occurs up to a lipoprotein (a) concentration of 450 nmol/L.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

LREFBakker AJ, Mücke M. Gammopathy interference in clinical chemistry assays: mechanisms, detection and prevention. Clin Chem Lab Med 2007;45(9):1240-1243.

For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

ACTION REQUIRED
Special Wash Programming: The use of special wash steps is mandatory when certain test combinations are run together on cobas c systems. The latest version of the carry‑over evasion list can be found with the NaOHD-SMS-SmpCln1+2-SCCS Method Sheets. For further instructions refer to the operator’s manual. cobas c 502 analyzer: All special wash programming necessary for avoiding carry‑over is available via the cobas link, manual input is required in certain cases.

Where required, special wash/carry‑over evasion programming must be implemented prior to reporting results with this test.

", "Language": "en" }, { "Name": "OrderInformation", "Value": "

OrderInformation (CC Reagents - cobas + Integra)

Analyzer(s) on which cobas c pack(s) can be used

05852625 190

Tina‑quant Lipoprotein (a) Gen.2 (150 tests)

System‑ID 07 7504 5

cobas c 311, cobas c 501/502

Materials required (but not provided):

05852641 190

Preciset Lp(a) Gen.2 ( 5 x 1 mL)

Codes 962‑966

05852650 190

PreciControl Lp(a) Gen.2 (Level Low 2 x 1 mL)
PreciControl Lp(a) Gen.2 (Level High 2 x 1 mL)

Code 137
Code 138

04489357 190

Diluent NaCl 9 % (50 mL)

System‑ID 07 6869 3

", "Language": "en" }, { "Name": "SystemInformation", "Value": "

System information

For cobas c 311/501 analyzers:

LPA2: ACN 723

For cobas c 502 analyzer:

LPA2: ACN 8723

", "Language": "en" }, { "Name": "Handling", "Value": "

Reagent handling

Ready for use

Carefully invert reagent container several times prior to use to ensure that the reagent components are mixed.

", "Language": "en" }, { "Name": "TestDefinition", "Value": "

Application for serum and plasma

cobas c 311 test definition

Assay type

2‑Point End

Reaction time / Assay points

10 / 26‑49

Wavelength (sub/main)

800 / 660 nm

Reaction direction

Increase

Unit

nmol/L

Reagent pipetting

Diluent (H2O)

R1

133 µL

R3

33 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

2.0 µL

0 µL

0 µL

Decreased

8.0 µL

10 µL

110 µL

Increased

2.0 µL

0 µL

0 µL

cobas c 501 test definition

Assay type

2‑Point End

Reaction time / Assay points

10 / 40‑60

Wavelength (sub/main)

800 / 660 nm

Reaction direction

Increase

Unit

nmol/L

Reagent pipetting

Diluent (H2O)

R1

133 µL

R3

33 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

2.0 µL

0 µL

0 µL

Decreased

8.0 µL

10 µL

110 µL

Increased

2.0 µL

0 µL

0 µL

cobas c 502 test definition

Assay type

2‑Point End

Reaction time / Assay points

10 / 40‑60

Wavelength (sub/main)

800 / 660 nm

Reaction direction

Increase

Unit

nmol/L

Reagent pipetting

Diluent (H2O)

R1

133 µL

R3

33 µL

Sample volumes

Sample

Sample dilution

Sample

Diluent (NaCl)

Normal

2.0 µL

0 µL

0 µL

Decreased

8.0 µL

10 µL

110 µL

Increased

4.0 µL

0 µL

0 µL

", "Language": "en" }, { "Name": "StorageStability", "Value": "

Storage and stability

LPA2

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

6 weeks

Diluent NaCl 9  %

Shelf life at 2‑8 °C:

See expiration date on cobas c pack label.

On‑board in use and refrigerated on the analyzer:

12 weeks

", "Language": "en" }, { "Name": "Calibration", "Value": "

Calibration

Calibrators

S1: H2O
S2‑S6: Preciset Lp(a) Gen.2

Calibration mode

Spline

Calibration frequency

Full calibration
‑ after reagent lot change
‑ as required following quality control procedures

Calibration interval may be extended based on acceptable verification of calibration by the laboratory.

Traceability: This method has been standardized against the IFCC reference material SRM2B for nmol/L.

LREFMarcovina SM, Albers JJ, Scanu AM, et al. Use of a reference Material Proposed by the International federation of Clinical Chemistry and Laboratory Medicine to Evaluate Analytical methods for the Determination of Plasma Lipoprotein (a). Clin Chem 2000 Dec;46(12):1956-1967.

", "Language": "en" }, { "Name": "Limitations", "Value": "", "Language": "en" }, { "Name": "PerformanceData", "Value": "

Specific performance data

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

", "Language": "en" }, { "Name": "Precision", "Value": "

Precision

Repeatability and intermediate precision were determined using human samples and controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP5 requirements (2 aliquots per run, 2 runs per day, 21 days). The following results were obtained:

Repeatability

Sample

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control level L

40.7

0.6

1.5

Lp (a) Control level H

156

2

1.1

Human serum 1

18.2

1.0

5.6

Human serum 2

88.7

2.2

2.5

Human serum 3

226

2

0.8

Intermediate precision

Sample

Mean
nmol/L

SD
nmol/L

CV
%

Lp (a) Control level L

40.7

0.7

1.7

Lp (a) Control level H

156

2

1.2

Human serum 1

18.2

1.5

8.0

Human serum 2

88.7

2.7

3.0

Human serum 3

226

2

1.1

The data obtained on cobas c 501 analyzer(s) are representative for cobas c 311 analyzer(s).

", "Language": "en" }, { "Name": "MethodComparison", "Value": "

Method comparison

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 501 analyzer (y) were compared with those determined using the corresponding reagent on COBAS INTEGRA 800 analyzers (x).

Sample size (n) = 240

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 0.980x - 0.285 nmol/L

y = 0.985x - 0.745 nmol/L

τ = 0.938

r = 0.999

The sample concentrations were between 7.61 and 234 nmol/L.

Lipoprotein (a) values for human serum and plasma samples obtained on a cobas c 501 analyzer (y) were compared with those determined using the Northwest Lipid Metabolism and Diabetes Research Laboratories ELISA method traceable to the WHO/IFCC reference material SRM2B (x).

Sample size (n) = 105

Passing/Bablok

LREFBablok W, Passing H, Bender R, et al. A general regression procedure for method transformation. Application of linear regression procedures for method comparison studies in clinical chemistry, Part III. J Clin Chem Clin Biochem 1988 Nov;26(11):783-790.

Linear regression

y = 0.935x + 0.606 nmol/L

y = 0.942x + 0.105 nmol/L

τ = 0.947

r = 0.995

The sample concentrations were between 7.10 and 218 nmol/L.

The data obtained on cobas c 501 analyzer(s) are representative for cobas c 311 analyzer(s).

", "Language": "en" }, { "Name": "Summary", "Value": "

Summary

Lipoprotein (a) is composed of an LDL‑like particle to which the lipoprotein (a)‑specific apolipoprotein (a) is bonded by a disulfide bridge. Apolipoprotein (a) is highly homologous to plasminogen. Lipoprotein (a) is a cholesterol‑rich lipoprotein which is synthesized in the liver independently of triglycerides and is not subject to the influence of age or diet.

LREFSiekmeier R, Scharnagl H, Kostner GM, et al. Lipoprotein(a) - Structure, Epidemiology, Function and Diagnostics of a Cardiovascular Risk Marker. The Open Clin Chem J 2008;1:79-91.

Several unrelated studies showed that Lp(a) is an independent prospective risk factor for coronary heart disease. However acceptance is limited due to the fact that it is difficult to compare Lp(a) results between different clinical studies and the assays used showed strong variations and miscellaneous standardization levels.

LREFKamstrup PR. Lipoprotein(a) and Ischemic Heart Disease- A Causal Association? A review: Atherosclerosis 2010 Jul;211(1):15-23.
,
LREFGenser B, Dias KC, Siekmeier R, et al. Lipoprotein(a) and Risk of Cardiovascular Disease - A Systematic Review and Meta Analysis of Prospective Studies. Clin Lab 2011;57(3-4):143-156.

Main problem for accurate detection of Lp(a) is the size polymorphism of apolipoprotein a (apo (a)). Levels of Lp(a) vary drastically among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene on chromosome 6.

LREFKamstrup PR, Tybjaerg-Hansen A, Steffensen R, et al. Genetically Elevated Lipoprotein(a) and Increased Risk of Myocardial Infarction. JAMA 2009;301(22):2331-2339.
,
LREFClarke R, Peden JF, Hopewell JC, et al. Genetic Variants Associated with Lp(a) Lipoprotein Level and Coronary Disease. N Engl J Med 2009 Dec;361(26):2518-2528.

The high variable number of KRINGLE 4 type2 domains results in an apo (a) size ranging from 187 kDa to over 662 kDa. Assays with antibodies directed against this variable part of the Lp(a) molecule will underestimate Lp(a) in patients with apo (a) smaller than in the used calibrator and overestimate Lp(a) in such samples with larger apo (a) particles as in the calibrator. Based on the size heterogeneity it makes no sense to measure Lp(a) mass. Therefore the values should be expressed in terms of nanomoles per liter of Lp(a) protein.

Only standardization of these assays against an apo (a) size independent method will yield correct results. Such methods use antibodies that recognize a single copy of apo (a) per particle. By using the WHO/IFCC International Reference Reagent (SRM2B) this goal can be reached.

LREFDati F, Tate JR, Marcovina SM, et al. First WHO/IFCC International reference Reagent for Lipoprotein(a) for immunoassay - Lp(a) SRM2B. Clin Chem Lab Med 2004;42(6):670-676.
The value in this material has been assigned by using two different ELISA's based on monoclonal antibodies specific to two different unique epitopes present in apo (a).
LREFMarcovina SM, Albers JJ, Gabel B, et al. Effect of the Number of Apolipoprotein (a) Kringle 4 Domains on Immunochemical Measurements of Lipoprotein(a). Clin Chem 1995 Feb;41(2):246-255.
,
LREFMarcovina SM, Albers JJ, Wijsman E, et al. Differences in Lp(a) Concentrations and Apo(a) Polymorphs Between Black and White Americans. J Lipid Res 1996 Dec;37(12):2569-2585.
High lipoprotein (a) concentrations in serum correlate with premature manifestation of atherosclerosis and strokes. When lipoprotein (a) concentrations exceed 75 nmol/L, the coronary risk is approximately doubled. In combination with elevated LDL‑cholesterol concentrations, the risk increases approximately 6‑fold. An elevated lipoprotein (a) level is considered to be the most sensitive parameter for the development of coronary heart disease, irrespective of other plasma lipoproteins. Lipoprotein (a) should be determined together with total cholesterol, HDL‑cholesterol and LDL‑cholesterol as well as triglycerides when assessing the total arteriosclerotic risk.

According to the European Atherosclerosis Society Lp(a) measurement should be recommended in selected cases at high risk and in subjects with a family history of premature cardio vascular disease.

LREFReiner Ž, Catapano AL, De Backer G, et al. ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J 2011;32:1769-1818.

", "Language": "en" }, { "Name": "Reagents", "Value": "

Reagents - working solutions

R1

Glycine buffer: 170 mmol/L, pH 7.0; stabilizers; BSA; rabbit serum 0.1 %, preservative

R3

Latex particles coated with polyclonal anti‑human lipoprotein(a) antibodies (rabbit); glycine buffer: 170 mmol/L, pH 7.3, BSA; preservative

R1 is in position B and R3 is in position C.

", "Language": "en" }, { "Name": "PrecautionsWarnings", "Value": "

Precautions and warnings

For in vitro diagnostic use for health care professionals. Exercise the normal precautions required for handling all laboratory reagents.

Infectious or microbial waste:
Warning: handle waste as potentially biohazardous material. Dispose of waste according to accepted laboratory instructions and procedures.

Environmental hazards:
Apply all relevant local disposal regulations to determine the safe disposal.

Safety data sheet available for professional user on request.

", "Language": "en" }, { "Name": "Caution", "Value": "", "Language": "en" }, { "Name": "QualityControl", "Value": "

Quality control

For quality control, use control materials as listed in the \"Order information\" section.

In addition, other suitable control material can be used.

The control intervals and limits should be adapted to each laboratory’s individual requirements. Values obtained should fall within the defined limits. Each laboratory should establish corrective measures to be taken if values fall outside the defined limits.

Follow the applicable government regulations and local guidelines for quality control.

", "Language": "en" }, { "Name": "SpecimenPreparation", "Value": "

Specimen collection and preparation

For specimen collection and preparation only use suitable tubes or collection containers.

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: Li‑heparin or K2‑EDTA and K3‑EDTA plasma.

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, i.e. not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

With K3‑EDTA tubes pay particular attention that the tubes are adequately filled.

Centrifuge samples containing precipitates before performing the assay.

See the limitations and interferences section for details about possible sample interferences.

Stability:

If samples are not assayed within 8 hours, samples should be stored at 2‑8 °C.

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.

If samples are not assayed within 48 h,

LREFNational Committee for Clinical Laboratory Standards, Procedures for the handling and Processing of Blood Specimens, Approved Guideline, NCCLS publication H18-A, Villanova, 1990.
samples should be stored frozen at -70 °C or below.
LREFSimó JM, Camps J, Vilella E, et al. Instability of Lipoprotein (a) in Plasma Stored at -70 °C: Effects of Concentration, Apolipoprotein (a) Genotype, and Donor Cardiovascular Disease. Clin Chem 2001 Sep;47(9):1673-1678.
,
LREFSgoutas DS, Tuten T. Effect of Freezing and Thawing of Serum on the Immunoassay of Lipoprotein(a). Clin Chem 1992;38(9):1873-1877.
Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.

", "Language": "en" } ] } } ] }

LPA2

Tina-quant Lipoprotein (a) Gen.2

IVD For in vitro diagnostic use.
LPA2

Overview

Detailed Specifications

Ordering Information

Compatible Instruments

...
    ...

    Technical Documents

    Access Material Data Sheets, Certificates of Analysis, and other product documentation.

    After clicking below, you will be redirected to eLabDoc, where you can choose your local country.
    error errorMessage
    Sorry, we couldn't find the content you are looking for
    Please try again later