In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay.

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L, 20‑600 mg/dL)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

Lower detection limit of the test

0.2 g/L (3.68 µmol/L, 20 mg/dL)

The lower detection limit represents the lowest measurable analyte level that can be distinguished from zero. It is calculated as the value lying 3 standard deviations above that of the lowest standard (standard 1 + 3 SD, repeatability, n = 21).

Values below the lower detection limit (< 0.2 g/L) will not be flagged by the instrument.

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L, 90‑200 mg/dL)

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

Criterion: Recovery within ± 10 % of initial value at an α1‑antitrypsin concentration of 0.9 g/L (16.6 µmol/L, 90 mg/dL).

Icterus:

Hemolysis:

Lipemia (Intralipid):

Rheumatoid factors up to 1200 IU/mL do not interfere.

High dose hook-effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L (221 µmol/L, 1200 mg/dL).

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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 Roche/Hitachi cobas c systems. All special wash programming necessary for avoiding carry‑over is available via the cobas link, manual input is not required. The latest version of the carry‑over evasion list can also 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.

AAT2: ACN 8048

Ready for use

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

Precision was determined using human samples and controls in an internal protocol with repeatability (n = 21) and intermediate precision (3 aliquots per run, 1 run per day, 21 days). The following results were obtained:

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

α1-Antitrypsin values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 701 analyzer (y) were compared with those determined using the corresponding reagent on a Roche/Hitachi cobas c 501 analyzer (x).

Sample size (n) = 95

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme-inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

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

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay.

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L, 20‑600 mg/dL)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

Lower detection limit of the test

0.2 g/L (3.68 µmol/L, 20 mg/dL)

The lower detection limit represents the lowest measurable analyte level that can be distinguished from zero. It is calculated as the value lying 3 standard deviations above that of the lowest standard (standard 1 + 3 SD, repeatability, n = 21).

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L, 90‑200 mg/dL)

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

Criterion: Recovery within ± 10 % of initial value at an α1-antitrypsin concentration of 0.9 g/L (16.6 µmol/L, 90 mg/dL).

Icterus:

Hemolysis:

Lipemia (Intralipid):

Rheumatoid factors up to 1200 IU/mL do not interfere.

High dose hook-effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L (221 µmol/L, 1200 mg/dL).

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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 Roche/Hitachi 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 not required.

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

For cobas c 311/501 analyzers:

AAT2: ACN 048

For cobas c 502 analyzer:

AAT2: ACN 8048

Ready for use

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

Traceability: This method has been standardized against the certified reference material in human serum of the IRMM (Institute for Reference Materials and Measurements) ERM‑DA470k/IFCC.

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

Precision was determined using human samples and controls in an internal protocol with repeatability (n = 21) and intermediate precision (3 aliquots per run, 1 run per day, 21 days). The following results were obtained:

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

α1‑Antitrypsin values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 501 analyzer (y) were compared with those determined using the corresponding reagent on a Roche/Hitachi 917 analyzer (x).

Sample size (n) = 119

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

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme‑inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

R1 is in position B and R2 is in position C.

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

In vitro test for the quantitative immunological determination of human α1‑antitrypsin in human serum and plasma on COBAS INTEGRA systems.

Immunoturbidimetric assay
Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically at 340 nm.

Measuring range

0.25‑5.50 g/L (4.60‑101 µmol/L or 25‑550 mg/dL) (typical measuring range)

The upper and lower limits of the measuring range depend on the actual calibrator value.

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.

Determine samples having lower concentrations via the rerun function. For samples with lower concentrations, the rerun function reduces the sample predilution factor to 10.5. The results are automatically multiplied by the reduced predilution factor.

Lower limits of measurement

Lower detection limit of the test:
0.2 g/L (3.68 µmol/L or 20.0 mg/dL)

The lower detection limit represents the lowest measurable analyte level that can be distinguished from zero. It is calculated as the value lying 3 standard deviations above that of a zero sample (zero sample + 3 SD, repeatability, n = 21).

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L or 90.0‑200 mg/dL)

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

Criterion: Recovery within ± 10 % of initial value.

Serum, plasma

Icterus:

Hemolysis:

Lipemia:

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

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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.

Test AAT2, test ID 0‑008.

Ready for use

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

Precision was determined using human samples and controls in an internal protocol with repeatability (n = 21) and intermediate precision (3 aliquots per run, 1 run per day, 10 days). The following results were obtained:

α1‑Antitrypsin values for human serum and plasma samples obtained on a COBAS INTEGRA 700 analyzer using the COBAS INTEGRA Tina-quant  α1‑Antitrypsin ver.2 reagent (y) were compared with those determined using the same reagent on a COBAS INTEGRA 400 analyzer (x) and to those determined on a commercially available alternative automated system (nephelometric determination) (x).

The sample concentrations were between 0.19 and 3.52 g/L (3.50 and 64.8 µmol/L or 19.0 and 352 mg/dL).

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme-inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

R1 is in position B and SR is position C.

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.

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

Only the specimens listed below were tested and found acceptable.
Serum
Plasma: heparin (Li-, Na-, NH₄⁺-) or EDTA (K₂-, K₃-) 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.

Samples and controls are automatically prediluted 1:21 (1+20) with NaCl solution by the instrument.

In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L, 20‑600 mg/dL)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

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 95^th 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 α1‑antitrypsin samples.

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L*, 90‑200 mg/dL*)

^{*calculated by unit conversion factor}

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

Criterion: Recovery within ± 10 % of initial value at an α1‑antitrypsin concentration of 0.9 g/L.

Icterus:

Hemolysis:

Lipemia (Intralipid):

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

High-dose hook effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L.

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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.

AAT2: ACN 20030

Ready for use

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

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

Traceability: This method has been standardized against the certified reference material in human serum of the IRMM (Institute for Reference Materials and Measurements) ERM‑DA470k/IFCC.

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.

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.

α1‑antitrypsin 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) = 72

The sample concentrations were between 0.270 and 5.46 g/L (27.0 and 546 mg/dL).

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme‑inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

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

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.

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

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

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.

In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

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 95^th 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 α1‑antitrypsin samples.

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L*)

^{*calculated by unit conversion factor}

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

Criterion: Recovery within ± 10 % of initial value at an α1-antitrypsin concentration of 0.9 g/L.

Icterus:

Hemolysis:

Lipemia (Intralipid):

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

High-dose hook effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L.

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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 Roche/Hitachi 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.

AAT2: ACN 20030

Ready for use

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

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

Traceability: This method has been standardized against the certified reference material in human serum of the IRMM (Institute for Reference Materials and Measurements) ERM‑DA470k/IFCC.

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.

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:

α1‑antitrypsin values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 503 analyzer (y) were compared with those determined using the corresponding reagent on a Roche/Hitachi cobas c 501 analyzer (x).

Sample size (n) = 72

The sample concentrations were between 0.270 and 5.46 g/L.

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme‑inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

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

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

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

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.

In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

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 95^th 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 α1‑antitrypsin samples.

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L*)

^{*calculated by unit conversion factor}

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

Criterion: Recovery within ± 10 % of initial value at an α1-antitrypsin concentration of 0.9 g/L.

Icterus:

Hemolysis:

Lipemia (Intralipid):

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

High-dose hook effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L.

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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

AAT2: ACN 20030

Ready for use

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

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

Traceability: This method has been standardized against the certified reference material in human serum of the IRMM (Institute for Reference Materials and Measurements) ERM‑DA470k/IFCC.

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.

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.

α1‑antitrypsin 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) = 72

The sample concentrations were between 0.270 and 5.46 g/L.

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme‑inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

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

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

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

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.

In vitro test for the quantitative determination of α1‑antitrypsin in human serum and plasma on Roche/Hitachi cobas c systems.

Immunoturbidimetric assay

Human α1‑antitrypsin forms a precipitate with a specific antiserum which is determined turbidimetrically.

Measuring range

0.2‑6.0 g/L (3.68‑110.4 µmol/L)

Determine samples having higher concentrations via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted using the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

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 95^th 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 α1‑antitrypsin samples.

Expected values

^LREFDati F, Schumann G, Thomas L, et al. Consensus of a group of professional societies and diagnostic companies on guidelines for interim reference ranges for 14 proteins in serum based on the standardization against the IFCC/BCR/CAP reference material (CRM 470). Eur J Clin Chem Clin Biochem 1996;34:517-520.

0.9‑2.0 g/L (16.6‑36.8 µmol/L*)

^{*calculated by unit conversion factor}

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

Criterion: Recovery within ± 10 % of initial value at an α1-antitrypsin concentration of 0.9 g/L.

Icterus:

Hemolysis:

Lipemia (Intralipid):

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

High-dose hook effect: No false result occurs up to an α1‑antitrypsin concentration of 12 g/L.

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

Elevated estrogen levels (oral contraceptives; third trimester of pregnancy) give rise to increased values. CRP and haptoglobin should therefore also be determined.

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

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

Materials required (but not provided):

AAT2: ACN 20030

Ready for use

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

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

Traceability: This method has been standardized against the certified reference material in human serum of the IRMM (Institute for Reference Materials and Measurements) ERM‑DA470k/IFCC.

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.

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.

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

α1‑antitrypsin 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) = 72

The sample concentrations were between 0.270 and 5.46 g/L.

Summary

^LREFLievens M, Bienvenu J, Buitrago JMG, et al. Evaluation of four new Tina-quant assays for determination of α1-acid glycoprotein, α1-antitrypsin, haptoglobin and prealbumin. Clin Lab 1996;42:515-520.

^,

^LREFGreiling H, Gressner AM, eds. Lehrbuch der Klinischen Chemie und Pathobiochemie, 3rd ed. Stuttgart/New York: Schattauer Verlag 1995:231-232.

^,

^LREFSchneider M, Pott G, Gerlach U. Alpha-1-Antitrypsin-Mangel. Klin Wschr 1986;64:197-205.

^,

^LREFTietz NW, ed. Clinical Guide to Laboratory Tests, 3rd ed. Philadelphia, PA: WB Saunders Company 1995;66-67.

^,

^LREFJohnson AM, Alper CA. Deficiency of α1-antitrypsin in childhood liver disease. Pediatrics 1970;46(6):921-925.

^,

^LREFSilverman EK, Pierce JA, Province MA, et al. Variability of pulmonary function in alpha-1-antitrypsin deficiency: Clinical correlates. Ann Intern Med 1989;111(12):982-991.

α1‑Antitrypsin is a glycoprotein consisting of a polypeptide chain to which 3 oligosaccharide chains are bonded (54000 daltons). It is synthesized in hepatocytes. α1‑Antitrypsin is quantitatively the most important proteinase inhibitor (Pi) in serum and plasma. It specifically inactivates serine proteases (e.g. trypsin, chymotrypsin, collagenase, leukocyte elastase, plasmin and thrombin), with which it reversibly forms an enzyme‑inhibitor complex. α1‑Antitrypsin constitutes the major fraction of the electrophoretic α1‑globulin fraction. Because it is a small molecule, α1‑antitrypsin diffuses rapidly into other body fluids including bronchial secretions.

α1‑Antitrypsin is an important, positive acute phase reactant found in elevated concentrations in inflammatory processes (e.g. infectious and rheumatoid diseases), tissue necrosis, malignancy and traumas. Inflammation of the liver parenchymal cells is often accompanied by elevated α1‑antitrypsin levels, although levels of other acute phase reactants are not affected.

Acute hereditary α1‑antitrypsin deficiency is suspected in cases of neonatal hepatitis accompanied by progressive liver cirrhosis in early childhood. It is also suspected when severe pulmonary emphysema occurs in adults due to the prevalence of leukocyte elastase, which can lead to unrestrained proteolytic degradation of the pulmonary parenchymal cells.

Various methods are available for assaying α1‑antitrypsin, such as kinetic nephelometry or radial immunodiffusion. Roche’s automated α1‑antitrypsin assay is based upon the immunological agglutination test principle.

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

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.

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 and K₂‑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.

Centrifuge samples containing precipitates before performing the assay.

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

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.