The CEDIA Gentamicin II Assay is an in vitro diagnostic medical device intended for the quantitation of gentamicin in human serum or plasma.

The CEDIA Gentamicin II Assay uses recombinant DNA technology to produce a unique homogeneous enzyme immunoassay system.

Measuring range

0.24‑12.0 µg/mL (0.5‑25.1 µmol/L)

Specimen dilution

Manually dilute samples above the measuring range 1 + 1 with the CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay. Multiply the result by 2 and subtract the concentration of the low calibrator to obtain the specimen value.

Lower limits of measurement

Analytical sensitivity (lower detection limit): 0.24 μg/mL (0.5 μmol/L).

Specimens results below 0.24 μg/mL should be reported as <0.24 μg/mL. Specimens results greater than 12 μg/mL should be reported as >12 μg/mL or dilute 1 part sample with 1 part CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay.

The therapeutic efficacy and toxic effects are closely related to the serum drug concentration. In most adults a peak therapeutic response is achieved with gentamicin concentrations between 5‑8 μg/mL. Trough concentrations between 1‑2 μg/mL usually ensure that drug elimination is adequate.

Increasing total serum protein levels to 12.5 g/dL by addition of gamma globulin up to 5.0 g/dL; or increasing total serum protein levels to 12.5 g/dL by addition of human serum albumin up to 5.5 g/dL had no effect on patient sample quantitation by the assay.

Patient samples containing sisomicin will elevate gentamicin results.

The incidence of patients with antibodies to E. coli β‑galactosidase is extremely low. However, some samples containing such antibodies can result in artificially high gentamicin results that do not fit the clinical profile. If this occurs, contact Customer Technical Support.

As with any assay employing mouse antibodies, the possibility exists for interference by human anti‑mouse antibodies (HAMA) in the sample, which could cause falsely elevated 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, 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.

CEDIA™ Gentamicin II

^{a) Not all products are available in all countries.}

^{b) Catalog number is for USA only. Open/Close tool is available upon request in other countries.}

GENTC: ACN 8606

Remove the kit from refrigerated storage immediately prior to preparation of the solutions. Prepare the solutions in the following order to minimize possible contamination.

R2 Enzyme donor solution: Connect Bottle R2a (ED Reagent) to Bottle R2 (ED Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R2a is transferred into Bottle R2. Avoid the formation of foam. Detach Bottle R2a and adapter from Bottle R2 and discard. Cap Bottle R2 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

R1 Enzyme acceptor solution: Connect Bottle R1a (EA Reagent) to Bottle R1 (EA Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R1a is transferred into Bottle R1. Avoid the formation of foam. Detach Bottle R1a and adapter from Bottle R1 and discard. Cap Bottle R1 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

Filling the cobas c pack:

1. Turn the cobas c pack toward you.

2. Position B of the cobas c pack is on the left side and position C on the right side.

3. Unscrew the screw cap of the bottle in position B on the left side of the cobas c pack using the Open/Close tool.

4. Use one of the enclosed funnels to pour the content of the R1 bottle (13.0 mL) into the opened bottle of the cobas c pack (position B). Discard the funnel.

5. Close the bottle tightly using the Open/Close tool.

6. Unscrew the screw cap of the bottle in position C on the right side of the cobas c pack using the Open/Close tool.

7. Use one of the enclosed funnels to pour the content of the R2 bottle (11.0 mL) into the opened bottle of the cobas c pack (position C). Discard the funnel.

8. Close the bottle tightly using the Open/Close tool.

The CEDIA Gentamicin II cobas c pack is now ready for use.

NOTE: Solutions must be at the reagent compartment storage temperature of the analyzer before performing assays.

Always use a new cobas c pack when preparing fresh reagent. Never reuse accessories designed for single use, as this may result in reagent contamination and could affect test results. If the cobas c pack bottles are not filled correctly, this may result in faulty reagent pipetting and could cause erroneous results.

Deselect Automatic Rerun for these applications in the Utility menu, Application screen, Range tab.

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

Traceability: This method has been standardized against USP reference standards. The CEDIA Antibiotic TDM Multi‑Cal calibrators are prepared to contain known quantities of gentamicin in bovine serum albumin.

Representative performance data on the Roche/Hitachi 704 analyzer are given below. Results obtained in individual laboratories may differ

Intra‑assay precision was determined by assaying 20 replicates of each of 3 control pools while inter‑assay precision was determined by single point quantitation on 64 runs. The following results were obtained.

A comparison using the CEDIA Gentamicin Assay (y) with a commercially available FPIA (x) gave the following correlation (μg/mL).

Linear regression

y = 0.98x + 0.17

r = 0.992

Sy.x = 0.347

Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by E. coli, Klebsiella, Enterobacter, Proteus mirabilis, Pseudomonas aeruginosa, Serratia, Staphylococcus aureus, Staphylococcus epidermidis and other microorganisms. Gentamicin’s toxic effect is produced by interfering with ribosomal protein synthesis.

Danger

• R1 & R2 Reconstitution Buffers: Contain sodium azide.

EUH032 – Contact with acids liberates very toxic gas.

• R1a & R2a Reagents: Contain goat serum, BSA, sodium phosphate (dibasic, anhydrous), sodium phosphate (monobasic), sodium azide, drug-specific monoclonal antibody (mouse).

EUH032 – Contact with acids liberates very toxic gas.

Avoid breathing mist or vapor. Wash hands thoroughly after handling. Contaminated work clothing should not be allowed out of the workplace. Wear protective gloves/eye protection/face protection. In case of inadequate ventilation wear respiratory protection. IF ON SKIN: Wash with plenty of soap and water. IF INHALED: If breathing is difficult, remove victim to fresh air and keep at rest in a position comfortable for breathing. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. If skin irritation or rash occurs: Get medical advice/attention. If eye irritation persists: Get medical advice/attention. If experiencing respiratory symptoms: Call a POISON CENTER or doctor/physician. Take off contaminated clothing and wash before reuse. Dispose of contents/container to location in accordance with local/regional/national/international regulations.

Sodium azide may react with lead or copper plumbing to form potentially explosive metal azides. When disposing of such reagents, always flush with large volumes of water to prevent azide build‑up. Clean exposed metal surfaces with 10 % sodium hydroxide.

• Do not use the reagents beyond their expiration dates.

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 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: Na- or Li-heparin, Na-EDTA

Serum or plasma (Na- or Li-heparin; Na-EDTA) samples are suitable for use in the assay. Care should be taken to preserve the chemical integrity of the serum or plasma sample from the time it is collected until the time it is assayed. Cap samples, store at 2‑8 °C and assay within 1 week after collection. If the assay cannot be performed within 1 week, or if the sample is to be shipped, cap the sample and keep it frozen. Store samples at -20 °C and assay within 4 weeks.

Invert thawed specimens several times prior to testing.

To protect the integrity of the sample, do not induce foaming and avoid repeated freezing and thawing. Centrifuge specimens containing particulate matter. Handle all patient samples as if they were potentially infectious.

Centrifuge samples containing precipitates before performing the assay.

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

The CEDIA Gentamicin II Assay is an in vitro diagnostic medical device intended for the quantitation of gentamicin in human serum or plasma.

The CEDIA Gentamicin II Assay uses recombinant DNA technology to produce a unique homogeneous enzyme immunoassay system.

Measuring range

0.24‑12.0 µg/mL (0.5‑25.1 µmol/L)

Specimen dilution

Manually dilute samples above the measuring range 1 + 1 with the CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay. Multiply the result by 2 and subtract the concentration of the low calibrator to obtain the specimen value.

Lower limits of measurement

Analytical sensitivity (lower detection limit): 0.24 μg/mL (0.5 μmol/L).

Specimens results below 0.24 μg/mL should be reported as <0.24 μg/mL. Specimens results greater than 12 μg/mL should be reported as >12 μg/mL or dilute 1 part sample with 1 part CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay.

The therapeutic efficacy and toxic effects are closely related to the serum drug concentration. In most adults a peak therapeutic response is achieved with gentamicin concentrations between 5‑8 μg/mL. Trough concentrations between 1‑2 μg/mL usually ensure that drug elimination is adequate.

Increasing total serum protein levels to 12.5 g/dL by addition of gamma globulin up to 5.0 g/dL; or increasing total serum protein levels to 12.5 g/dL by addition of human serum albumin up to 5.5 g/dL had no effect on patient sample quantitation by the assay.

Patient samples containing sisomicin will elevate gentamicin results.

The incidence of patients with antibodies to E. coli β‑galactosidase is extremely low. However, some samples containing such antibodies can result in artificially high gentamicin results that do not fit the clinical profile. If this occurs, contact Customer Technical Support.

As with any assay employing mouse antibodies, the possibility exists for interference by human anti‑mouse antibodies (HAMA) in the sample, which could cause falsely elevated results.

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

^{a) Not all products are available in all countries.}

GENTC: ACN 21480

Remove the kit from refrigerated storage immediately prior to preparation of the solutions. Prepare the solutions in the following order to minimize possible contamination.

R2 Enzyme donor solution: Connect Bottle R2a (ED Reagent) to Bottle R2 (ED Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R2a is transferred into Bottle R2. Avoid the formation of foam. Detach Bottle R2a and adapter from Bottle R2 and discard. Cap Bottle R2 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

R1 Enzyme acceptor solution: Connect Bottle R1a (EA Reagent) to Bottle R1 (EA Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R1a is transferred into Bottle R1. Avoid the formation of foam. Detach Bottle R1a and adapter from Bottle R1 and discard. Cap Bottle R1 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

Filling the cobas c pack:

1. Turn the cobas c pack toward you.

2. Position B of the cobas c pack is on the left side and position C on the right side.

3. Unscrew the screw cap of the bottle in position B on the left side of the cobas c pack using the Open/Close tool.

4. Use one of the enclosed funnels to pour the content of the R1 bottle (13.0 mL) into the opened bottle of the cobas c pack (position B). Discard the funnel.

5. Close the bottle tightly using the Open/Close tool.

6. Unscrew the screw cap of the bottle in position C on the right side of the cobas c pack using the Open/Close tool.

7. Use one of the enclosed funnels to pour the content of the R2 bottle (11.0 mL) into the opened bottle of the cobas c pack (position C). Discard the funnel.

8. Close the bottle tightly using the Open/Close tool.

The CEDIA Gentamicin II cobas c pack is now ready for use.

NOTE: Solutions must be at the reagent compartment storage temperature of the analyzer before performing assays.

Always use a new cobas c pack when preparing fresh reagent. Never reuse accessories designed for single use, as this may result in reagent contamination and could affect test results. If the cobas c pack bottles are not filled correctly, this may result in faulty reagent pipetting and could cause erroneous results.

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 USP reference standards. The CEDIA Antibiotic TDM Multi‑Cal calibrators are prepared to contain known quantities of gentamicin in bovine serum albumin.

Representative performance data on the Roche/Hitachi 704 analyzer are given below.

Results obtained in individual laboratories may differ.

Intra‑assay precision was determined by assaying 20 replicates of each of 3 control pools while inter‑assay precision was determined by single point quantitation on 64 runs. The following results were obtained.

Precision was determined using TDM controls in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP05‑A3 requirements with repeatability (n = 80) and intermediate precision (2 aliquots per run, 2 runs per day, 20 days). Results for repeatability and intermediate precision were obtained on the cobas c 503 analyzer.

^{a) TDM Control Set Level I}

^{b) TDM Control Set Level II}

^{c) TDM Control Set Level III}

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

A comparison using the CEDIA Gentamicin Assay (y) with a commercially available FPIA (x) gave the following correlation (μg/mL).

Linear regression

y = 0.98x + 0.17

r = 0.992

Sy.x = 0.347

Gentamicin 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).

The sample concentrations were between 0.44 and 11.64 µg/mL.

Gentamicin 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).

The sample concentrations were between 0.31 and 8.47 µg/mL.

Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by E. coli, Klebsiella, Enterobacter, Proteus mirabilis, Pseudomonas aeruginosa, Serratia, Staphylococcus aureus, Staphylococcus epidermidis and other microorganisms. Gentamicin’s toxic effect is produced by interfering with ribosomal protein synthesis.

Danger

• R1 & R2 Reconstitution Buffers: Contain sodium azide.

EUH032 – Contact with acids liberates very toxic gas.

• R1a & R2a Reagents: Contain goat serum, BSA, sodium phosphate (dibasic, anhydrous), sodium phosphate (monobasic), sodium azide, drug-specific monoclonal antibody (mouse).

EUH032 – Contact with acids liberates very toxic gas.

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 every cobas c pack change.

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: Na- or Li-heparin, Na-EDTA

Serum or plasma (Na- or Li-heparin; Na-EDTA) samples are suitable for use in the assay. Care should be taken to preserve the chemical integrity of the serum or plasma sample from the time it is collected until the time it is assayed. Cap samples, store at 2‑8 °C and assay within 1 week after collection. If the assay cannot be performed within 1 week, or if the sample is to be shipped, cap the sample and keep it frozen. Store samples at -20 °C and assay within 4 weeks.

Invert thawed specimens several times prior to testing.

To protect the integrity of the sample, do not induce foaming and avoid repeated freezing and thawing. Centrifuge specimens containing particulate matter. Handle all patient samples as if they were potentially infectious.

Centrifuge samples containing precipitates before performing the assay.

The CEDIA Gentamicin II Assay is an in vitro diagnostic medical device intended for the quantitation of gentamicin in human serum or plasma.

The CEDIA Gentamicin II Assay uses recombinant DNA technology to produce a unique homogeneous enzyme immunoassay system.

Measuring range

0.24‑12.0 µg/mL (0.5‑25.1 µmol/L)

Specimen dilution

Manually dilute samples above the measuring range 1 + 1 with the CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay. Multiply the result by 2 and subtract the concentration of the low calibrator to obtain the specimen value.

Lower limits of measurement

Analytical sensitivity (lower detection limit): 0.24 μg/mL (0.5 μmol/L).

Specimens results below 0.24 μg/mL should be reported as <0.24 μg/mL. Specimens results greater than 12 μg/mL should be reported as >12 μg/mL or dilute 1 part sample with 1 part CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay.

The therapeutic efficacy and toxic effects are closely related to the serum drug concentration. In most adults a peak therapeutic response is achieved with gentamicin concentrations between 5‑8 μg/mL. Trough concentrations between 1‑2 μg/mL usually ensure that drug elimination is adequate.

Increasing total serum protein levels to 12.5 g/dL by addition of gamma globulin up to 5.0 g/dL; or increasing total serum protein levels to 12.5 g/dL by addition of human serum albumin up to 5.5 g/dL had no effect on patient sample quantitation by the assay.

Patient samples containing sisomicin will elevate gentamicin results.

The incidence of patients with antibodies to E. coli β‑galactosidase is extremely low. However, some samples containing such antibodies can result in artificially high gentamicin results that do not fit the clinical profile. If this occurs, contact Customer Technical Support.

As with any assay employing mouse antibodies, the possibility exists for interference by human anti‑mouse antibodies (HAMA) in the sample, which could cause falsely elevated 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.

GENTC: ACN 21480

Remove the kit from refrigerated storage immediately prior to preparation of the solutions. Prepare the solutions in the following order to minimize possible contamination.

R2 Enzyme donor solution: Connect Bottle R2a (ED Reagent) to Bottle R2 (ED Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R2a is transferred into Bottle R2. Avoid the formation of foam. Detach Bottle R2a and adapter from Bottle R2 and discard. Cap Bottle R2 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

R1 Enzyme acceptor solution: Connect Bottle R1a (EA Reagent) to Bottle R1 (EA Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R1a is transferred into Bottle R1. Avoid the formation of foam. Detach Bottle R1a and adapter from Bottle R1 and discard. Cap Bottle R1 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

Filling the cobas c pack:

1. Turn the cobas c pack toward you.

2. Position B of the cobas c pack is on the left side and position C on the right side.

3. Unscrew the screw cap of the bottle in position B on the left side of the cobas c pack using the Open/Close tool.

4. Use one of the enclosed funnels to pour the content of the R1 bottle (13.0 mL) into the opened bottle of the cobas c pack (position B). Discard the funnel.

5. Close the bottle tightly using the Open/Close tool.

6. Unscrew the screw cap of the bottle in position C on the right side of the cobas c pack using the Open/Close tool.

7. Use one of the enclosed funnels to pour the content of the R2 bottle (11.0 mL) into the opened bottle of the cobas c pack (position C). Discard the funnel.

8. Close the bottle tightly using the Open/Close tool.

The CEDIA Gentamicin II cobas c pack is now ready for use.

NOTE: Solutions must be at the reagent compartment storage temperature of the analyzer before performing assays.

Always use a new cobas c pack when preparing fresh reagent. Never reuse accessories designed for single use, as this may result in reagent contamination and could affect test results. If the cobas c pack bottles are not filled correctly, this may result in faulty reagent pipetting and could cause erroneous results.

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 USP reference standards. The CEDIA Antibiotic TDM Multi‑Cal calibrators are prepared to contain known quantities of gentamicin in bovine serum albumin.

Representative performance data on the Roche/Hitachi 704 analyzer are given below. Results obtained in individual laboratories may differ.

Intra‑assay precision was determined by assaying 20 replicates of each of 3 control pools while inter‑assay precision was determined by single point quantitation on 64 runs. The following results were obtained.

A comparison using the CEDIA Gentamicin Assay (y) with a commercially available FPIA (x) gave the following correlation (μg/mL).

Linear regression

y = 0.98x + 0.17

r = 0.992

Sy.x = 0.347

Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by E. coli, Klebsiella, Enterobacter, Proteus mirabilis, Pseudomonas aeruginosa, Serratia, Staphylococcus aureus, Staphylococcus epidermidis and other microorganisms. Gentamicin’s toxic effect is produced by interfering with ribosomal protein synthesis.

Danger

• R1 & R2 Reconstitution Buffers: Contain sodium azide.

EUH032 – Contact with acids liberates very toxic gas.

• R1a & R2a Reagents: Contain goat serum, BSA, sodium phosphate (dibasic, anhydrous), sodium phosphate (monobasic), sodium azide, drug-specific monoclonal antibody (mouse).

EUH032 – Contact with acids liberates very toxic gas.

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 every cobas c pack change.

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: Na- or Li-heparin, Na-EDTA

Serum or plasma (Na- or Li-heparin; Na-EDTA) samples are suitable for use in the assay. Care should be taken to preserve the chemical integrity of the serum or plasma sample from the time it is collected until the time it is assayed. Cap samples, store at 2‑8 °C and assay within 1 week after collection. If the assay cannot be performed within 1 week, or if the sample is to be shipped, cap the sample and keep it frozen. Store samples at -20 °C and assay within 4 weeks.

Invert thawed specimens several times prior to testing.

To protect the integrity of the sample, do not induce foaming and avoid repeated freezing and thawing. Centrifuge specimens containing particulate matter. Handle all patient samples as if they were potentially infectious.

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.

The CEDIA Gentamicin II Assay is an in vitro diagnostic medical device intended for the quantitation of gentamicin in human serum or plasma.

The CEDIA Gentamicin II Assay uses recombinant DNA technology to produce a unique homogeneous enzyme immunoassay system.

Measuring range

0.24‑12.0 µg/mL (0.5‑25.1 µmol/L)

Specimen dilution

Manually dilute samples above the measuring range 1 + 1 with the CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay. Multiply the result by 2 and subtract the concentration of the low calibrator to obtain the specimen value.

Lower limits of measurement

Analytical sensitivity (lower detection limit): 0.24 μg/mL (0.5 μmol/L).

Specimens results below 0.24 μg/mL should be reported as <0.24 μg/mL. Specimens results greater than 12 μg/mL should be reported as >12 μg/mL or dilute 1 part sample with 1 part CEDIA Antibiotic TDM Multi‑Cal Low calibrator diluent (0 ng/mL) and reassay.

The therapeutic efficacy and toxic effects are closely related to the serum drug concentration. In most adults a peak therapeutic response is achieved with gentamicin concentrations between 5‑8 μg/mL. Trough concentrations between 1‑2 μg/mL usually ensure that drug elimination is adequate.

Increasing total serum protein levels to 12.5 g/dL by addition of gamma globulin up to 5.0 g/dL; or increasing total serum protein levels to 12.5 g/dL by addition of human serum albumin up to 5.5 g/dL had no effect on patient sample quantitation by the assay.

Patient samples containing sisomicin will elevate gentamicin results.

The incidence of patients with antibodies to E. coli β‑galactosidase is extremely low. However, some samples containing such antibodies can result in artificially high gentamicin results that do not fit the clinical profile. If this occurs, contact Customer Technical Support.

As with any assay employing mouse antibodies, the possibility exists for interference by human anti‑mouse antibodies (HAMA) in the sample, which could cause falsely elevated 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 required in certain cases.

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

CEDIA™ Gentamicin II

^{a) Not all products are available in all countries.}

^{b) Catalog number is for USA only. Open/Close tool is available upon request in other countries.}

For cobas c 501 analyzer:

GENTC: ACN 606

For cobas c 502 analyzer:

GENTC: ACN 8606

Remove the kit from refrigerated storage immediately prior to preparation of the solutions. Prepare the solutions in the following order to minimize possible contamination.

R2 Enzyme donor solution: Connect Bottle R2a (ED Reagent) to Bottle R2 (ED Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R2a is transferred into Bottle R2. Avoid the formation of foam. Detach Bottle R2a and adapter from Bottle R2 and discard. Cap Bottle 2 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

R1 Enzyme acceptor solution: Connect Bottle R1a (EA Reagent) to Bottle R1 (EA Reconstitution Buffer) using one of the enclosed adapters. Mix by gentle inversion, ensuring that all the lyophilized material from Bottle R1a is transferred into Bottle R1. Avoid the formation of foam. Detach Bottle R1a and adapter from Bottle 1 and discard. Cap Bottle 1 and let stand approximately 5 minutes at 15‑25 °C. Mix again. Record the reconstitution date on the bottle label. Place the bottle into refrigerated storage and let stand 30 minutes before use.

Filling the cobas c pack:

1. Turn the cobas c pack toward you.

2. Position A of the cobas c pack is now in the center, position B on the left side, position C on the right side of the cobas c pack.

3. Unscrew the screw cap of the bottle in position B on the left side of the cobas c pack using the Open/Close tool.

4. Use one of the enclosed funnels to pour the content of the R1 bottle (13.0 mL) into the opened bottle of the cobas c pack (position B). Discard the funnel.

5. Close the bottle tightly using the Open/Close tool.

6. Unscrew the screw cap of the bottle in position C on the right side of the cobas c pack using the Open/Close tool.

7. Use one of the enclosed funnels to pour the content of the R2 bottle (11.0 mL) into the opened bottle of the cobas c pack (position C). Discard the funnel.

8. Close the bottle tightly using the Open/Close tool.

9. Leave position A empty.

The CEDIA Gentamicin II cobas c pack is now ready for use.

NOTE: Solutions must be at the reagent compartment storage temperature of the analyzer before performing assays.

Always use a new cobas c pack when preparing fresh reagent. Never reuse accessories designed for single use, as this may result in reagent contamination and could affect test results. If the cobas c pack bottles are not filled correctly, this may result in faulty reagent pipetting and could cause erroneous results.

Deselect Automatic Rerun for these applications in the Utility menu, Application screen, Range tab.

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

Traceability: This method has been standardized against USP reference standards. The CEDIA Antibiotic TDM Multi‑Cal calibrators are prepared to contain known quantities of gentamicin in bovine serum albumin.

Representative performance data on the Roche/Hitachi 704 analyzer are given below. Results obtained in individual laboratories may differ.

Intra‑assay precision was determined by assaying 20 replicates of each of 3 control pools while inter‑assay precision was determined by single point quantitation on 64 runs. The following results were obtained.

A comparison using the CEDIA Gentamicin Assay (y) with a commercially available FPIA (x) gave the following correlation (μg/mL).

Linear regression

y = 0.98x + 0.17

r = 0.992

Sy.x = 0.347

Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by E. coli, Klebsiella, Enterobacter, Proteus mirabilis, Pseudomonas aeruginosa, Serratia, Staphylococcus aureus, Staphylococcus epidermidis and other microorganisms. Gentamicin’s toxic effect is produced by interfering with ribosomal protein synthesis.

Danger

• R1 & R2 Reconstitution Buffers: Contain sodium azide.

EUH032 – Contact with acids liberates very toxic gas.

• R1a & R2a Reagents: Contain goat serum, BSA, sodium phosphate (dibasic, anhydrous), sodium phosphate (monobasic), sodium azide, drug-specific monoclonal antibody (mouse).

EUH032 – Contact with acids liberates very toxic gas.

Avoid breathing mist or vapor. Wash hands thoroughly after handling. Contaminated work clothing should not be allowed out of the workplace. Wear protective gloves/eye protection/face protection. In case of inadequate ventilation wear respiratory protection. IF ON SKIN: Wash with plenty of soap and water. IF INHALED: If breathing is difficult, remove victim to fresh air and keep at rest in a position comfortable for breathing. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. If skin irritation or rash occurs: Get medical advice/attention. If eye irritation persists: Get medical advice/attention. If experiencing respiratory symptoms: Call a POISON CENTER or doctor/physician. Take off contaminated clothing and wash before reuse. Dispose of contents/container to location in accordance with local/regional/national/international regulations.

Sodium azide may react with lead or copper plumbing to form potentially explosive metal azides. When disposing of such reagents, always flush with large volumes of water to prevent azide build‑up. Clean exposed metal surfaces with 10 % sodium hydroxide.

• Do not use the reagents beyond their expiration dates.

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. 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: Na- or Li-heparin, Na-EDTA

Serum or plasma (Na- or Li-heparin; Na-EDTA) samples are suitable for use in the assay. Care should be taken to preserve the chemical integrity of the serum or plasma sample from the time it is collected until the time it is assayed. Cap samples, store at 2‑8 °C and assay within 1 week after collection. If the assay cannot be performed within 1 week, or if the sample is to be shipped, cap the sample and keep it frozen. Store samples at -20 °C and assay within 4 weeks.

Invert thawed specimens several times prior to testing.

To protect the integrity of the sample, do not induce foaming and avoid repeated freezing and thawing. Centrifuge specimens containing particulate matter. Handle all patient samples as if they were potentially infectious.

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.