K Number
K131544
Manufacturer
Date Cleared
2013-07-17

(49 days)

Product Code
Regulation Number
862.1110
Reference & Predicate Devices
Predicate For
N/A
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

cobas c Bilirubin Total Gen.3 is an in vitro test for the quantitative determination of total bilirubin in serum and plasma of adults and neonates on Roche/Hitachi cobas c systems. Measurement of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological, and metabolic disorders, including hepatitis and gall bladder block.

Device Description

cobas c Bilirubin Total Gen.3 reagent provides quantitative measurement of the total bilirubin that is present in serum and plasma of adults and neonates. Reagents are packaged in a cassette with two bottles labeled with their instrument positioning, R1 (Reagent 1) and R2 (Reagent 2). R1 contains detergent, buffer, and stabilizers at pH 1.0. R2 is a 3,5-dichlorophenyl diazonium salt: ≥ 1.35 mmol/L.

AI/ML Overview

The provided text describes the 510(k) summary for the cobas c Bilirubin Total Gen.3 device, a quantitative colorimetric method for determining total bilirubin in serum and plasma. The acceptance criteria and supporting studies are detailed for various performance characteristics.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

Performance CharacteristicAcceptance CriteriaReported Device Performance
PrecisionNot explicitly stated as a single criterion, but implied by the detailed imprecision (SD & CV%) requirements generally found in CLSI EP5-A2 studies.Repeatability (Within Run Imprecision): - PCCC1: 0.02 mg/dL (2.1% CV) - PCCC2: 0.02 mg/dL (0.6% CV) - Human Serum 1 (0.51 mg/dL): 0.01 mg/dL (2.9% CV) - Human Serum 2 (17.7 mg/dL): 0.10 mg/dL (0.6% CV) - Human Serum 3 (31.8 mg/dL): 0.14 mg/dL (0.4% CV) Intermediate Precision (Total Imprecision): - PCCC1: 0.02 mg/dL (2.1% CV) - PCCC2: 0.03 mg/dL (0.8% CV) - Human Serum 1 (0.51 mg/dL): 0.02 mg/dL (3.3% CV) - Human Serum 2 (17.7 mg/dL): 0.14 mg/dL (0.8% CV) - Human Serum 3 (31.8 mg/dL): 0.18 mg/dL (0.6% CV)
Linearity/Measuring RangeFor both serum and plasma, the first-order (linear) regression must be significant.Serum: Range tested and found: 0.12-38.9 mg/dL. Recommended measuring range: 0.15-35.1 mg/dL. Linear Regression: y=1.0021x-0.0317, r² = 0.999881 (Significant). Plasma: Range tested and found: 0.12-39.0 mg/dL. Recommended measuring range: 0.15-35.1 mg/dL. Linear Regression: y = 1.0014x - 0.0232, r² = 0.999954 (Significant).
Detection Limit (LoB, LoD, LoQ)Not explicitly stated in terms of acceptance criteria values, but the reported claims represent the specifications. The LoQ is determined based on precision at 20% CV.LoB claim: 0.10 mg/dL LoD claim: 0.15 mg/dL LoQ claim: 0.15 mg/dL
Analytical Specificity (Endogenous Substances)Lipemia: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤± 10% for samples > 1 mg/dL Hemolysis HbA: ≤±0.20 mg/dL for samples ≤ 2 mg/dL or ≤± 10% for samples > 2 mg/dL Hemolysis HbF: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤ ± 10% for samples > 1 mg/dL Indican: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤± 10% for samples > 1 mg/dLLipemia: No significant interference up to an L index of 1000. (Tested up to 1196-1217 L index) Hemolysis HbA: No significant interference up to an H index of 800. (Tested up to 946-951 H index) Hemolysis HbF: No significant interference up to an H index of 1000. (Tested up to 1047-1053 H index) Indican: No significant interference from indican up to 3 mg/dL. (Tested up to 3.75 mg/dL)
Analytical Specificity (Common Drugs)Difference in recovery to the reference sample: ≤± 10%All tested drugs (Acetylcystein, Ampicillin - Na, Ascorbic acid, Phenylbutazone, Cyclosporine A, Cefoxitin, Levodopa, Methyldopa + 1.5, Metronidazole, Doxycyclin, Acetylsalycilic acid, Rifampicin, Acetaminophen, Ibubrofen, Theophylline) passed the acceptance criteria at their respective highest concentrations.
Matrix Comparison (Anticoagulants)For sample concentrations ≤ 0.99 mg/dL, the deviation must be ≤ ± 0.10 mg/dL. For sample concentrations > 0.99 mg/dL, the deviation must be ≤± 10%.All data passed the criteria. - Li-Heparin (full & half), K2-EDTA (full & half), and Gel Separation Tube showed acceptable recovery within the tested ranges (e.g., Li-Heparin full: 0.35 - 34.52 mg/dL). - Serum vs. Li-heparin: y = 1.000x + 0.000, r = 0.9998
Adult Method Comparison with Predicate DeviceNot explicitly stated with a numerical criterion, but the strong correlation (r=0.9997) and the regression equation (y = 0.959x + 0.091 mg/dL) demonstrate substantial agreement.Equation: y = 0.959x + 0.091 mg/dL Correlation coefficient: r = 0.9997

2. Sample Size Used for the Test Set and Data Provenance

  • Precision:
    • Human Sera Samples: 3 samples (0.51, 17.7, and 31.8 mg/dL)
    • Control Samples: 2 serum-based control samples (PCCC1, PCCC2)
    • Each sample/control run in two aliquots per run, two runs per day for 21 days.
    • Data Provenance: Not explicitly stated, but implied to be laboratory-generated (not from real patient populations with specific countries of origin). Retrospective or prospective is not specified, but the study design suggests prospective lab testing.
  • Linearity/Assay Reportable Range:
    • Serum dilution series: 14 levels
    • Plasma dilution series: 13 levels
    • Data Provenance: Laboratory-generated, with human serum/plasma pool spiked with unconjugated bilirubin. Not specified for country of origin or retrospective/prospective.
  • Detection Limits (LoB, LoD, LoQ):
    • LoB: One blank sample
    • LoD: Five low-analyte samples
    • LoQ: A low-level sample set of nine
    • Data Provenance: Laboratory-generated.
  • Analytical Specificity (Endogenous Substances):
    • Interferents: Hemoglobin, lipids, indican.
    • Two pools of human serum used (one spiked, one unspiked) to create dilution series.
    • Interference tested at two levels of bilirubin.
    • Data Provenance: Laboratory-generated using human serum.
  • Analytical Specificity (Common Drugs):
    • 15 commonly used drugs.
    • Serum sample pools at two target concentrations of total bilirubin (~1.0 mg/dL and ~14.0 mg/dL).
    • Data Provenance: Laboratory-generated using serum.
  • Adult Method Comparison with Predicate Device:
    • Sample Size: n=131 human sera adult samples.
    • Data Provenance: Not explicitly stated for country of origin or retrospective/prospective, but implies de-identified human serum samples.
  • Matrix Comparison (Anticoagulants):
    • Sample Size: 35 tubes collected per anticoagulant type (Li-heparin, K2-EDTA, Gel Separation Tube).
    • Data Provenance: Not explicitly stated for country of origin or retrospective/prospective, but implies human plasma/serum samples.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This device is an in vitro diagnostic (IVD) for quantitative measurement of total bilirubin. Expert consensus is not typically used to establish ground truth for this type of quantitative biochemical assay. The ground truth is generally established by:

  • Reference Methods: For this device, the "ground truth" or reference method for traceability is explicitly stated as "Standardized against the Doumas manual reference method."
  • Predicate Device: For method comparison, the predicate device (Total Bilirubin reagent on the cobas c 501) serves as the comparator.

Therefore, the concept of "experts" in the context of clinical interpretation for ground truth is not applicable here.

4. Adjudication Method for the Test Set

Adjudication methods (e.g., 2+1, 3+1) are typically used in studies where human readers provide subjective assessments (e.g., image interpretation). This is a quantitative chemical assay, where measurements are objective. Therefore, no adjudication method was used or is relevant.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs without AI Assistance

No MRMC comparative effectiveness study was done. This device is a fully automated in vitro diagnostic test for measuring bilirubin levels. It does not involve human readers for interpretation, nor does it incorporate AI (Artificial Intelligence) in a way that would assist human readers.

6. If a Standalone (i.e., Algorithm Only Without Human-in-the-Loop Performance) Was Done

Yes, a standalone study was done. The entire performance evaluation (precision, linearity, detection limits, interference, method comparison) described in the document is for the device operating as a standalone quantitative assay without human intervention in the measurement process. The "algorithm" here refers to the chemical reaction principles and photometric measurement methodology.

7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, Etc.)

The ground truth for the quantitative measurement of total bilirubin is generally established by:

  • Reference Methods: The device is standardized against the Doumas manual reference method (as stated under "Traceability"). This is the gold standard for bilirubin measurement.
  • Comparator Methods: In the adult method comparison study, the predicate device (Total Bilirubin reagent) values served as the comparator for assessing agreement.

8. The Sample Size for the Training Set

The provided document describes a 510(k) submission for a diagnostic test. Unlike AI/ML-based diagnostic devices, this type of device does not typically involve "training sets" in the machine learning sense. The "training" in developing such a device involves refining chemical reagents and optimizing instrument parameters, which is a different process than training an algorithm on a dataset. The studies described are performance validation studies.

9. How the Ground Truth for the Training Set Was Established

As explained above, there isn't a "training set" in the context of an AI/ML algorithm for this type of IVD device. The development process would involve optimizing the reagent formulation and assay conditions against an established reference method (like the Doumas method) to ensure accurate and precise measurements.

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Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health & Human Services logo on the left and the FDA logo on the right. The FDA logo features the letters 'FDA' in a blue square, followed by the words 'U.S. FOOD & DRUG ADMINISTRATION' in blue text.

March 14, 2019

Roche Diagnostics Lisa Klinedinst 9115 South Hague Road Indianapolis, IN 46250

Re: K131544

Trade/Device Name: cobas c Bilirubin Total Gen.3 Regulation Number: 21 CFR 862.1110 Regulation Name: Bilirubin (total or direct) test system Regulatory Class: Class II Product Code: CIG, MOM Dated: May 28, 2013 Received: May 29, 2013

Dear Lisa Klinedinst:

This letter corrects our substantially equivalent letter of July 17, 2013.

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part

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801 and Part 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Kellie B. Kelm -S

Courtney H. Lias, Ph.D. for Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): K131544

Device Name: cobas c Bilirubin Total Gen.3

Indications for Use:

cobas c Bilirubin Total Gen.3 is an in vitro test for the quantitative determination of total bilirubin in serum and plasma of adults and neonates on Roche/Hitachi cobas c systems. Measurement of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological, and metabolic disorders, including hepatitis and gall bladder block.

Prescription Use X (21 CFR Part 801 Subpart D) And/Or

Over the Counter Use (21 CFR Part 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE; CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of In Vitro Diagnostics and Radiological Health (OIR)

Yung W. Chan -S

Division Sign-Off Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K131544

Page 1 of __ 1_

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016_510k Summary

ﺎ ﺳﺮ

510(k) Summary for cobas c Bilirubin Total Gen.3

JUL 1 7 2013

Date prepared:July 17, 2013
Purpose ofsubmissionRoche Diagnostics hereby submits this 510(k) to provide FDA withnotification of intent to market a new device named cobas c Bilirubin TotalGen.3 reagent. All data in this submission was generated on the cobas c 501analyzer.This candidate device is a new reagent that was developed by RocheDiagnostics. The previous generation of reagent, Total Bilirubin, was clearedin 510(k) K063543 and serves as the predicate device. The candidate andpredicate devices use the same calibrator and controls. Only the reagentsdiffer. This submission presents data to support clearance of this newreagent.
MeasurandTotal Bilirubin
Type of testQuantitative colorimetric method
ApplicantLisa K. KlinedinstRoche Diagnostics9115 South Hague RoadIndianapolis, IN 46250Telephone: (317) 521-1942Fax: (317) 521-2324Email: Lisa.Klinedinst@roche.com
Candidatedevice namesProprietary name:cobas c Bilirubin Total Gen.3Common name:Bilirubin Total Gen.3
RegulatoryinformationProduct CodeClassificationRegulationPanel
CIGClass II21 CFR 862.1110(Bilirubin (total or direct)test system)ClinicalChemistry

Continued on next page

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Intended useIn vitro test for the quantitative determination of total bilirubin in serum and plasma of adults and neonates on Roche/Hitachi cobas c systems.
Indications for usecobas e Bilirubin Total Gen.3 is an in vitro test for the quantitative determination of total bilirubin in serum and plasma of adults and neonates on Roche/Hitachi cobas c systems. Measurement of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological, and metabolic disorders, including hepatitis and gall bladder block.
Special conditions for useFor prescription use only
Special instrument requirementsFor use on the Roche/Hitachi cobas e clinical chemistry analyzer
Candidate device descriptioncobas e Bilirubin Total Gen.3 reagent provides quantitative measurement of the total bilirubin that is present in serum and plasma of adults and neonates. Reagents are packaged in a cassette with two bottles labeled with their instrument positioning, R1 (Reagent 1) and R2 (Reagent 2). R1 contains detergent, buffer, and stabilizers at pH 1.0. R2 is a 3,5-dichlorophenyl diazonium salt: ≥ 1.35 mmol/L.
Predicate deviceRoche Diagnostics claims substantial equivalence to the Total Bilirubin reagent on the cobas c 501. The reagent was originally cleared in K981632 on the Boehringer Mannheim/Hitachi 917 analyzer, and later cleared in a Special 510(k) K063543 on COBAS INTEGRA and Roche/Hitachi clinical chemistry analyzers. The application to the cobas c 501 analyzer was cleared on October 3, 2006 in K060373/A001 following the FDA Policy Document "Replacement Reagent and Instrument Family Policy - 12/11/2003". Continued on next page

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The following table compares the identical features of the candidate device to Substantial equivalence the predicate device that was cleared in 510(k) K063543. similarities

FeaturePredicate Device:Total BilirubinCandidate Device:Bilirubin Total Gen.3
Intended UseIn vitro test for the quantitativedetermination of total bilirubin inserum and plasma of adults andneonates on Roche/Hitachi cobas csystems.Same
Sample TypesSerum and plasma of adults andneonatesSame
PermissibleAnticoagulantsLi-heparinK2-EDTASame
Reference MethodDiazo colorimetric methodSame
CalibratorCalibrator for automated systems(C.f.a.s.) and deionized water as thezero calibrator(C.f.a.s. cleared for use with TotalBilirubin in 510(k) K101456)Same
Calibration StabilityRecalibrate with each lot and asrequired following quality controlproceduresSame
Reagent Shelf LifeStability2-8 °C until expiration dateSame
Calibration ModeLinear regressionSame
TraceabilityStandardized against the Doumasmanual reference methodSame
Instrument PlatformRoche/Hitachi cobas c 501Same

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The following table compares the different features of the candidate device to Substantial the predicate device that was cleared in 510(k) K063543. equivalence differences

Predicate Device:Candidate Device:
FeatureTotal BilirubinBilirubin Total Gen.3
Reagent CompositionRI:Sulfamic acid 110 mmol/L,Sodium Acetate Buffer 85mmol/L,Surfactant, and SolubilizerR1:Detergent, Buffer, and Stabilizersat pH 1.0
R2:Diazonium ion 3 mmol/L,HC1 100 mmol/LR2:3,5-Dichlorophenyl diazonium salt≥ 1.35 mmol/L
Reagent On-BoardStabilityon-board in use and refrigeratedon the analyzers: 5 weekson-board in use and refrigerated onthe analyzers: 6 weeks
ControlsPrecinorm U plus,Precipath U plus,Precinorm U,Precipath U(Controls above cleared for usewith Total Bilirubin in 510(k)K042389)Precinorm U plus,Precipath U plus,PreciControl ClinChem Multi 14.PreciControl ClinChem Multi 24AThese two new controls werecleared for use with TotalBilirubin with 510(k) K102016.

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Substantial equivalence - differences continued

FeaturePredicate Device:Total BilirubinCandidate Device:Bilirubin Total Gen.3
Measuring Range0.10 - 35.1 mg/dL0.146 - 35.1 mg/dL
Expected ValuesAdults and children:up to 1.0 mg/dLAdults: up to 1.2 mg/dL
Children with age ≥ 1 month:up to 1.0 mg/dL
NeonatesAge of Newborn: Premature
24 hours 1.0-6.0 mg/dLNewborns: Term and near-termAge of Newborn:
48 hours 6.0-8.0 mg/dL
3-5 days 10.0-15.0 mg/dL
Age of Newborn: Full Term
24 hours 2.0-6.0 mg/dL
48 hours 6.0-7.0 mg/dL3-5 days 10.0-12.0 mg/dL24 hours ≥ 8.0 mg/dL48 hours ≥ 13.0 mg/dL84 hours ≥ 17.0 mg/dL
Lower Limits ofMeasurementLDL = 0.10 mg/dLLoB = 0.10 mg/dLLoD = 0.15 mg/dLLoQ = 0.15 mg/dL

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cobas c Bilirubin Total Gen.3 measures total bilirubin by employing the diazo Test principle colorimetric method. Total bilirubin, in the presence of a suitable solubilizing agent, is coupled with a diazonium ion in a strongly acidic medium. The color intensity of the red azo dye formed is directly proportional to the total bilirubin and can be determined photometrically.

Precision was determined according to CLSI EP5-A2. The study included Precision/ reproducibility human sera samples (0.51, 17.7, and 31.8 mg/dL) and two serum-based control samples in two aliquots per run and two runs per day for 21 days.

Here are summaries of the repeatability and intermediate precision data.

Repeatability Summary
SpecimenPCCC1*PCCC2*Human Serum 1Human Serum 2Human Serum 3
Total Mean (mg/dL)0.903.090.5117.731.8
Within Run ImprecisionSD (mg/dL)0.020.020.010.100.14
Within Run ImprecisionCV%2.10.62.90.60.4
Min (mg/dL)0.853.030.4617.3631.41
Max (mg/dL)0.943.150.5517.9532.43

Intermediate Precision

SpecimenPCCC1*PCCC2*Human Serum 1Human Serum 2Human Serum 3
Total Mean (mg/dL)0.903.090.5117.731.8
Total ImprecisionSD (mg/dL)0.020.030.020.140.18
Total ImprecisionCV%2.10.83.30.80.6
Min (mg/dL)0.853.030.4617.3631.41
Max (mg/dL)0.943.150.5517.9532.43

Values that appear in bold type also appear in the labeling.

*PCCC1 = PreciControl ClinChem Multi 1

*PCCC2 = PreciControl ClinChem Multi 2

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Linearity was assessed according to CLSI EP6-A with one batch of reagent, Linearity/ assay reportable in one run, and with samples measured in triplicate. Two separate dilution range series differing by sample type (serum and plasma) were prepared with thirteen levels for the plasma series and fourteen levels for the serum series. Lithium-heparin was used to prepare the plasma sample series. The highest concentration samples exceed the desired measuring range. The highest concentration samples were created by taking a human serum/plasma sample pool and spiking it with unconjugated bilirubin.

Measuring Ranges that are Supported by the Linearity Data (mg/dL)

PlasmaSerum
Range tested0.12-39.00.12-38.9
Range found0.12-39.00.12-38.9
Recommended measuring range0.15-35.10.15-35.1

The first order (linear) regression is significant for both sample types.

Linear Regression Equation for Serum r2 = 0.999881 y=1.0021x-0.0317

Linear Regression Equation for Plasma r2 = 0.999954 y = 1.0014x - 0.0232

This method has been standardized against the manual test performance using Traceability and stability the Doumas method.

The reagent has been evaluated for transport, shelf-life, and open on-board stability.

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LoB, LoD, and LoQ studies were performed based upon CLSI EP17-A2. Detection limit

LoB Protocol: One blank sample was tested in n=5 with two analyzers with three reagent batches for six runs per day across three days.

LoD Protocol: Five low-analyte samples were measured in singlicate on two analyzers with three reagent batches for six runs per day across three days.

LoQ Protocol: A low-level sample set of nine was measured in singlicate, using three reagent batches on two analyzers for six runs per day across three days. The LoQ is determined based on precision at 20% CV.

The LoB, LoD, and LoQ claims represent the specifications for each.

LoB claim = 0.10 mg/dL LoD claim = 0.15 mg/dL LoQ claim = 0.15 mg/dL

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Analvtical specificity interference from endogenous substances

The reagent was evaluated with three endogenous substances, hemoglobin, lipids, and indican for potential interference with the measurement of total bilirubin.

One pool of human serum was spiked with the interferent. A second pool of human serum contained none. The two pools were mixed in different ratios to vield a dilution series with varying concentrations of the interferent.

The endogenous interference data are summarized in the table. Interference was tested at two levels of bilirubin.

no interference up toClaim as it appears in thelabeling.
Lipemia Level 11196 L indexNo significant interference up
Lipemia Level 21217 L indexto an L index of 1000.
Hemolysis HbA Level 1946 H indexNo significant interference up
Hemolysis HbA Level 2951 H indexto an H index of 800.
*Hemolysis HbF Level 11053 H indexNo significant interference up
*Hemolysis HbF Level 21047 H indexto an H index of 1000.
Indican Level 13.75 mg/dLNo significant interference
Indican Level 23.75 mg/dLfrom indican up to 3 mg/dL.

*HbF was tested for hemolysis interference in neonates.

All data passed the following acceptance criteria:

Lipemia: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤± 10% for samples > 1 mg/dL

Hemolysis HbA: ≤±0.20 mg/dL for samples ≤ 2 mg/dL or ≤± 10% for samples > 2 mg/dL.

Hemolysis in neonates - HbF: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤ ± 10% for samples > 1 mg/dL

Indican: ≤± 0.10 mg/dL for samples ≤ 1 mg/dL or ≤± 10% for samples > 1 mg/dL

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Fifteen commonly used drugs were examined for potential interference on Analytical specificity measurement with cobas c Bilirubin Total Gen.3 reagent. interference from common Drug interference testing was performed with serum sample pools at two drugs target concentrations of total bilirubin, one at a low concentration of ~ 1.0 mg/dL and the second one at a high concentration of ~ 14.0 mg/dL.

Total bilirubin concentration in all aliquots is measured in triplicate. The mean value among the triplicates for each aliquot is determined. From the mean values, the percent recovery to the initial value (no drug in sample) is calculated.

DrugHighest Concentration ShownNot to Interfere with BILT3(drug concentrations in mg/L)
1Acetylcystein150
2Ampicillin - Na1000
3Ascorbic acid300
4Phenylbutazone400
5Cyclosporine A5
6Cefoxitin2500
7Levodopa20
8Methyldopa + 1.520
9Metronidazole200
10Doxycyclin50
11Acetylsalycilic acid1000
12Rifampicin60
13Acetaminophen200
14Ibubrofen500
15Theophylline100

The table below summarizes the common drug interferences data:

All data passed the following acceptance criteria:

Difference in recovery to the reference sample: ≤± 10%

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Adult methodcomparisonwith predicatedeviceTotal bilirubin values for n=131 human sera adult samples were obtainedusing the candidate reagent (y-axis) to the predicate reagent (x-axis) on theRoche/Hitachi cobas c 501 analyzer. Candidate sample concentrationsranged from 0.18 to 30.38 mg/dL, and they were tested in singlicate. Thevalues were regressed using the Passing/Bablok model to produce thefollowing equation.
$y = 0.959x + 0.091 mg/dL$
$r = 0.9997$

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Lithium-heparin and K2-EDTA are permissible anticoagulants for use with Matrix this reagent because they do not interfere with recovery of total bilirubin. In comparison an internal study, 35 tubes were collected per anticoagulant. Plasma results were compared to serum results and percent recovery was determined. In terms of % recovery. All data passed the following criteria: For sample concentrations ≤ 0.99 mg/dL, the deviation must be ≤ ± 0.10

mg/dL. For sample concentrations > 0.99 mg/dL, the deviation must be ≤± 10%.

anticoagulantsSample concentrationrange tested (mg/dL)Claimed MeasuringRange (mg/dL)
Li-Heparin (full)0.35 - 34.52
Li-Heparin (half)0.84 - 31.650.15 - 35.1
K2-EDTA (full)0.36 - 34.46
K2-EDTA (half)0.80 - 31.18
Gel Separation Tube0.36 - 34.40

In addition, method comparisons with plasma vs serum were calculated with the following results:

Serum vs. Li-heparin > P/B: y = 1.000x + 0.000, r = 0.9998
Serum vs. K2-EDTA

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Expectedvalues/reference rangeAdults¹up to 1.2 mg/dL
Children with age ≥ 1 month¹up to 1.0 mg/dL
Newborns: Term and near-term²
Age of Newborn:
24 hours≥ 8.0 mg/dL
48 hours≥ 13.0 mg/dL
84 hours≥ 17.0 mg/dL
1. Thomas L. Labor und Diagnose. Indikation und Bewertung vonLaborbefunden fur die Medizinische Diagnostik. 7th ed. TH-BooksVerlagsgesellschaft 2007:259-273.
2. Subcommittee on Hyperbilirubinemia. Management ofHyperbilirubinemia in the Newborn Infant 35 or More Weeks ofGestation. Pediatrics 2004; 114: 297-316.

1


§ 862.1110 Bilirubin (total or direct) test system.

(a)
Identification. A bilirubin (total or direct) test system is a device intended to measure the levels of bilirubin (total or direct) in plasma or serum. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal distruction of red blood cells, if used in the diagnosis and treatment of liver, hemolytic hematological, and metabolic disorders, including hepatitis and gall bladder block.(b)
Classification. Class II.