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Human Liver Microphysiological System for Assessing Drug-Induced Liver Toxicity In Vitro
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False positive acetaminophen levels associated with hyperbilirubinemia
Michael C Beuhler1, Steven C Curry
1Carolinas Poison Center, Division of Medical Toxicology, Department of Emergency Medicine, Carolinas Medical Center, Charlotte, NC 28232, USA. Michael.beuhler@carolinashealthcare.org
Clinical Toxicology (Philadelphia, Pa.)
|May 21, 2005
Summary
Hyperbilirubinemia can cause false positive acetaminophen readings with the GDS assay. For accurate acetaminophen levels in jaundiced patients, use alternative methods like EMIT or GC/MS.
Area of Science:
- Clinical Chemistry
- Toxicology
- Analytical Chemistry
Background:
- Accurate serum acetaminophen measurement is crucial for managing hepatic failure.
- Hyperbilirubinemia can interfere with certain laboratory assays.
Purpose of the Study:
- To investigate false positive acetaminophen results in hyperbilirubinemic patients using the GDS Diagnostics enzymatic assay.
- To determine the interference threshold and linearity of bilirubin on acetaminophen quantification.
Main Methods:
- Analyzed samples from hyperbilirubinemic patients and bilirubin standards using GDS Diagnostics and EMIT acetaminophen assays.
- Verified acetaminophen absence via gas chromatography/mass spectroscopy (GC/MS).
- Assessed interference at varying total bilirubin concentrations.
Main Results:
- The GDS assay produced false positive acetaminophen results at total bilirubin levels as low as 15 mg/dL.
- EMIT assay and GC/MS did not detect acetaminophen in any tested samples.
- Significant interference was observed with the GDS assay in the presence of hyperbilirubinemia.
Conclusions:
- The GDS Diagnostics enzymatic assay for acetaminophen is unreliable in patients with hyperbilirubinemia.
- Alternative methods such as EMIT or GC/MS are recommended for accurate acetaminophen quantification in these patients.
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