Confirming the Causative Role of Acetaminophen in Indeterminate Acute Liver Failure Using Acetaminophen-Cysteine Adducts.

Abstract

INTRODUCTION:

Acetaminophen-cysteine adducts (APAP-CYS) are a serum biomarker of acetaminophen exposure, formed when the oxidative metabolite of acetaminophen binds to cysteine residues of hepatic proteins. APAP-CYS adducts become elevated in cases of acute liver failure following acetaminophen overdose and have been proposed as a diagnostic tool to identify acetaminophen-induced acute liver failure when standard testing is inconclusive.

CASE REPORT:

A 26-year-old female with history of unexplained, severe hepatitis presented with a second episode of severe hepatitis including coagulopathy and transaminase levels >10,000 U/L. The patient reported ingesting "only a couple" of acetaminophen tablets several days prior to her presentation. An acetaminophen concentration of 14 mcg/mL at presentation aroused suspicion that acetaminophen might have caused the patient's liver failure, despite her adamant denial of overdose. APAP-CYS adduct levels measured from serum obtained 4 days after her presentation and in two consecutive serum samples are reported alongside previously reported APAP-CYS levels.

DISCUSSION:

The patient's APAP-CYS adduct levels were consistent with those seen in acute liver injury due to acetaminophen toxicity, even up to 1 week following presentation, and allowed for confirmation of acetaminophen toxicity as the cause of the her hepatitis. Overall, this case demonstrates the real-time application of APAP-CYS adducts as a biomarker to diagnose acetaminophen toxicity in patients with indeterminate acute liver failure.

• Authors: Sean M Frey, Timothy J Wiegand, Jody L Green, Kennon J Heard, Diana G Wilkins, Rachel M Gorodetsky, Richard C Dart
• Journal: Journal of medical toxicology : official journal of the American College of Medical Toxicology (J Med Toxicol) Vol. 11 Issue 2 Pg. 218-22 (Jun 2015) ISSN: 1937-6995 [Electronic] United States
• PMID: 25896948 (Publication Type: Case Reports, Journal Article)

Chemical References

• Analgesics, Non-Narcotic
• Biomarkers
• Acetaminophen
• acetaminophen cysteine
• Cysteine

Topics

• Acetaminophen (analogs & derivatives, analysis, poisoning)
• Adult
• Analgesics, Non-Narcotic (analysis, poisoning)
• Biomarkers (analysis)
• Centrifugation
• Cysteine (analogs & derivatives, analysis)
• Dialysis
• Drug Overdose (diagnosis)
• Female
• Humans
• Liver Failure, Acute (chemically induced, diagnosis)
• Liver Function Tests