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Updated: Jun 7, 2026
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Generation of a Rat Model of Acute Liver Failure by Combining 70% Partial Hepatectomy and Acetaminophen
Published on: November 27, 2019
When do the aminotransferases rise after acute acetaminophen overdose?
Thomas J Green1, Marco L A Sivilotti, Caillin Langmann
1Department of Emergency Medicine, Queen's University, Kingston, ON, Canada.
Clinical Toxicology (Philadelphia, Pa.)
|October 26, 2010
Summary
Aminotransferase (AT) levels rise quickly after acetaminophen overdose, indicating liver damage. Rapid AT increases and high initial levels predict severe poisoning and aid risk assessment.
Area of Science:
- Toxicology
- Hepatology
- Pharmacokinetics
Background:
- Aminotransferases (ATs), including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), are early indicators of acetaminophen (APAP) overdose-induced hepatotoxicity.
- The precise kinetics of AT elevation are not well-defined, limiting early prediction of severe outcomes.
Purpose of the Study:
- To characterize the release kinetics of aminotransferases in patients with acute APAP overdose who develop hepatotoxicity despite N-acetylcysteine treatment.
- To identify patterns in AT elevation that correlate with poisoning severity.
Main Methods:
- Retrospective analysis of 94 patients from the Canadian Acetaminophen Overdose Study (CAOS) with peak AT > 1,000 IU/L.
- Data collected included initial AT levels, time to presentation, and time to peak AT levels post-ingestion.
Main Results:
- Most patients presented with elevated AT levels (median 211 IU/L at 15.3 hours post-ingestion).
- Serum AT concentrations demonstrated rapid increases, with a median doubling time of 9.5 hours.
- Higher initial AT levels and faster doubling times were associated with more severe coagulopathy.
Conclusions:
- Rapidly rising and elevated aminotransferases at presentation are indicative of severe acetaminophen poisoning.
- Incorporating initial AT levels and their rate of change into risk prediction models may improve accuracy.
- Further research is needed to validate these kinetic parameters for clinical risk stratification.
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