Comparison of Prothrombin Time and Aspartate Aminotransferase in Predicting Hepatotoxicity After Acetaminophen Overdose.
Despite decades of experience with acetaminophen (APAP) overdoses, it remains unclear whether elevated hepatic transaminases or coagulopathy develop first. Furthermore, comparison of the predictive value of these two variables in determining hepatic toxicity following APAP overdoses has been poorly elucidated. The primary objective of this study is to determine the test characteristics of the aspartate aminotransferase (AST) and the prothrombin time (PT) in patients with APAP toxicity. A retrospective chart review of APAP overdoses treated with IV N-acetylcysteine at a tertiary care referral center was performed. Of the 304 subjects included in the study, 246 with an initial AST less than 1000 were analyzed to determine predictors of hepatic injury, defined as an AST exceeding 1000 IU/L. The initial AST >50 was 79.5 % sensitive and 82.6 % specific for predicting hepatic injury. The corresponding negative and positive predictive values were 95.5 and 46.3 %, respectively. In contrast, an initial abnormal PT had a sensitivity of 82.1 % and a specificity of 63.6 %. The negative and positive predictive values for initial PT were 94.9 and 30.2 %, respectively. Although the two tests performed similarly for predicting a composite endpoint of death or liver transplant, neither was a useful predictor. Initial AST performed better than the initial PT for predicting hepatic injury in this series of patients with APAP overdose.
Department of Emergency Medicine, Division of Medical Toxicology, University of Southern California, Los Angeles, CA, USA. mdlevine@usc.edu.|Department of Medical Toxicology, Banner Good Samaritan Medical Center, Phoenix, AZ, USA. mdlevine@usc.edu.
Michael
M
Levine
Department of Medical Toxicology, Banner Good Samaritan Medical Center, Phoenix, AZ, USA.|Center for Toxicology and Pharmacology, Education, and Research, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.
Ayrn D
AD
O'Connor
Banner Research Institute, Phoenix, AZ, USA.
Angela
A
Padilla-Jones
Center for Toxicology and Pharmacology, Education, and Research, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.|Banner Research Institute, Phoenix, AZ, USA.|Department of Internal Medicine, Banner Good Samaritan Medical Center, Phoenix, AZ, USA.
Richard D
RD
Gerkin
D000082:Acetaminophen / Q000506:poisoning*; D000111:Acetylcysteine / Q000627:therapeutic use; D000328:Adult; D018712:Analgesics, Non-Narcotic / Q000506:poisoning*; D000931:Antidotes / Q000627:therapeutic use; D019540:Area Under Curve; D001219:Aspartate Aminotransferases / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001777:Blood Coagulation / Q000187:drug effects*; D056486:Chemical and Drug Induced Liver Injury / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control; D004796:Clinical Enzyme Tests; D062787:Drug Overdose / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011517:Prothrombin Time; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult
D018712:Analgesics, Non-Narcotic; D000931:Antidotes; D015415:Biomarkers; D000082:Acetaminophen; D001219:Aspartate Aminotransferases; D000111:Acetylcysteine
Acetaminophen; Coagulopathy; Hepatic failure; Overdose