REPEATED SUPRATHERAPEUTIC DOSING OF ACETAMINOPHEN (APAP): CAN SERUM TRANSAMINASE LEVELS PREDICT THE RISK OF HEPATOTOXICITY?

Objective: Repeated supratherapeutic dosing accounts for 9% of APAP-related deaths and has not been studied systematically. We hypothesize that AST/ALT at presentation identifies patients at risk for APAP-induced hepatotoxicity following repeated supratherapeutic dosing. Methods: A prospective cohort study of poison center patients presenting with repeated supratherapeutic APAP dosing (ingestion of [is greater than] 4 g/24 h; pediatric [is greater than] 90 mg/kg) was performed using structured data collection. Patients were managed by standing poison center protocol (presentation with abnormal AST/ALT or APAP level [is greater than] 10 mcg/mL prompted treatment with N-acetylcysteine-NAC) and followed for 48 hours, or until resolution of symptoms and laboratory abnormalities. Results: 44,689 calls were screened; 2,335 were APAP exposures. 114 cases (5%) were repeated supratherapeutic ingestions and 92 consented to enrollment. AST/ALT at Median Presentation n (%) APAP (g/d) Normal AST/ALT 41 (44.6) 10 AST/ALT >50 IU/L 40 (43.5) 12 No laboratory data 11 (11.9) 7.5 AST/ALT at Hepatotoxicity Lost to Presentation (AST > 1000 IU/L) Follow Up Normal AST/ALT 0 (15 treated with NAC) 7 AST/ALT >50 IU/L 13 (4 deaths, 1 transplant) 2 No laboratory data 0 (3 well at follow-up) 8 The likelihood ratio for patients with normal AST/ALT at presentation developing hepatotoxicity was zero. This study is limited by small numbers, administration of NAC to patients with normal AST, and 18% lost to follow-up rate. Conclusion: Patients who present after repeated supratherapeutic APAP ingestions with normal AST/ALT may not need treatment with NAC. The role of an APAP level in directing treatment and predicting outcome is not clear. Daly FFS, Dart RC, Bogdan GM, Jolliff HA, Waksman JC. Rocky Mountain Poison & Drug Center-Denver Health, University of Colorado Health Sciences Center, Denver, CO
Daly FFS, Dart RC, Bogdan GM, Jolliff HA, Waksman JC. Rocky Mountain Poison & Drug Center-Denver Health, University of Colorado Health Sciences Center, Denver, [...]