Background and aims: Amanita phalloides poisoning causes severe liver damage which may be potentially fatal. Several treatments are available, but their effectiveness has not been systematically evaluated. We performed a systematic review to investigate the effect of the most commonly used therapies: N-acetylcysteine (NAC), benzylpenicillin (PEN), and silibinin (SIL) on patient outcomes. In addition, other factors contributing to patient outcomes are identified.
Methods: We searched MEDLINE and Embase for case series and case reports that described patient outcomes after poisoning with amanitin-containing Amanita mushrooms. We extracted clinical characteristics, treatment details, and outcomes. We used the liver item from the Poisoning Severity Score (PSS) to categorize intoxication severity.
Results: We included 131 publications describing a total of 877 unique cases. The overall survival rate of all patients was 84%. Patients receiving only supportive care had a survival rate of 59%. The use of SIL or PEN was associated with a 90% (OR 6.40 [3.14-13.04]) and 89% (OR 5.24 [2.87-9.56]) survival rate, respectively. NAC/SIL combination therapy was associated with 85% survival rate (OR 3.85 [2.04, 7.25]). NAC/PEN/SIL treatment group had a survival rate of 76% (OR 2.11 [1.25, 3.57]). Due to the limited number of cases, the use of NAC alone could not be evaluated. Additional analyses in 'proven cases' (amanitin detected), 'probable cases' (mushroom identified by mycologist), and 'possible cases' (neither amanitin detected nor mushroom identified) showed comparable results, but the results did not reach statistical significance. Transplantation-free survivors had significantly lower peak values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total serum bilirubin (TSB), and international normalized ratio (INR) compared to liver transplantation survivors and patients with fatal outcomes. Higher peak PSS was associated with increased mortality.
Conclusion: Based on data available, no statistical differences could be observed for the effects of NAC, PEN or SIL in proven poisonings with amanitin-containing mushrooms. However, monotherapy with SIL or PEN and combination therapy with NAC/SIL appear to be associated with higher survival rates compared to supportive care alone. AST, ALT, TSB, and INR values are possible predictors of potentially fatal outcomes.
Keywords: Amatoxin; N-acetylcysteine; benzylpenicillin; silibinin; systematic review.