PurposeDue to the seroepidemiological shift in hepatitis A (HA), its severity, mortality, and complications have increased in recent years. Thus, the aim of this study was to identify predictive factors associated with poor prognosis among patients with HA.Materials and MethodsA total of 304 patients with HA admitted to our institution between July 2009 and June 2011 were enrolled consecutively. Patients with complications defined as acute liver failure (ALF) were evaluated, and mortality was defined as death or liver transplantation.ResultsThe mean age of patients (204 males, 100 females) was 32 years. Eighteen (5.9%) patients had progressed to ALF. Of the patients with ALF, 10 patients (3.3%) showed spontaneous survival while 8 (2.6%) died or underwent liver transplantation. Multivariate regression analysis showed that Model for End-Stage Liver Disease (MELD) and systemic inflammatory response syndrome (SIRS) scores were significant predictive factors of ALF. Based on receiver operating characteristics (ROC) analysis, a MELD ≥23.5 was significantly more predictive than a SIRS score ≥3 (area under the ROC: 0.940 vs. 0.742, respectively). In addition, of patients with a MELD score ≥23.5, King's College Hospital criteria (KCC) and SIRS scores were predictive factors associated with death/transplantation in multivariate analysis.ConclusionMELD and SIRS scores ≥23.5 and ≥3, respectively, appeared to be related to ALF development. In addition, KCC and SIRS scores ≥3 were valuable in predicting mortality of patients with a MELD ≥23.5.