In order to ascertain the clinical and epidemiological features of acute liver failure (ALF), we analyzed the clinical histories of 22 patients from La Plata city, with the diagnosis of ALF (prothrombin level or factor V below 50%) seen between November 1996 and November 2000. Age, sex, hepatic encephalopathy, reason for consultation, etiology, hepatic biochemical tests, serum creatinine, glycemia, digestive hemorrhage, course and treatment variables were analyzed. What is remarkable is the high frequency of the toxic etiology and of infection by HDV, as well as the high prevalence of ascites and the low incidence of hepatic encephalopathy. We think that the high survival rate we found is due to the early diagnosis and early referral of the patients to the intensive care unit and to centers with programs for liver transplantation.