Mortality due to severe or necrotizing acute pancreatitis most often results from multiorgan dysfunction syndrome (MODS) occurring either early (within the first 14 days) or 2 weeks or more after the onset of symptoms due to septic complications. The aim of this study was to analyse the course of the disease in patients who died from severe acute pancreatitis. Between January 1994 and August 2000 details of 263 consecutive patients with acute pancreatitis were entered prospectively into a database. All patients were treated in an intermediate or intensive care unit. The overall mortality rate was 4 per cent (ten of 263 patients). The mortality rate was 9 per cent (ten of 106) in patients with necrotizing disease. No patient died within the first 2 weeks of disease onset. The median day of death was 91 (range 15-209). Six patients died from septic MODS. Ranson score, Acute Physiology and Chronic Health Evaluation (APACHE) II score during the first week of disease, pre-existing co-morbidity, body mass index, infection and extent of necrosis were significantly associated with death (P < 0.01 for all parameters). However, only infection of the necrotic pancreas was an independent risk factor in the multivariate analysis. Early deaths in patients with severe acute pancreatitis are rare, mainly as a result of modern intensive care treatment. Nine of the ten deaths occurred more than 3 weeks after disease onset. Infection of pancreatic necrosis was the main risk factor for death.