Acute pancreatitis (AP) remains a subject of great controversy from the standpoint of its aetiology, pathogeny and treatment. We present a study of 91 patients with AP consecutively admitted to a surgical ward. 50 Women and 41 men with a mean age of 59 +/- 19 years were treated. The aetiology of AP was attributed to gallstones in 54 patients, alcohol in 22, ERPC and trauma; in 14 patients the aetiology was considered idiopathic. The most frequent signs and symptoms were pain, vomiting, abdominal tenderness, jaundice and fever. The mean number of Ranson's prognostic criteria was 3 +/- 1.5 and 29 patients (31%) had more than three. Initial management was conservative in 84 patients (92.3%) and seven were operated on admission (acute abdomen in four, septic shock in two and common duct obstruction in another). Mortality rate was 11% (n = 10) and in 24 patients (26.3%) there were complications of AP. Most of the patients (80%) began oral feeding a week after admission. The mean number of Ranson's criteria of patients deceased was 5.4 +/- 1.6 and of those who survived was 2.8 +/- 1.3 (p < 0.001). Follow-up of patients allowed us to see that in five (5.5%) there was a relapse of AP.