A 61-year-old woman transferred from a regional hospital due to acute renal failure. The patient reported severe diarrhoea and vomiting for a week. Her history included arterial hypertension and DM treated with irbesartan, amlodipine and metformin (850 mg/12 h). Examination revealed severe dehydration, tachypnoea and bradypsychia, although he was responsive to commands. The abdomen was soft and non-painful. Blood pressure was 90/40 mmHg, heart rate 70 beats/minute and temperature 35.8ºC. Table 2 shows the main analytical data. Serum amylase was 94 U/l. Fluid intake normalised blood pressure and the administration of 165 mEq of bicarbonate raised pH to 7.06 and bicarbonate to 4 mEq/l. The patient underwent urgent haemodialysis and metformin treatment was discontinued. Twelve hours after admission, creatinine was 2.2 mg/dl and pH 7.43, but amylase rose to 1,319 U/l, with normal ionic calcium and triglycerides. An abdominal CT scan revealed peripancreatic fatty infiltration with free abdominal fluid compatible with acute pancreatitis. No known causes of pancreatitis were found, including hypertriglyceridaemia, hypercalcaemia, alcoholism, biliary lithiasis or trauma. The patient progressed favourably and was transferred to the ward 72 hours after admission.