VIPoma

Case history

A 59-year-old woman presents with a 3-month history of profuse watery diarrhoea, weakness, and dehydration. Examination reveals poor skin turgor. Blood test results show severe hypokalaemia (2.1 mmol/L [2.1 mEq/L]), hypercalcaemia (2.79 mmol/L [11.2 mg/dL]), low bicarbonate (17 mmol/L [17 mEq/L]), and metabolic acidosis (pH 7.26).