An unusual case of ascites.

A 76-year-old woman with abdominal pain and diarrhoea developed ascites that did not respond to treatment. There were no signs of liver damage. Abdominal ultrasonography with colour Doppler revealed an arterial-like flow in the enlarged splenic vein. Using selective mesenteric arteriography, we were able to diagnose a shunt between the inferior mesenteric artery and the inferior mesenteric vein. This is an unusual case of ascites due to prehepatic portal hypertension secondary to an extrahepatic arterioportal fistula.