To investigate the role of echo-Doppler flowmetry in evaluating patients with cystic fibrosis and portal hypertension at risk of esophageal varices, we studied 26 subjects divided in 3 groups: 9 with portal hypertension and esophageal varices, 8 with chronic liver disease without varices, and 9 without chronic liver disease. Spleen size, diameter, blood velocity, and flow rate of portal, splenic, and superior mesenteric veins were recorded. In patients without chronic liver disease Doppler measurements were repeated on 2 different days to assess intraobserver variability. Significant differences among the three groups were found for mean values of spleen size and diameters of portal, splenic, and superior mesenteric veins. Nevertheless, a considerable overlapping of individual data was observed. No differences were observed in mean hemodynamic measurements, except for blood velocity in portal vein and flow rate in splenic vein. The intraobserver variability for repeated Doppler measurements was clinically unacceptable for most of the variables studied. Echo-Doppler assessment of splanchnic flow seems to be an unreliable tool in the management of cystic fibrosis patients with portal hypertension at risk of esophageal varices.