Chronic diarrhea due to VIPoma in two children.

The diagnosis of vasoactive intestinal poly-peptide-secreting tumor (VIPoma) was established in two boys on the basis of watery diarrhea with hypokalemia, elevated plasma levels of vasoactive intestinal polypeptide (VIP) (range of 55-94 pmol/L), and presence of a tumor of the left adrenal gland. Despite celiac angiography, VIP estimation in blood samples taken from different parts of the body, and exploratory laparotomy, localization of the tumor in one child in vivo was unsuccessful. In the other boy, computed tomography revealed a large tumor in the left adrenal gland.