A patient with neurofibromatosis type 1 and watery diarrhoea syndrome due to a VIP-producing adrenal phaeochromocytoma

A 43-year-old patient with neurofibromatosis type 1 suffered from watery di arrhoea syndrome induced by excessive production of vasoactive intestinal p olypeptide (VIP) in an adrenal phaeochromocytoma. This case report emphasiz es that patients with neurofibromatosis are prone to develop more than one disease induced by tumours originating from the neural crest. Since excessi ve VIP production in a phaeochromocytoma may mask the symptoms of catechola mine overproduction, and in view of the therapeutic consequences, neurofibr omatosis patients with hyperVIP-aemia must be checked for the presence of a phaeochromocytoma.