Watery diarrhea, hypokalemia and achlorhydria syndrome. Morphological and immunohistological study

A case of WDHA syndrome accompanied by a pancreatic tumor in a 44-year-old Japanese male is presented, the 6th case in Japan. Clinically, the patient suffered from unremitting watery diarrhea, hypokalemia and achlorhydria with marked anemia and jaundice. The patient died of emaciation, dehydration and bronchopenumonia, and an autopsy was performed. Autopsy examination revealed a hen's egg-sized tumor in the tail of the pancreas with metastases in liver, lungs and lymph nodes. In addition, bronchopneumonia and diabetic nephrosclerosis were present. Histologically, the tumor had the characteristics of an islet cell tumor, and histochemically the tumor cells were positive to Grimelius' stain which revealed non-B-islet cell features. Electron-microscopically, the tumor cells had electron dense round membrane-bounded granules resembling non-B-granules of pancreatic islet cells. With the immunoperoxidase procedure (PAP method), tumor cells nearly almost reacted to anti-vasoactive intestinal polypeptide (VIP) serum, which suggested that the tumor of the present case had the capability to produce VIP.