1. ¹Department and Chair of Rheumatology, Gaetano Pini Institute, University of Milan, Milan, Italy;
2. ²Department of Pathology, Gaetano Pini Institute, Milan, Italy;
3. ³Gastroenterology and Gastrointestinal Endoscopy Service, Department of Internal Medicine;
4. ⁴Gastroenterology Unit, Department of Medical Sciences, IRCCS Maggiore Hospital;
5. ⁵Gastroenterology and Gastrointestinal Endoscopy Unit, Policlinico San Donato, San Donato Milanese, University of Milan, Milan, Italy

Correspondence: Prof. Maurizio Vecchi, Gastroenterology and Gastrointestinal Endoscopy Unit, Policlinico San Donato, Via Morandi 30 20090 San Donato Milanese (MI) Italy

Received 17 December 2005; Revised  0000; Accepted 9 September 2005.

Abstract

Pancreatic polypeptide (PP) islet cell tumors are usually not associated with a distinct clinical syndrome, although some reports suggest that they can cause a watery diarrhea syndrome similar to vasoactive intestinal polypeptide (VIP) cell tumors.

We report the case of a young woman with an unusual presentation of a pancreatic neuroendocrine tumor mainly secreting PP. The patient developed a reversible hypokalemic rhabdomyolysis very likely secondary to the presence of the tumor. The myopathy resolved following the restoration of normokaliemia using potassium supplementation and a partial laparoscopic pancreasectomy.

Isolated cases of hypokalemic rhabdomyolysis induced by intestinal diseases have been described in literature but these did not include gastroenteropancreatic neoplasms. We suggest that pancreatic neuroendocrine tumors should be added to the list of intestinal diseases capable of producing hypokalemic myopathy.