title: Hyperinsulinemic hypoglycemia due to diffuse nesidioblastosis in adults: a case report.
abstract: Persistent hyperinsulinemic hypoglycemia is caused most commonly by an insulinoma in adults or by nesidioblastosis in neonates. In adults, nesidioblastosis is a rare disorder characterized by diffuse or disseminated proliferation of islet cells. We recently encountered a case of nesidioblastosis in an adult. A 71-year-old man was admitted due to intermittent general weakness, abdominal pain, and mild dyspnea. The patient underwent a subtotal gastrectomy for a gastric adenocarcinoma two years ago. After 5 d of admission, the patient showed symptoms of cold sweating, chilling, and hypotension 30 min after eating. Thereafter, he frequently showed similar symptoms accounting for hypoglycemia regardless of food consumption. Laboratory findings revealed a low fasting blood glucose level (25 mg/dL), and a high insulin level (47 muIU/mL). Selective intra-arterial calcium stimulation with hepatic venous sampling (ASVS) was performed to localize a mass and revealed an increased insulin level about four-fold that of the normal fasting level at 60 s in the splenic artery, which suggested the presence of an insulinoma in the tail of pancreas. A distal pancreatectomy was performed. Neither intraoperative exploration nor a frozen biopsy specimen detected any mass-forming lesion. On the histological examination, many of the islets were enlarged and irregularly shaped in all specimens, the arrangement of which was a lobulated islet pattern. Cytologically, a considerable subpopulation of endocrine cells showed enlarged and hyperchromatic nuclei. By immunohistochemistry, the cells were identified as beta-cells. These clinical, radiological, microscopic and immuno-histochemical findings are consistent with diffuse nesidioblastosis in adults.
authors.affiliation: Department of Pathology, Chosun University Hospital, 588, Seosuk-dong, Dong-gu, Gwangju, Korea.
authors.forename: Ran
authors.initials: R
authors.lastname: Hong
authors.forename: Dong-Youl
authors.initials: DY
authors.lastname: Choi
authors.forename: Sung-Chul
authors.initials: SC
authors.lastname: Lim
mesh_terms: D000368:Aged; D006801:Humans; D006946:Hyperinsulinism / Q000209:etiology*; D007003:Hypoglycemia / Q000209:etiology*; D007515:Islets of Langerhans / Q000473:pathology / Q000601:surgery; D008297:Male; D046768:Nesidioblastosis / Q000150:complications* / Q000473:pathology / Q000601:surgery; D010180:Pancreatectomy