Pancreatic nesidioblastosis in adults.

Nesidioblastosis, a condition characterized by diffuse islet cell hyperplasia arising from the ductal epithelium, is often associated with hyperinsulinemic hypoglycemia. This is a childhood disease and is rarely found in adults. Only 10 histologically proven cases have been recorded, including 3 new cases described in this article. Most clinical and biochemical features are identical to those of an insulinoma, except the proinsulin-like component of circulating immunoreactive insulin, which is usually within the normal range in nesidioblastosis. Limited observations show that some patients may be managed medically with diazoxide. Patients who remain hypoglycemic despite medical therapy require pancreatectomy, although greater than 90% resection frequently results in insulin dependency and permanent diabetes.