Less than 10% of patients with MEN type I have an insulinoma, and less than 10% of patients with insulinomas have MEN type I.20,21 The median age of onset is in the third decade. There is a 1 to 1 male-to-female ratio. In MEN type I, approximately 80% are associated with multifocal islet disease.22 Although the insulin-producing tumor may be one of several islet cell tumors in the patient, the tumor that is making the insulin is usually solitary and relatively large, on the order of 2 to 4 cm. Patients usually present with symptoms of neuroglycopenia during fasting hypoglycemia (< 40 mg/dL). The diagnosis is made by documenting hypoglycemia in association with inappropriately increased plasma levels of insulin and C peptide during a prolonged fast. Other causes of hypoglycemia include medications (insulin, sul-fonylureas), liver dysfunction, renal failure, wasting, and growth hormone (GH) deficiency. Once a diagnosis is made, preparations for surgical approach by preoperative localization are necessary. Computed tomography (CT), ultrasonogra-phy, and somatostatin receptor scintigraphy (SRS) are currently our standards for preoperative localization. The studies are designed not only to identify the insulin-producing tumor but also to identify other sites of disease. The imaging studies, however, tend to underestimate the number of lesions in patients with MEN type I. In occasional patients, selective angiography with calcium provocation of insulin production and measurement in the hepatic veins is useful to definitely regionalize the insulin-producing tumor.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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