Definition:
An insulinoma is a tumour of the pancreas derived from the beta cells which while keeping the ability to synthesize and secrete insulin is autonomous of the normal feedback mechanisms.
Diagnosis:
The diagnosis is suspected in a patient with symptomatic fasting hypoglycemia. The conditions of Whipple's triad need to be met for the diagnosis of "true hypoglycemia" to be made: 1) symptoms and signs of hypoglycemia, 2) concomitant plasma glucose level of 45 mg/dL (2.5 mmol/L) or less, and 3) reversibility of symptoms with administration of glucose.
Treatment:
The management is surgical removal of the insulinoma. This may require removing part of the pancreas as well (Whipple procedure and distal pancreatectomy).
Medications such as diazoxide and somatostatin can be used to hinder the release of insulin for patients who are not surgical candidates or who otherwise have inoperable tumours.
Symptoms and Signs:
Patients with insulinomas typically develop neuroglycopenic symptoms. These include recurrent headache, diplopia, lethargy, and blurred vision, particularly with exercise or fasting. Severe hypoglycemia may result in seizures, coma, and eventually, permanent neurological damage. Symptoms arising from the catecholaminergic response to hypoglycemia (i.e. palpitations, tremulousness, tachycardia, sweating, hunger, anxiety, nausea) are not as common. Sudden weight gain (the patient can become massively obese) is occasionally seen.
Causes:
The gene of MEN, an autosomal dominant disease, is known as MEN1 and maps to band 11q13. MEN1 is thought to act as a tumor suppressor gene.
The information on this site is for research purposes only and can not substitute for the advice of a medical professional. Ailments.com is not run by doctors and does not engage in the practice of medicine. Our site is not a medical authority, it is just a research tool for you to use in preparation for consulting with a doctor. We can not guarantee our information is accurate or up to date. Even if a statement made about a medical condition is accurate, it may not apply to you or your symptoms, so you should always consult a doctor. Nothing on our site should be construed as an attempt to offer or render a medical opinion or otherwise engage in the practice of medicine.
