Rabson-Mendenhall Syndrome is rare syndrome of extreme insulin resistance. It is characterized by severe insulin resistance leading to postprandial hyperglycemia and fasting hypoglycemia. The onset of the disease is very early, with affected patients experiencing intrauterine and postnatal growth retardation. They suffer from pineal hyperplasia, impaired linear growth, fat and muscle tissue hypoplasia, abnormal dentition, and ectodermal tissue overgrowth.
Diagnosis of the condition is based on the findings of fasting hypoglycemia, postprandial hyperglycemia, and hyperinsulinemia. Differential diagnoses include the more severe Donohue Syndrome and the clinically less severe type A insulin resistance diabetes mellitus with acanthosis nigricans (Iran Type A). Treatment is usually with high doses of insulin and/or recombinant IGF1. Most patients tend to die before reaching their 30s due to diabetic ketoacidosis.