Autoimmune Hypoglycaemia

Abstract

Insulin autoimmune syndrome and type B insulin resistance are rare causes of autoimmune hypoglycaemia. Insulin autoimmune syndrome is due to autoantibodies against endogenous insulin, and typically presents with episodes of postprandial hyperinsulinaemic hypoglycaemia. Type B insulin resistance is caused by autoantibodies against the insulin receptor, and may present with severe insulin resistance and hyperglycaemia, hypoglycaemia following a period of hyperglycaemia, or hypoglycaemia alone. The combination of clinical manifestations and positive insulin or insulin-receptor antibodies in the blood confirm the diagnosis of autoimmune hypoglycaemia. However, in rare cases, insulin treatment in patients with positive insulin antibodies and frequent episodes of hypoglycaemia can complicate the diagnosis of insulin autoimmune syndrome. In this chapter, the clinical characteristics, pathophysiology, diagnosis, and management of autoimmune hypoglycaemia syndromes will be described, and the challenges in identifying those insulin antibodies which may significantly affect insulin kinetics in insulin-treated diabetes discussed.