Anti-GAD65, RIA

GAD65 autoantibodies are present in 70-80 % of newly diagnosed patients with type 1 diabetes and can be detected many years before clinical onset of the disease.

The combination of the autoantibodies to GAD65 and IA2 is highly relevant for risk assessment of type 1 diabetes in children and adolescence. These tests in combination are more sensitive and predictive than ICA in risk groups, e.g. relatives of type 1 diabetes. GAD65 autoantibodies also occur in a subset of adults with type 2 diabetes (non-insulin-dependent diabetes mellitus). These patients can have pronounced hyperglycemia, and after therapy with oral hypoglycemic agents for several months to years they may become insulin dependent.

Therefore, these patients are thought to have a slowly progressive form of type 1 diabetes, sometimes called latent diabetes or latent autoimmune diabetes in adults (LADA).

The presence of GAD65 autoantibodies in sera of such patients is a sensitive and specific marker for future insulin dependency.