Overview:
Islet autoantibodies are proteins produced by the immune system that has been shown to be associated with Type 1 diabetes. Testing can detect the presence of one or more of these autoantibodies in the blood.
Type 1 diabetes is a condition characterized by a lack of insulin due to autoimmune processes that destroy the insulin-producing beta cells in the pancreas. Islet autoantibodies can be present prior to the diagnosis of type-1 diabetes, are usually present at the time of the diagnosis, and decrease in frequency over 5 to 10 years following the diagnosis of Type 1 diabetes.
Islet autoantibodies are markers of autoimmune (self-reactive) response to islets, but islet autoantibodies do not cause Type 1 diabetes.
Interpretations:
If ICA, GADA, IA-2A, and ZnT8A are present in a person with symptoms of diabetes, the diagnosis of type 1 diabetes is confirmed. Likewise, if IAA is present in a child with diabetes who is not insulin-treated, type-1 diabetes is the likely cause of diabetes.
If no islet autoantibodies are present onset or within a few years of diagnosis, then it is unlikely that the diabetes is type-1. Some people who have type-1 diabetes will never develop delectable of islet autoantibodies, but this is rare. The majority of people, 95% or more, with new-onset type 1 diabetes will have at least one islet autoantibody.
To identify people at increased risk of developing type 1 diabetes or requiring insulin treatment; to aid in the classification of diabetes.