IA2 antibody testing is used in the differential diagnosis of type 1 diabetes mellitus from type 2 diabetes, in identifying individuals at risk for type 1 diabetes (including relatives of patients with diabetes), and in predicting the need for insulin therapy in patients with adult-onset diabetes.
Autoantibodies to pancreatic islet cells are known to be associated with type 1 diabetes mellitus. In recent years, several autoantigens have been identified against which islet cells antibodies are directed. These include islet antigen 2 (IA2) associated with tyrosine phosphatase, glutamic acid decarboxylase 65 (GAD65), the zinc transporter ZnT8, and insulin. One or more of these autoantibodies are detected in 96% of patients with type 1 diabetes and are detectable before the onset of clinical symptoms, as well as in symptomatic individuals.
IA2 antibodies have a sensitivity of 57% and a specificity of 99% for the laboratory diagnosis of type 1 diabetes. Autoantibodies in patients who are going to develop type 1 diabetes are usually detectable before the age of 3 years. Some patients with type 1 diabetes are initially diagnosed with type 2 diabetes because of the onset of symptoms in adulthood, obesity, and early insulin independence. These patients with latent autoimmune diabetes can be distinguished from patients with type 2 diabetes by the detection of one or more autoantibodies to pancreatic islets (including IA-2).
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.