Iaa

Antibodies against insulin(IAA) can develop as a result of insulin therapy with exogenous insulin or in the context of autoimmunological diabetes mellitus (type 1 diabetes). IAA occur in direct dependence on age in up to 90% of patients. The younger the patients are at the time of manifestation of type 1 diabetes, the more likely it is that IAA will be detected.

Important: Insulin antibodies are usually the first autoantibodies to be detected and can often be detected several years before the clinical manifestation of type 1 diabetes mellitus. Thus, they play an important role in the risk assessment of the development of diabetes in young children.

IA-2-Ak are directed against an islet cell membrane protein (ICA512, tyrosine phosphatase IA-2). At 60-80%, IA-2-Ak are slightly less frequently positive for type 1 diabetes than islet cell or GAD65 antibodies. In first diabetic patients, IA-2 antibodies are positive in 60-70% of type 1 diabetics and in 2-5% of first-degree relatives. Of these antibody carriers, 65% develop diabetes mellitus within 5 years.

The detection of IA2 antibody is performed by an enzyme linked immunosorbent assay (ELISA) using recombinant human tyrosine phosphatase (IA2) for its quantitative and qualitative determination.

Sample volume: > 75 µL serum

Reference range: < 10 IU/ml

Material: 1 ml serum

The determination of insulin Ac is not advisable under insulin therapy, as it is not possible to differentiate between induced insulin antibodies and autoimmune insulin Ac.

Prevalences at initial diagnosis: 100 % (children < 5 years); 90 % (children/adolescents < 17 years); < 20 % (adults > 17 years). Several studies have shown that the occurrence of IAA can reduce the risk of diabetes in relatives1 . In several studies it was shown that the occurrence of IAA significantly increased the risk of diabetes in relatives1. degree of diabetics: 37% of the persons with both antibodies (IAA positive/ICA positive) developed a manifest type 1 diabetes within the follow-up, in contrast to 14% (ICA positive/IAA negative) and 16% (ICA negative/IAA positive) with only one positive autoantibody.