Antiphospholipid-Syndrom 2007

[Laboratory diagnostics for early detection of rheumatic autoimmune diseases: a guide for the general practitioner]

Autoimmune diseases are a clinically heterogeneous group of disorders that represent a challenge for the general practitioner in daily routine. Except for rheumatoid arthritis, which is one of the most frequent autoimmune diseases with a prevalence of approximately 1 % of the population, systemic autoimmune disorders are rare. Thus outside specialized wards it might be a challenge to diagnose the underlying autoimmune disease considering the often kaleidoscopic clinical manifestations. Together with careful anamnesis and suspicious clinical symptoms determination of specific autoantibodies can support the suspected diagnosis. The Austrian group of the European autoimmune standardization initiative (EASI) firstly published this guide 2009 with the aim to provide a map through the jungle of the biomarkers for autoimmune diseases for the general practitioner.

[Diagnostic use of autoantibodies]

In the field of dermatology, autoantibody diagnostics are relevant in bullous autoimmune and connective tissue diseases and in certain forms of systemic vasculopathy and psoriatic arthritis. Autoantibody diagnosis of bullous autoimmune skin diseases is an area of dermatology, while serodiagnosis of the other diseases is also performed in rheumatology or in large laboratory centers. Antibody diagnosis of bullous skin diseases is more targeted, as the localization, molecular structures, and function of the relevant epidermal or dermal autoantigens are now known to a large extent, and there are sound experimental indications of the pathogenetic role of these autoantibodies. In practical terms, it is important that some of these antibodies are not only used for the initial diagnosis but also to evaluate the course of the disease and the success of treatment. The autoantibody profile in patients with connective tissue disease may also be disease specific, whereas the pathogenetic significance of these autoantibodies, which are usually directed against nuclear and cytoplasmic components or membrane receptors, is still largely unknown. Autoantibody diagnosis is also important in practice in certain vascular diseases. The future will show whether the determination of antibodies against cyclic citrullinated peptides will become more important in diagnosing and following the course of psoriatic arthritis in practice.