[Diagnosis and therapy of chronic polyarthritis]

Rheumatoid arthritis (RA) is the most frequent inflammatory joint disease, and it affects about 1% of the population. The onset of arthritis is rarely acute; it is subacute and usually progresses slowly. The clinical picture of RA is variable: mild to very aggressive and destructive courses, sometimes accompanied by organ involvement, leading to severe functional impairment and early disability can be observed. RA is diagnosed according to the ACR criteria published in 1958 and modified in 1988. The appearance of a palpable joint swelling or effusion is obligatory for the clinical diagnosis of arthritis. In RA, typically involvement of the joint of the hands and feet can be seen. Laboratory parameters play an important role as both diagnostic and prognostic tools. Besides clinical features and laboratory parameters, imaging techniques provide another cornerstone in the diagnosis of RA. Until now plain X-rays, which primarily visualize osseous changes, are the most important technique in daily practice, whereas magnetic resonance imaging and ultrasound may provide information about soft tissue changes in an earlier stage of disease. The main differential diagnoses of RA to be considered are the seronegative spondylarthropathies (psoriatic arthritis, arthritides accompanying inflammatory bowel diseases, Reiter's syndrome, and spondylitis ankylosans with peripheral arthritis), Parvovirus-induced arthritis, crystal-induced arthritides and septic arthritis. Early diagnosis and therapeutic intervention seem to be of great prognostic importance. In several independently performed investigations a higher mortality was found in RA patients than in the normal population. Drug therapy of RA consists of nonsteroidal antirheumatic drugs (NSAIDs), corticosteroids and disease-modifying drugs (DMARDs). When the functional and radiological parameters were assessed, the DMARDs were found to have a disease modifying and in rare cases a remission-inducing property. Moreover, tolerance these to drugs is limited. Newer therapeutic trials have employed substances like Tenidap, Leflunomid, bacterial extracts, antibiotics and biological subcomes (e.g., monoclonal antibodies against cytokines, fusion proteins for soluble cytokinereceptors). Some promising results of these investigations need confirmation in larger patient populations, but some new perspectives for a more efficacious treatment of RA can be expected.