[Laboratory diagnosis of rheumatic diseases. Part 3: arthritides caused by infection].

This third part of this series of articles on laboratory diagnostics of rheumatic diseases considers the rheumatic diseases caused by infection by microorganisms, or reactive arthritides. The basis for laboratory diagnostics of infection-reactive arthritides is the investigation of anti-infection antibodies. In some situations, DNA amplification methods may be helpful.

Disappearance of specific immune response after successful therapy of chronic Lyme borreliosis.

512 consecutive patients suffering from chronic Lyme borreliosis have been treated according to a standardized therapy regimen which was developed using the results of a controlled trial (Hassler et al., 1990; Hassler, 1992). Follow up was performed for at least 6 (maximum 16) years.

Autoantibody profiles in the sera of European patients with myositis.

Objective: To determine the prevalence of myositis specific autoantibodies (MSAs) and several myositis associated autoantibodies (MAAs) in a large group of patients with myositis.

Methods: A total of 417 patients with myositis from 11 European countries (198 patients with polymyositis (PM), 181 with dermatomyositis (DM), and 38 with inclusion body myositis (IBM)) were serologically analysed by immunoblot, enzyme linked immunosorbent assay (ELISA) and/or immunoprecipitation.

Results: Autoantibodies were found in 232 sera (56%), including 157 samples (38%) which contained MSAs.

[A high rheumatoid factor titer caused by vaccination?].

A forty year old healthy adult man was admitted to our outpatient department because of a highly elevated rheumatoid factor. Since the person was planning an extended stay in Africa, we performed an extensive history, clinical and laboratory examination to rule out oligosymptomatic inflammatory diseases. We further analyzed if the person presented genetic risk factors to develop rheumatic diseases in the future or if the presence of the rheumatoid factor could be a reaction to multiple immunizations.

Tick-borne encephalitis in the Saarland and the Rhineland-Palatinate.

The Saarland and the Rhineland-Palatinate are not considered endemic regions for tick-borne encephalitis (TBE), and patients in this region have not been routinely advised to undergo vaccination or serologic testing for TBE. In 1994, a significantly increased incidence of TBE cases was noted in the neighbouring state of Baden-Württemberg. In the same year, the first TBE acquired in the Saarland was diagnosed.