COXSACKIE-B-VIRUS-INFECTION - A POSSIBLE CAUSE OF DERMATOMYOSITIS

Dermatomyositis in a 7 year old girl was diagnosed two months prior to admission to our pediatric rheumatology program. Serological and mole cular biology methods were used to investigate the evidence for a rece nt coxsackie-B-virusinfection. Serum specimens of the patient were ana lysed for detection of coxsackie-B-virus antibodies in a neutralizatio n test (NT), the complement fixation reaction (CF) and for IgM antibod ies in an enzyme-immuno-assay. Muscle biopsy specimens were examined b y means of polymerase chain reaction and in situ hybridisation, using RNA-sequences specific for coxsackie-B-virus. The results in all serol ogical tests were positive, indicating a recent coxsackie-B-virus-infe ction. However, neither polymerase chain reaction nor in situ hybridis ation revealed any persistence of coxsackie-B-virus in the muscle. The results of this study are compatible with published reports. There is strong evidence for a role of coxsackie-B-virus-infection in causing dermatomyositis, but virus persistence in muscle tissue, resulting in chronic inflammation, seems unlikely. Possibly, Coxsackie-B-virus infe ction is implicated in pathogenesis of dermatomyositis by triggering a utoimmune processes in sensitive patients, resulting in chronic inflam mation.