[Reactive arthritis caused by Yersinia in children. Report of 4 cases]

Among a group of children hospitalized for "joint pain", four of the cases of reactive arthritis were due to Yersinia infection. These four cases are described. Some patients had suggestive clinical symptoms but serologic studies were needed to establish the diagnosis. Tissue group studies showed that two children were HLA B27 and one was HLA B7. Reactive arthritis due to Yersinia in a form of "enteral arthritis". The prevalence of Yersinia arthritis has not been documented. Serologic tests are essential to outrule the main differential diagnosis, i.e. chronic juvenile arthritis (juvenile rheumatoid arthritis). Short-term resolution of symptoms is seen in every case. The long-term outcome is less well documented, especially with regard to the risk of recurrence and to relationships with peripheral joint disease and spondylarthropathies of early adulthood. HLA B27 positivity may be a risk factor. The pathogenesis of Yersinia-induced reactive arthritis is unclear; current studies are focusing on immunologic factors. The uncertainties concerning long-term outcome justifies renewed interest in childhood reactive arthritis.