Microbiology of acute arthropathies among children in Argentina: II. Chlamydia trachomatis and pneumoniae

No analysis has been carried out on the impact of Chlamydia in pediatric patients with arthritis. The present study was conducted to investigate whether Chlamydia trachomatis and Chlamydia pneumoniae could be identified as a triggering infection in 33 pediatric patients including adolescents with acute joint disorders by using an extensive laboratory approach. Synovial fluid, nasopharyngeal secretion, and urethral swab samples were screened for the presence of Chlamydia by culture, enzyme immunoanalysis and immunofluorescence assay. In addition, in synovial fluid samples, detection of Chlamydia trachomatis and pneumoniae DNA was performed by nested-PCR. Specie-specific antibodies were tested in sera by microimmunofluorescence method. Of the 33 patients, 3 (9%) had joint disorders associated with Chlamydia. In synovial fluid samples of 2 (6%) patients with evidence of reactive arthritis we found C. trachomatis antigens and specific nucleic acids. The presence of this organism and its antigenic components was also confirmed in urethral swabs from these patients. C. pneumoniae DNA and antigens were found in joint fluid from one patient (3%) who presented inflammatory arthritis and respiratory infection. Bacterial isolation and antigenic detection gave positive result in nasopharyngeal secretion from this patient. Antibody titers against C. trachomatis or C. pneumoniae were observed in paired sera from these 3 patients showing evidence of preceding infection. We conclude that the diagnosis of Chlamydia-associated arthritis was based on the clinical picture, finding of the bacteria, nucleic acids and/or its antigens at the site of inflammation and relevant exclusion of other triggering microbes. Our study represents the first data from Argentina linking Chlamydial infection to joint disorders in children and adolescents and may contribute to early diagnosis to prevent the evolution to more advanced clinical forms.