title: Chlamydia trachomatis in reactive arthritis.
abstract: Evidence of deposition of chlamydial antigen in the joint was sought in 10 patients (9 of them male) with classic sexually acquired reactive arthritis, 15 women with unclassified seronegative oligoarthritis involving the knee and 15 individuals with established rheumatic disorders not associated with genital-tract or other infections. Using a fluorosceinated monoclonal antibody to the major outer membrane protein of Chlamydia trachomatis (MicroTrak, Syva) in a direct immunofluorescence test, particulate antigen with physical characteristics of chlamydial elementary bodies was seen in synovial fluid cell smears or synovial biopsies, or both, from 6, 5, and 0 patients, respectively. No typical chlamydial intracellular inclusions were seen. Corroborative evidence of recent chlamydial infection was provided by the finding of high titres of serum chlamydial antibody in all antigen-positive patients with sexually acquired reactive arthritis, including 3 from whom a genital-tract isolate was obtained, and 3 of the 5 women with unclassified arthritis. It is postulated that Chlamydia trachomatis organisms reach the joint during acute genital-tract infection, and the processing and presentation by class I major histocompatibility determinants of chlamydial antigens is a critical step in the initiation of reactive arthritis in some patients.
authors.affiliation: Department of Rheumatology, Westminster Hospital, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Keat
authors.forename: B
authors.initials: B
authors.lastname: Thomas
authors.forename: R
authors.initials: R
authors.lastname: Hughes
authors.forename: D
authors.initials: D
authors.lastname: Taylor-Robinson
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000276:immunology*; D001170:Arthritis, Infectious / Q000209:etiology / Q000276:immunology* / Q000382:microbiology; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology; D002690:Chlamydia Infections / Q000276:immunology; D002692:Chlamydia trachomatis / Q000276:immunology* / Q000302:isolation & purification; D005260:Female; D005835:Genitalia / Q000382:microbiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015231:Sexually Transmitted Diseases, Bacterial / Q000150:complications / Q000382:microbiology; D013582:Synovial Fluid / Q000276:immunology / Q000382:microbiology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins