Chlamydia and associated arthritis

An inflammatory arthritis is known to follow urogenital infection with the intracellular bacterium Chlamydia trachomatis in some individuals, and rece nt research results have elucidated important aspects of the characteristic s of this Chlamydia-associated joint disease. Although the several extra-ar ticular features of Chlamydia-induced arthritis have been defined clinicall y, their detailed causes remain largely unexplained. Current data indicate that the clinical characteristics of joint disease associated with C, trach omatis infection and those associated with postenteric arthritis are not ea sily distinguishable, although the response of each to antibiotic therapy d oes differ. The biologic characteristics of Chlamydia and enteric organisms in the joint show profound differences, and these are probably responsible for the variable responses to drug treatment. Molecular analyses of synovi al C. trachomatis have demonstrated that long-term infection of the joint o ccurs primarily in synovial tissue and that the organism exhibits highly un usual biologic properties in its synovial context. These unusual molecular, biochemical, and other characteristics provide explanations for the freque nt culture negativity of joint materials for C. trachomatis and for several other aspects of the arthritogenic process. Much remains to be learned con cerning the behavior of this organism in the joint and concerning its inter action with its synovial host cells. (C) 2000 Lippincott Williams & Wilkins , Inc.