TY - JOUR T1 - Immunological basis of chlamydia induced reactive arthritis JF - Sexually Transmitted Infections JO - Sex Transm Infect SP - 156 LP - 161 DO - 10.1136/sti.76.3.156 VL - 76 IS - 3 AU - J S H Gaston Y1 - 2000/06/01 UR - http://sti.bmj.com/content/76/3/156.abstract N2 - A small proportion of patients who present with clinical symptoms of urethritis or cervicitis later develop inflammatory arthritis and, for an unfortunate minority, this can be the beginning of a persistent and disabling disease. This illness is now termed reactive arthritis,1 rather than the older term, Reiter's disease. Reiter described a triad of urethritis, conjunctivitis, and arthritis in first world war soldiers in the trenches following attacks of dysentery, and mistakenly believed that it was due to infection with a novel spirochaete. However, others had previously described the same syndrome, and the triad has no specific pathological significance; patients can have the same arthritis whether they have conjunctivitis or not, and urethritis is not infrequently absent, particularly in cases triggered by gut infection. Because of the emphasis on urethritis in the definition of Reiter's disease, it has often been assumed subsequently that Reiter's disease is synonymous with sexually acquired reactive arthritis (SARA),2 whereas in Reiter's report the index cases followed gut infection. For all these reasons the term reactive arthritis is to be preferred and avoids unnecessary categories such as “incomplete” Reiter's disease. There are many advantages, from a rheumatological view, in studying the pathogenesis of reactive arthritis. Unlike, for instance, rheumatoid arthritis, the onset is sharply defined rather than insidious, and is the result of an identifiable antigenic challenge (in the form of an infectious organism) to the host immune system. It has also been clear for some time that host factors influence who develops arthritis, HLA-B27 being the best described of these, and that the same factors play a part in the whole family of arthritic conditions which make up the seronegative spondyloarthropathies (table 1). There is, therefore, an expectation that exploration of the host:pathogen interaction in reactive arthritis may provide valuable insights into the pathogenesis … ER -