ABSTRACT
The study was performed on 40 reactive arthritis patients and 20 healthy controls. Clinical and laboratory evaluation was used to elaborate the bacterial antigens role in the pathogenesis of reactive, arthritis. Serum samples were collected for rheumatoid factor, tissue typing and Widal test. Stool samples were collected for culture. Urogenital swabs were taken for culture and polymerase chain reaction [PCR] for chlamydia-DNA. There was preceding infection of the urogenital tract through positive urogenital swab cultures of mycoplasma in 8 patients [20%], positive PCR for chlamydia-DNA in 19 patients [47.5%] and previous gastro-intestinal infection through positive compylobacter culture in 10 patients [25%], shigella in 5 patients [12.5%] and salmonella in 10 patients [25%]. There was some patients had combined infection with different types of organism. There was a role of bacterial antigens in the pathogenesis of reactive arthritis, which affect gastero-intestinal tract such as salmonella and urogenital tract such as chlamydia trachomatis