Salmonella-triggered reactive arthritis - Use of polymerase chain reaction, immunocytochemical staining, and gas chromatography mass spectrometry in the detection of bacterial components from synovial fluid

Objective. To investigate whether microbial components are present in the c ells of synovial fluid or peripheral blood from patients with Salmonella-tr iggered reactive arthritis (ReA). Methods. Synovial fluid cells and/or peripheral blood cells from 23 patient s with Salmonella-triggered ReA and from 19 control patients with newly dia gnosed rheumatoid arthritis were studied using 3 different polymerase chain reaction (PCR) techniques and immunocytochemical staining. Muramic acid fr om the synovial fluid was studied btv gas chromatography-mass spectrometry, Results. Salmonella chromosomal DNA was not detectable in the synovial flui d cells and peripheral blood leukocytes of patients with Salmonella ReA. In itially, positive reactions were observed in the synovial. fluid cells and peripheral blood leukocytes of 3 of 17 and 3 of 18 patients with ReA respec tively, but in the subsequent PCR studies, these findings were not reproduc ible. Salmonella-specific antigen was detectable by immunofluorescence in t he synovial fluid cells and peripheral blood leukocytes of 4 of 11 and 2 of 7 patients dth ReA, respectively. Muramic acid was present in 2 of 15 syno vial fluid samples from patients with ReA, but the bacterial cultures from synovial fluid were negative. Conclusion. These findings indicate the presence of bacterial degradation p roducts, but not bacterial DNA, in the inflamed joints of patients with Sal monella triggered ReA.