The prevalence of Mycoplasma fermentans in patients with inflammatory arthritides

OBJECTIVES: To search for evidence that Mycoplasma fermentans is involved in the pathogenesis of some forms of human arthritis by testing for the presence of mycoplasmal DNA in joint material. METHODS: M. fermentans DNA was detected by the identification of a 104-base pair amplification product of the polymerase chain reaction (PCR). RESULTS: M. fermentans DNA was detected in synovial fluid samples from six (17%) of 35 patients with rheumatoid arthritis (RA) and 18 (21%) of 85 patients with seronegative arthritis. These detection rates were significantly greater than in samples from patients with osteoarthritis or crystal synovitis, none of 26 of these being positive. CONCLUSIONS: M. fermentans could be involved in the pathogenesis of some forms of inflammatory arthritis and this possibility is worthy of further study.