Absence of Mycobacterium tuberculosis DNA in synovial fluid from patients with rheumatoid arthritis

Infection with Mycobacterium (M.) tuberculosis may not be responsible for the development of rheumatoid arthritis (RA). Studies in laboratory animals have suggested that M. tuberculosis may be involved in the development of arthritis. Researchers used the polymerase chain reaction to analyse synovial fluid samples from 31 RA patients and 13 control patients. PCR did not detect the DNA of M. tuberculosis in the cellular components of the synovial fluid samples from RA patients. The study did not rule out the possibility that M. tuberculosis DNA might be found in synovial membranes rather than synovial fluid. Nor did the study rule out the possibility that M. tuberculosis might trigger RA in genetically or otherwise predisposed patients.