Molecular diagnosis of Ureaplasma urealyticum in an immunocompetent patient with destructive reactive polyarthritis.

Polymerase chain reaction (PCR) amplification, which is a useful method for detecting infectious agents in joints, has potential utility in the molecular diagnosis of venereal-associated arthritis. Among pathogens detected by this technique, Ureaplasma urealyticum, which is primarily associated with reactive arthritis (ReA), is also implicated in septic arthritis in immunocompromised patients. We report here a case of destructive polyarthritis, initially suggestive of septic arthritis, in an immunocompetent patient whose PCR positivity for U. urealyticum DNA in one joint, in conjunction with the disease outcome and histologic findings, led to the diagnosis of destructive ReA.