Atypical mycobacteriosis in two patients with rheumatoid arthritis.

Abstract We report two cases of rheumatoid arthritis (RA) with atypical mycobacteriosis. Opportunistic infections are critical complications for rheumatic diseases. The use of steroids or immunosuppressants may increase the risk of opportunistic infections. However, these reports are rare in that they demonstrate atypical mycobacterial infections as complications of RA, even though no immunosuppressive agents were used. We discuss the characteristics of atypical mycobacterial infections of the lung in RA.