Mycobacterium other than tuberculosis (MOTT) infection: an emerging disease in infliximab-treated patients.

Objectives: Infliximab has revolutionized treatment of rheumatologic diseases and inflammatory bowel disease. However, it increases the risk of tuberculosis. Less is known about the development of Mycobacterium other than tuberculosis (MOTT) infection. We review the literature on non-tuberculous mycobacterial infections in infliximab-treated patients and report the first case of disseminated Mycobacterium avium complex in an infliximab-treated patient complicated by immune reconstitution inflammatory syndrome.

Methods And Results: MEDLINE search with the keywords mycobacteria and infliximab revealed four cases of MOTT in patients treated with infliximab: fatal Mycobacterium peregrinum pneumonia in a patient with polymyositis and dermatomyositis; a patient with rheumatoid arthritis with skin and soft tissue infection with Mycobacterium abscessus; Mycobacterium fortuitum in a patient with rheumatoid arthritis; and a case of pulmonary MAC without dissemination. Review of US data from 1998 to 2002 published by Wallis et al. revealed that out of more than 233,000 patients treated with infliximab, 30 developed unspecified mycobacterial species infection. No further data was available regarding these cases.

Conclusion: MOTT infection is a rare but emerging complication of infliximab therapy. MOTT cases tend to progress rapidly in infliximab-treated patients and withdrawal of infliximab therapy can result in immune reconstitution.