Pulmonary Mycobacterium avium Infection in a Patient with Crohn's Disease under Azathioprine Treatment

Anti-tumor necrosis factor alpha therapy is known as a risk factor of non-tuberculous mycobacteria (NTM) infection. However, there are few reports of NTM infection under treatment with thiopurine agents. We herein report a first case of pulmonary infection caused by Mycobacterium avium complex (MAC) in a patient with Crohn's disease under treatment with thiopurine. After starting antibiotics therapy for NTM including clarithromycin, rifampicin, ethambutol and streptomycin, MAC infection was well controlled, and she kept clinical remission even without azathioprine. In conclusion, our case emphasizes the importance of considering NTM infection in respiratory complications of inflammatory bowel disease patients under immunosuppressive therapies.