Disseminated Mycobacterium haemophilum skeletal disease in a patient with interferon-gamma deficiency.

Disseminated non-tuberculous mycobacterial (NTM) infection is rare in immunocompetent adults. Anti-interferon-gamma (IFN-γ) autoantibodies have recently been associated with NTM infections, particularly in patients of Asian ethnicity. We describe a case of disseminated Mycobacterium haemophilum skeletal infection due to anti IFN-γ autoantibodies in a 71-year-old Cambodian man. He responded to a combination of anti-mycobacterial antibiotics without requirement for immunomodulator therapy. Testing for acquired IFN-γ deficiency due to IFN-γ autoantibodies should be considered when standard tests for immunodeficiency are negative in patients with unusual or severe opportunistic infections, including NTM.