Anti-interferon-γ autoantibody and opportunistic infections: case series and review of the literature

Immune defects in interleukin-12-dependent interferon-gamma (IFN-γ) pathways are associated with disseminated infections caused by non-tuberculous mycobacteria (NTM) and Salmonella. Recently, there have been an increasing number of reports of acquired autoantibodies to IFN-γ in adults, especially in Asian patients. We describe here three human immunodeficiency virus-negative Thai adults who had persistent or recurrent disseminated infections caused by NTM, Salmonella, and other opportunistic pathogens, possibly due to anti-IFN-γ autoantibodies. The antibodies were shown to exhibit very high inhibitory activity to IFN-γ. Two patients also developed Sweet’s syndrome during the course of infections. In addition, we also review all previous reports of patients with anti-IFN-γ antibodies who were susceptible to NTM and Salmonella infections.