[Adult-onset immunodeficiency induced by anti-interferon-γ autoantibodies: report of 13 cases].

To investigate the clinical characteristics of a group of patients with adult-onset immunodeficiency (AOID) induced by anti-interferon-γ autoantibodies (AIGA). Thirteen cases of AOID in a northern China medical center (Peking Union Medical College Hospital) from October 2020 to April 2022 were included. Data comprising clinical manifestations, laboratory results, infection sites and pathogens were collected. Among the 13 patients, 5 were male. The median age of disease onset was 47 (14 to 71) years. The median time from symptom onset to diagnosis was 4 years (1 to 8 years). Four patients were from northern China, and 9 from southern China. Common symptoms included lymphadenopathy (13/13), fever (12/13), respiratory tract symptoms (12/13), and weight loss (11/13). Laboratory tests showed increased levels of white blood cell count (9/13), neutrophil count and proportion (9/13), erythrocyte sedimentation rate (ESR) (12/13), and C reactive protein (CRP) (11/13). The median plasma titers of AIGA upon diagnosis were 5681(3194, 13246). Sites of infection included lungs (12/13), lymph nodes (9/13), bones and joints (9/13), skin and soft tissue (7/13), blood flow and bone marrow (4/13), and glands (3/13). Most patients had nontuberculous mycobacteria (NTM) (12/13) infection. Seven patients had more than one pathogen. AOID also affects patients visiting northern China hospitals. AIGA screening is recommended among patients with disseminated NTM infections or recurrent infections.