Deepening Understanding of the Clinical Features and Diagnostic Approaches to Anti-Interferon-Gamma Autoantibody Associated Adult-Onset Immunodeficiency in the Last 20 Years: A Case Report and Literature Review.

Anti-interferon-gamma autoantibody (AIGA)-associated adult-onset immunodeficiency (AOID) is an emerging disease that can lead to serious opportunistic infections, which has a history of 20 years since it was first reported in 2004. It's a hard-detected AOID caused by AIGA. In recent years, there has been an increasing number of reports on the disease, but there is still a lack of consensus on the diagnosis and treatment. We here report a case of a 70-year-old Chinese male who had had AIGA in serum and suffered from recurrent pyothorax. Although his condition improved with antimicrobial therapy each time, his pyothorax frequently relapsed, requiring repeated hospitalizations. A literature review of AIGA-associated AOID was conducted. We searched PubMed, Web of Science, Embase, and the Chinese literature database for manuscripts concerning AIGA. Cases detected with AIGA and met our criteria were included. A total of 502 patients were retrospectively analyzed, with 256 (51.0%) males and 246 (49.0%) females. The majority of patients are from Southeast Asia (98.2%). Lymph node (83.7%) is the most commonly involved organ, followed by the lung (60.6%). Nontuberculous mycobacteria (NTM) was identified as the predominant pathogen reported in 77.49% of the patients. The clinical manifestations are diverse and non-specific for the disease often presenting with multi-organ involvement and multiple infections. Timely identification of patients with AIGA, appropriate diagnosis, and individualized treatment are critical; thus, we propose a reasonable diagnostic criterion and a structured diagnostic and treatment process based on our findings to provide clinicians with comprehensive information for clinical practice.