Abstract
BACKGROUND: Anti-interferon-γ autoantibodies (AIGAs) are associated with adult-onset immunodeficiency syndrome, which makes individuals susceptible to intracellular pathogen infections. However, AIGAs are rarely reported in adolescents. CASE PRESENTATION: We report a 13-year-old Chinese boy who presented with fever, cough, and enlarged cervical lymph nodes. Blood cultures yielded Mycobacterium abscessus, and Talaromyces marneffei (TM) was cultured from pericardial effusion. Whole exome sequencing revealed no pathogenic variants. Notably, high levels of neutralizing AIGAs were detected in the patient's serum. After receiving treatment for Mycobacterium abscessus and antifungal therapy for TM, the patient showed significant improvement. However, at the 19-month follow-up, the patient developed a Mycobacterium asiaticum infection. CONCLUSION: This case highlights the importance of screening for AIGAs in pediatric patients with disseminated TM or NTM infections. Prolonged treatment and continuous follow-up remains crucial for managing pediatric patients with AIGAs.