Disseminated Mycobacterium avium Complex Infection in an HIV Patient with a History of Talaromyces marneffei: Diagnostic Value of Blind Subculture and Suspected Management Challenges of Immune Reconstitution Inflammatory Syndrome.

This study reported a 33-year-old male acquired immune deficiency syndrome (AIDS) patient with a 10-year human immunodeficiency virus (HIV) infection history, poor antiretroviral therapy (ART) adherence, and two previous Talaromyces marneffei infections. Self-discontinuation of ART led to severe immunosuppression and disseminated Mycobacterium avium complex (MAC) infection involving the bloodstream and bone marrow. After the restart of ART, the patient developed persistent high fever, which was clinically suspected to be MAC-associated immune reconstitution inflammatory syndrome (IRIS). However, due to the lack of serial HIV viral load and CD4⁺ T lymphocyte data, a definitive diagnosis could not be established. The patient was admitted with fatigue, anorexia, and black stool as the main symptoms. MAC infection was confirmed by blood culture, bone marrow culture, and bone marrow metagenomic next-generation sequencing (mNGS) at a higher-level hospital. Notably, after transfer to our hospital, the microbiology laboratory performed blind subculture on routinely negative blood culture bottles and extended the incubation period to 15 days, successfully isolating MAC. This highlights the crucial significance of close clinical-laboratory collaboration and optimized pathogen detection for diagnosing non-tuberculous mycobacteria (NTM) infections. After initial infection control and ART restart, the patient developed recurrent fever. Given the temporal association with ART reinitiation and the dose-dependent correlation between fever and glucocorticoid adjustments, possible MAC-associated IRIS was suspected. The patient's clinical symptoms improved with glucocorticoid therapy, though this does not confirm the diagnosis. Complications including cytomegalovirus reactivation, adverse drug reactions, and human rhinovirus co-infection were managed in a standardized manner. This case suggests that the diagnosis of disseminated MAC infection in severely immunocompromised AIDS patients relies on efficient collaboration between clinicians and laboratories. However, in the absence of confirmatory immunological and virological evidence, the diagnosis of IRIS remains uncertain. Clinicians should remain vigilant for suspected IRIS when restarting ART while acknowledge that limited data may preclude a definitive diagnosis. Individualized comprehensive strategies covering anti-infection, immunomodulation, anti-inflammation, and supportive treatment are the key to managing such complex HIV-related opportunistic infections.