Opportunistic infections result from infections caused by bacteria, mycobacteria, viruses, fungi, protozoa, or helminths, potentially leading to severe disease and death. These infections are a significant cause of morbidity and mortality among individuals with profound immunosuppression, such as people living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) (PLWHA) and solid organ transplant recipients. Mycobacterial infections, including those caused by Mycobacterium tuberculosis and nontuberculous mycobacteria (NTM), particularly the Mycobacterium avium complex (MAC), are responsible for potentially severe and disseminated disease. In this article, we report three cases from a public teaching hospital in the state of São Paulo, Brazil, involving the evaluation of PLWHA presenting with nonspecific gastrointestinal symptoms and the diagnostic workup for gastrointestinal tract (GIT) mycobacterial infection, with a focus on endoscopic imaging findings and their different patterns of involvement.
Vanin et al. (2026) studied this question.