Acquired immunodeficiency syndrome-related progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome: prevalence, main characteristics, and outcomes in a Brazilian center

Background Progressive multifocal leukoencephalopathy (PML) - immune reconstitution inflammatory syndrome (IRIS) in people living with HIV/AIDS (PLWHA) has been rarely described in low- and middle-income countries. Objective To describe the prevalence of PML-IRIS among PLWHA with PML and its main features in a tertiary hospital in Brazil. Methods We performed a retrospective cohort study. We included PLWHA with PML-IRIS patients admitted at Instituto de Infectologia Emílio Ribas , São Paulo, Brazil, between 2011 and 2021. We retrieved information on neurological manifestations, neuroimaging findings, treatments, and outcomes. Results We identified 11 (11.8%) PML-IRIS cases among 93 patients with definite PML. Eight (73%) cases were men and had a median (IQR) age of 41 (27–50) years. Seven (63.6%) patients developed unmasking PML-IRIS and 4 (36.4%) had paradoxical PML-IRIS. The median (IQR) time from initiation of combined antiretroviral therapy (cART) to IRIS diagnosis was 49 (30–70) days. Ten (90.9%) patients received corticosteroids. There were 4 (36%) in-hospital deaths and 3 were associated with hospital-acquired pneumonia. Among the 7 (64%) patients who survived, 5 (71.5%) had sequelae at discharge. One year after the PML-IRIS diagnosis, 6 (54.5%) patients were alive. Conclusion The prevalence of PML-IRIS was 11.8%. Most patients had unmasking PML-IRIS. In-hospital mortality and morbidity were high. One-year survival was similar to that described in some high-income countries.