Mpox severity and associated hospitalizations among people with HIV and related immunosuppression in Brazil.

Objectives: This study aimed to analyze characteristics of mpox hospitalization in a Brazilian cohort, further exploring the impact of HIV on mpox-related outcomes and hospitalization.

Design: We conducted a descriptive analysis, comparing characteristics of individuals diagnosed with mpox according to hospitalization and HIV status, and described the mpox cases among those living with HIV.

Methods: This was a single-center, prospective cohort study conducted at a major infectious diseases referral center in Rio de Janeiro, Brazil, that enrolled participants older than 18 years of age diagnosed with mpox. Information was collected on standardized forms, including data on sociodemographic, behavioral, clinical and laboratory characteristics. For comparisons, we used chi-squared, Fisher's exact and the Moods median tests whenever appropriate.

Results: From June to December, 2022, we enrolled 418 individuals diagnosed with mpox, of whom 52% were people with HIV (PWH). PWH presented more frequently with fever, anogenital lesions and proctitis. The overall hospitalization rate was 10.5% ( n  = 43), especially for pain control. Among hospitalized participants, PWH had more proctitis and required invasive support. Mpox severity was related to poor HIV continuum of care outcomes and low CD4 + cell counts. All deaths ( n  = 2) occurred in PWH with CD4 + less than 50 cells/μl.

Conclusion: HIV-related immunosuppression likely impacts mpox clinical outcomes. This is of special concern in settings of poor adherence and late presentation to care related to socioeconomic inequalities, such as Brazil. The HIV continuum of care must be taken into account when responding to the mpox outbreak.