Prevalence and Mortality due to Mycobacterium tuberculosis Bloodstream Infection in Adults With HIV: A Multicountry Prospective Cohort Study.

BACKGROUND

HIV-associated tuberculosis is a leading cause of mortality. Mycobacterium tuberculosis bloodstream infection (MTB-BSI) is complicated by diagnostic difficulty and severe illness. We assessed whether MTB-BSI continues to be common in the era of widespread antiretroviral therapy and whether it continues to result in increased risk of early mortality.

METHODS

We enrolled inpatients from medical wards irrespective of tuberculosis symptoms and outpatients with tuberculosis symptoms. All participants had HIV and were ≥18 years old, and all were recruited from 7 countries: Malawi, South Africa, Tanzania, Thailand, Uganda, Vietnam, and Zambia. Participants also had <3 doses of antituberculosis treatment in the past 60 days and no isoniazid preventive therapy in the past 6 months. We estimated the prevalence of MTB-BSI. In Bayesian survival models, we estimated the hazards of mortality for inpatients with MTB-BSI vs those without.

RESULTS

Between 2019 and 2021, 1703 participants were included: 44% were hospitalized, the median CD4 count was 361 cells/μL, and 77% reported using antiretroviral therapy. Crude prevalence of MTB-BSI varied by country but was 4.4% (32/723) among all inpatients, 22.5% (32/142) among inpatients with microbiologically confirmed TB, and 0.2% (2/913) among all outpatients. Among all inpatients, those with MTB-BSI had 2.65-times (95% credible interval, 1.06-5.01) increased hazard of death by 30 days and 1.79-times (95% credible interval, .81-3.11) increased hazard by 70 days. Lower CD4 and older age were strongly associated with mortality.

CONCLUSIONS

MTB-BSI is far more common for inpatients than outpatients with HIV. Across multiple settings with high tuberculosis prevalence, MTB-BSI was strongly associated with heightened risk of early mortality in PWH. Novel optimized diagnostic and treatment strategies are still needed for HIV-associated MTB-BSI.