Tuberculosis associated with HIV infection

Tuberculosis (TB) and HIV infection continue to be major global health threats. While deaths related to HIV infection have decreased markedly over recent years, reductions in TB-related mortality has not kept pace, and in 2014, for the first time, TB surpassed HIV as the number 1 cause of infectious disease-related death. In the 1990s, HIV fueled the reemergence of the TB epidemic (¹), and even today, TB continues to disproportionately affect persons living with HIV. Among 9.6 million people with incident TB in 2014 (²), 1.2 million (12%) were HIV positive, and of the 1.5 million people who died from TB that same year, 400,000 (33%) were coinfected with HIV (³). TB remains the leading cause of death among HIV-infected persons. HIV substantially increases the risk of progression from latent TB infection (LTBI) to active disease. The World Health Organization (WHO) estimates that among individuals with LTBI, people living with HIV have a 26-fold-higher risk of progression to TB disease than those without HIV (³). HIV and TB thus display lethal synergy, with HIV-associated immunosuppression triggering markedly increased susceptibility to TB and TB accelerating HIV-associated morbidity and mortality. Here, we review the pathogenesis, epidemiology, and clinical aspects of HIV-related TB.