High Rates of Recurrence in HIV-Infected and HIV-Uninfected Patients with Tuberculosis

Background. The rate of recurrent tuberculosis disease due to reinfection, compared with the incidence of new tuberculosis, in those with and without HIV infection is not known. Methods. In a retrospective cohort study of South African gold miners, men with known dates of seroconversion to HIV (from 1991 to 1997) and HIV-negative men were followed up to 2004. Rates of tuberculosis recurrence >2 years after the first episode were used as a proxy for reinfection disease rates. Results. Among 342 HIV-positive and 321 HIV-negative men who had had 1 previous episode of tuberculosis, rates of recurrence were 19.7 cases per 100 person-years at risk (PYAR; 95% confidence interval [CI], 16.4-23.7) and 7.7 cases per 100 PYAR (95% CI, 6.1-9.8), respectively. The recurrence rate did not vary by duration of HIV infection. Recurrent pulmonary tuberculosis rates >2 years after the first episode were 24.4 cases per 100 PYAR (95% CI, 17.2-34.8) in HIV-positive men and 4.3 cases per 100 PYAR (95% CI, 2.2-8.3) in HIV-negative men, compared with incidence rates of new pulmonary tuberculosis of 3.7 cases per 100 PYAR (95% CI, 3.3-4.1) in HIV-positive men and 0.75 cases per 100 PYAR (95% CI, 0.67-0.84) in HIV-negative men in the same cohort. Conclusions. Tuberculosis recurrence rates, likely due to reinfection, were much higher than incidence rates. The findings suggest heterogeneity in susceptibility, implying that a vaccine could still provide useful protection in the population and strengthening the case for secondary preventive therapy.