Brief Report: The Effect of Antiretroviral Therapy and CD4 Count on Markers of Infectiousness in HIV-Associated Tuberculosis.

Clinical features of tuberculosis influence infectiousness. This cross-sectional study examined the effect of combination antiretroviral therapy (cART) and CD4 on sputum smear-positivity (SS+) and pulmonary cavitation among 1589 (1185/1589 HIV-positive) miners in South Africa. Proportions SS+ varied nonlinearly by CD4 with greatest proportions SS+ (55.3%) in the lowest stratum (<100 cells/μL). Adjusted prevalence ratio for SS+; on vs. off cART was 0.90 (95% confidence interval: 0.73 to 1.11). Proportions with cavitation varied linearly with CD4, with no independent cART effect (adjusted prevalence ratio 1.17; 95% confidence interval: 0.80 to 1.71). cART did not independently affect SS+ or cavitation but may increase infectiousness through CD4 recovery.