HAART and risk of tuberculosis in HIV-infected South African children: a multi-site retrospective cohort

Abstract

Setting: Four human immunodeficiency virus (HIV) clinics located at South African tertiary hospitals.

Objective: To assess the effectiveness of highly active antiretroviral therapy (HAART) in reducing incident tuberculosis (TB) in HIV-infected children.

Design: Retrospective cohort.

Results: A total of 1132 children's records were included in the study. At entry to the cohort, the median (interquartile range [IQR]) age, CD4%, CD4 count and viral load of all children was respectively 6.3 years (4.1-8.8), 15% (9.0-22.2), 576 cells/mm(3) (287-960) and 160 000 copies/ml (54 941.5-449 683); 75.9% were started on HAART. The male:female ratio was 1:1, and median follow-up time was 1.7 years. In children whose follow-up included both pre-HAART and on-HAART periods, the incidence of clinically diagnosed TB was respectively 21.1 per 100 person-years (py; 95%CI 18.2-24.4) and 6.4/100 py (95%CI 4.8-8.1), and when restricted to confirmed cases, respectively 3.1/100 py (95%CI 2.2-4.2) and 0.8/100 py (95%CI 0.5-1.4). Only 23% of all cases of TB were microbiologically confirmed. Multivariate analyses showed that HAART reduced incident TB by approximately 70%, both for confirmed and all TB cases.

Conclusions: In this high TB burden country, the incidence of diagnosis of TB in HIV-infected children is at least as high as that of adults. HAART reduces incident TB, but further prospective TB preventive and diagnostic studies are urgently needed in children.

Figure

Incidence of TB (per 100 person-years) stratified by period before or during HAART. Re- stricted to children who had follow-up time before and during HAART (‘dual’ children). HAART = highly active antiretroviral therapy; TB = tuberculosis.