Objective: To assess the impact of HIV infection upon the development, clinical presentation, and outcome of tuberculosis (TB) among children.
Design: Case-control study and prospective cohort study.
Methods: From March 1994 to November 1995, children aged 0-9 years with newly diagnosed TB were enrolled at the two outpatient TB centers and the two principal university hospitals in Abidjan, Côte d'Ivoire. Children were examined, blood samples were collected for HIV serology and lymphocyte phenotyping, chest radiography was performed, and gastric aspirates and sputum samples were collected for acid-fast bacilli smear and culture. Children were then followed every 2 months during a standard 6-month course of anti-TB therapy. To examine risk factors for TB, age- and sex-matched healthy control children were enrolled from among the siblings of children referred for TB skin testing.
Results: Overall, 161 children with TB were enrolled, including 39 (24%) with culture-confirmed pulmonary TB, 80 (50%) with clinically diagnosed pulmonary TB, and 42 (26%) with extrapulmonary TB. Children with TB were significantly more likely than 161 control children to be HIV-seropositive (19 versus 0%), to have a past TB contact (55 versus 16%) and to live in very low socioeconomic status housing (24 versus 6%). No significant differences between HIV-seropositive and seronegative children were found in the distribution of radiologic abnormalities for pulmonary TB or in the site of extrapulmonary TB. The mortality rate in HIV-seropositive children was significantly higher than in seronegative children (23 versus 4%; relative risk, 3.6; 95% confidence interval, 2.0-6.6), and all deaths in HIV-seropositive children with available lymphocyte subtyping results occurred in those with a CD4 percentage of < 10%.
Conclusions: This study documents the importance of HIV infection as an independent risk factor for the development of TB in children, and demonstrates that HIV-related immunosuppression is a critical risk factor for mortality in this population.