High prevalence of childhood multi-drug resistant tuberculosis in Johannesburg, South Africa: a cross sectional study

Background: There are limited data on the prevalence of multi-drug resistant tuberculosis (MDR-TB), estimated at 0.6-6.7%, in African children with tuberculosis. We undertook a retrospective analysis of the prevalence of MDR-TB in children with Mycobacterium tuberculosis (MTB) at two hospitals in Johannesburg, South Africa. Methods: Culture-confirmed cases of MTB in children under 14 years, attending two academic hospitals in Johannesburg, South Africa during 2008 were identified and hospital records of children diagnosed with drug-resistant TB were reviewed, including clinical and radiological outcomes at 6 and 12 months post-diagnosis. Culture of Mycobacterium tuberculosis complex (MTB) was performed using the automated liquid broth MGIT (TM) 960 method. Drug susceptibility testing (DST) was performed using the MGIT (TM) 960 method for both first and second-line anti-TB drugs. Results: 1317 children were treated for tuberculosis in 2008 between the two hospitals where the study was conducted. Drug susceptibility testing was undertaken in 148 (72.5%) of the 204 children who had culture-confirmed tuberculosis. The prevalence of isoniazid-resistance was 14.2% (n = 21) (95% CI, 9.0-20.9%) and the prevalence of MDR-TB 8.8% (n = 13) (95% CI, 4.8-14.6%). The prevalence of HIV co-infection was 52.1% in children with drug susceptible-TB and 53.9% in children with MDR-TB. Ten (76.9%) of the 13 children with MDR-TB received appropriate treatment and four (30.8%) died at a median of 2.8 months (range 0.1-4.0 months) after the date of tuberculosis investigation. Conclusions: There is a high prevalence of drug-resistant tuberculosis in children in Johannesburg in a setting with a high prevalence of HIV co-infection, although no association between HIV infection and MDR-TB was found in this study. Routine HIV and drug-susceptibility testing is warranted to optimize the management of childhood tuberculosis in settings such as ours.