Epidemic Levels of Drug Resistant Tuberculosis (MDR and XDR-TB) in a High HIV Prevalence Setting in Khayelitsha, South Africa

Helen S Cox,Virginia Azevedo,Odelia Muller,Eric Goemaere,Gilles Van Cutsem,Gerrit Coetzee,Marinus Barnard,Cheryl Mcdermid,David Coetzee,John Simpson,Ben Marais

doi:10.1371/journal.pone.0013901

Helen S Cox, Virginia Azevedo + Show 9 more

Open Access

https://doi.org/10.1371/journal.pone.0013901

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Abstract

BackgroundAlthough multidrug-resistant tuberculosis (MDR-TB) is emerging as a significant threat to tuberculosis control in high HIV prevalence countries such as South Africa, limited data is available on the burden of drug resistant tuberculosis and any association with HIV in such settings. We conducted a community-based representative survey to assess the MDR-TB burden in Khayelitsha, an urban township in South Africa with high HIV and TB prevalence.Methodology/Principal FindingsA cross-sectional survey was conducted among adult clinic attendees suspected for pulmonary tuberculosis in two large primary care clinics, together constituting 50% of the tuberculosis burden in Khayelitsha. Drug susceptibility testing (DST) for isoniazid and rifampicin was conducted using a line probe assay on positive sputum cultures, and with culture-based DST for first and second-line drugs. Between May and November 2008, culture positive pulmonary tuberculosis was diagnosed in 271 new and 264 previously treated tuberculosis suspects (sample enriched with previously treated cases). Among those with known HIV status, 55% and 71% were HIV infected respectively. MDR-TB was diagnosed in 3.3% and 7.7% of new and previously treated cases. These figures equate to an estimated case notification rate for MDR-TB of 51/100,000/year, with new cases constituting 55% of the estimated MDR-TB burden. HIV infection was not significantly associated with rifampicin resistance in multivariate analyses.Conclusions/SignificanceThere is an extremely high burden of MDR-TB in this setting, most likely representing ongoing transmission. These data highlight the need to diagnose drug resistance among all TB cases, and for innovative models of case detection and treatment for MDR-TB, in order to interrupt transmission and control this emerging epidemic.

Highlights

There are an estimated 13,000 cases of multidrug-resistant tuberculosis (MDR-TB) emerging in South Africa each year [1]
While expanding access to antiretroviral treatment (ART) is expected to reduce tuberculosis case notifications, it may contribute to the large pool of individuals with increased vulnerability to TB created by the HIV epidemic [4]
Eastern Europe and the former Soviet Union have been described as global ‘‘hot spots’’ for tuberculosis drug resistance [14]. This has primarily been based on assessments of the proportion of all TB cases suffering from drug resistant disease

Summary

Introduction

There are an estimated 13,000 cases of multidrug-resistant tuberculosis (MDR-TB) emerging in South Africa each year [1]. While expanding access to ART is expected to reduce tuberculosis case notifications, it may contribute to the large pool of individuals with increased vulnerability to TB created by the HIV epidemic [4]. The convergence of these conditions: the high rate of tuberculosis prevalence, a vulnerable population and the existence of undiagnosed and untreated drug resistant tuberculosis create the potential for dramatically increasing epidemics. Multidrug-resistant tuberculosis (MDR-TB) is emerging as a significant threat to tuberculosis control in high HIV prevalence countries such as South Africa, limited data is available on the burden of drug resistant tuberculosis and any association with HIV in such settings. We conducted a community-based representative survey to assess the MDRTB burden in Khayelitsha, an urban township in South Africa with high HIV and TB prevalence

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