Drug-susceptibility Patterns of Mycobacterium tuberculosis in Mpumalanga Province, South Africa: Possible Guiding Design of Retreatment Regimen

AIDS Virus Research Laboratory, Department of Microbiology, University of Venda, South Africa.
Journal of Health Population and Nutrition (Impact Factor: 1.04). 02/2010; 28(1):7-13. DOI: 10.3329/jhpn.v28i1.4518
Source: PubMed


Multidrug-resistant tuberculosis (MDR-TB) has been a cause of concern in both developed and developing countries. The prevalence of drug resistance in Mycobacterium tuberculosis (MTB) isolates (n=692) from Mpumalanga province was assessed. In total, 692 (64%) MTB strains from cases with pulmonary TB were tested for susceptibility against rifampicin, isoniazid, ethambutol, and streptomycin using the MGIT 960 instrument. Two hundred and nine (30.2%) strains were resistant to one or more drugs. Resistance to one drug ranged from 1.4% for ethambutol to 17.7% for rifampicin. The prevalence of MDR-TB ranged from 6.7% for three drugs to 34% for four drugs, with significant predictors being patients' age-groups of 25-54 years (p=0.0012) and >55 years (p=0.007). The result showed a high level (58.4%) of MDR-TB from cases in Mpumalanga province. To achieve a higher cure rate in this province, drug-susceptibility tests must be done for every case.

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    • "Two recent follow-up studies evaluating this regimen observed, even after cure, very high rates of recurrence in TB patients with MDR-TB at base-line [21,22]. Notwithstanding, most TB programmes in low-income countries in sub-Saharan Africa treat, empirically, every year 10-20% of their TB patients using this regimen [2,15,19]. The design of NTP retreatment regimens depends on the epidemiological context, the program's performance, and the means available. "
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