Ismail NA, et al. - The prevalence of resistance to tuberculosis drugs in newly diagnosed and retreated patients with tuberculosis was estimated provincially and nationally. Further, the estimate was compared with the 2001–02 estimates. In 2012–14, data from South Africa showed an overall prevalence of multidrug-resistant (MDR) tuberculosis similar to that observed in 2001–02. However, new cases displayed almost double prevalence of rifampicin-resistant tuberculosis. Furthermore, empirical management is suggested in view of the high prevalence of isoniazid mono-resistant tuberculosis, not routinely screened for, and resistance to second-line drugs.

Methods

• From June 15, 2012 to June 14, 2014, a cross-sectional survey using population proportionate randomised cluster sampling in the nine provinces in South Africa was performed.
• Researchers included 343 clusters, ranging between 31 and 48 per province.
• Inclusion criteria included presenting as a presumptive case during the intake period at a drug resistance survey enrolling facility.
• A questionnaire was administered to consenting participants (≥18 years old) and their sputum sample were tested for resistance to first-line and second-line drugs.
• For this study, analysis was by logistic regression with robust SEs, inverse probability weighted against routine data, and estimates were derived using a random effects model.

Results

• In 2012–14, researchers identified 101,422 participants who were tested.
• Among new tuberculosis cases, the MDR tuberculosis prevalence of 2·1% (95% CI 1·5–2·7) and among retreatment cases, of 4·6% (3·2–6·0) was noted nationally.
• Observations revealed that MDR tuberculosis provincial point prevalence ranged between 1·6% (95% CI 0·9–2·9) and 5·1% (3·7–7·0).
• Overall, higher prevalence of rifampicin-resistant tuberculosis (4·6%, 95% CI 3·5–5·7) was noted in comparison to the prevalence of MDR tuberculosis (2·8%, 2·0–3·6; p=0·01).
• The current survey and previous (2001–02) survey displayed the overall MDR tuberculosis prevalence of 2·8% vs 2·9% and rifampicin-resistant tuberculosis prevalance of 3·4% vs 1·8%, respectively.
• All provinces showed isoniazid mono-resistant tuberculosis prevalence of above 5%.
• Among MDR tuberculosis cases, the prevalence of ethionamide and pyrazinamide resistance was 44·7% (95% CI 25·9–63·6) and 59·1% (49·0–69·1), respectively.
• Findings showed the prevalence of XDR tuberculosis of 4·9% (95% CI 1·0–8·8).
• For 2014, the estimated numbers of cases of rifampicin-resistant tuberculosis, MDR tuberculosis, and isoniazid mono-resistant tuberculosis nationally were 13,551, 8249, and 17,970, respectively.