Multidrug-Resistant Tuberculosis in the Democratic Republic of Congo: Analysis of Continuous Surveillance Data from 2007 to 2016

Abstract

Background: For countries with limited resources such as the Democratic Republic of the Congo (DRC), the diagnosis of Multidrug-resistant tuberculosis (MDR-TB) is still insufficient. The MDR-TB identification is done primarily among at-risk groups. The knowledge of the true extent of the MDR-TB remains a major challenge. This study tries to determine the proportion of MDR-TB in each group of presumptive MDR-TB patients and to identify some associated factors. Methods: This is an analysis of the DRC surveillance between 2007 and 2016. The proportions were expressed in Percentage. The logistic regression permits to identify the associated factors with the RR-/MDR-TB with adjusted Odds-ratio and 95% CI. Significance defined as p ≤ 0.05. Results: Overall, 83% (5407/6512) of the MDR-TB presumptive cases had each a TB test. 86.5% (4676/5407) had each a culture and drug sensitive testing (DST) on solid medium, and 24.3% (1312/5407) had performed an Xpert MTB/RIF test. The proportion of those with at least one first-line drug resistance was 59.3% [95% CI 57.2 - 61.4] among which 50.1%, [95% CI 47.9 - 52.3] for the isoniazid, 45.6% [95% CI 43.4 - 47.8] for the rifampicin, 49.9% [95% CI 47.8 - 52.1] for ethambutol and 35.8% [95% CI 33.7 - 37.9] for streptomycin. The confirmation of MDR-TB was 42.8% [95% CI 38.4 - 47.8]. Combining both tests, the proportion of RR-/MDR-TB was 49.6% [95% CI 47.9 - 51.4] for all presumptives. This proportion was 60.0% for failures, 40.7% for relapses and 34.7% for defaulters. Associated factors with the diagnosis of MDR-TB were: aged less than 35 years; prior treatment failure; defaulters; the delay between the collection of sputum and the test completion. Conclusion: The proportion of RR-/MDR-TB among the presumptives has been higher than those estimated generally. The National tuberculosis programme (NTP) should improve patient follow-up to reduce TB treatment failures and defaulting. Moreover, while increasing the use of molecular tests, they should reduce sample delivery times when they use culture and DST concomitantly.