Molecular Diagnosis of Resistant Tuberculosis Against Rifampicin to the Patients of the Centre Hospitalier Universitaire de Référence Nationale (CHU-RN): Preliminary Study During the COVID-19 Pandemic Period in N'Djamena, Chad

Background: The fight against Tuberculosis (TB) remains a challenging public health problem worldwide. Nowadays, resistance forms increase sharply in developed countries. With a rifampicin resistance rate of 7.2% higher than the World Health Organization (WHO) level, the Tuberculosis Control Program in Chad has many challenges to overcome in the fight against resistant and multiresistant forms of TB. This present study aims to evaluate the proportion of resistant tuberculosis against rifampicin at the Centre Hospitalier Universitaire de Référence Nationale (CHU-RN) of N’Djamena in Chad. Material and Methods: From August 1st to December 31st, 2020, sputum samples collected in the laboratory of CHU-RN were automatically included in our study. We directly analyzed sputum samples using the GeneXpert MTB/RIF, which is a molecular diagnosis method, to identify the sensitivity of the Mycobacterium tuberculosis complex to rifampicin. Results: The study population consisted of 680 sputum samples collected. It was mainly represented by men (66.62%), with a ratio sex of about 1.99. The age range varies from 2 to 85 years old. Most of the patients in the study lived in N’Djamena (95.68%), and 4.32% were from other localities. Mycobacterium tuberculosis Complex (MTBC) was detected in 51.63% (N = 696), including 244 men and 104 women (a sex ratio of 2.35). Many tuberculosis patients are young people aged 15–34 (49.14%). Children whose samples tested positive for TB accounted for 2% of the 348 MTBC-positive samples, 7.18% (20 males and 5 females) were resistant to rifampicin, confirming a rifampicin sensitivity of 92.53%. Among these 25 cases of rifampicin resistance, 15 patients (4.31%) were already treated, and the other 10 patients represented new cases of TB (2.87%). Conclusion: This study showed 7.18% resistance to rifampicin. These results highlighted the question linked to the post-COVID-19 period. The DOTS strategy should include the use of Xpert MTB/RIF® technology in all provinces of Chad. This will lead to the early detection of new cases of TB and MDR-TB. Overall, it will provide rapid treatment, as recommended by the WHO for developing countries like Chad.