Extensively drug resistant tuberculosis in Mali: a case report

Abstract Background Drug resistant tuberculosis presents a major public health challenge. Case presentation We present here the first two patients diagnosed with extensively drug resistant tuberculosis in Bamako, Mali. Genotypic findings suggest possible nosocomial transmission from the first patient to the second one, resulting in superinfection of the second patient. After being diagnosed with extensively drug resistant tuberculosis in August 2016, the patients only started receiving appropriate treatment 10 months later. Conclusion The identification of these patients highlights the need for improved diagnostic and treatment algorithms for better surveillance and management of drug resistance in Mali. In the interest of these as well as future patients suffering from resistant tuberculosis, all steps recommended for programmatic management of drug resistant tuberculosis must be urgently prioritized in order to strengthen the multidrug resistant tuberculosis program

The most frequent Mycobacterium tuberculosis complex families in mali (2006–2016) based on spoligotyping

Background: To identify strains of Mycobacterium tuberculosis complex (MTBc) circulating in Bamako region during the past 10 years. Methods: From 2006 to 2016, we conducted a cross-sectional study to identify with spoligotyping, clinical isolates from tuberculosis (TB)-infected patients at different stages of their treatments in Bamako, Mali. Results: Among the 904 suspected TB patients included in the study and thereafter tested in our BSL-3 laboratory, 492 (54.4%) had MTBc and therefore underwent spoligotyping. Overall, three subspecies, i.e., MTB T1 (31.9%) and MTB LAM10 (15.3%) from lineage 4 and M. africanum 2 (16.8%) from lineage 6 were the leading causes of TB in Bamako region during the past 10 years. Other spoligotypes such as MTB T3, MTB Haarlem 2, MTB EAI3, and MTB family 33 were also commonly seen from 2010 to 2016. Conclusion: This study showed a high genetic diversity of strains isolated in Bamako region and highlights that M. tuberculosis T1 strain was the most prevalent. Furthermore, the data indicate an increasing proportion of primary drug resistance overtime in Bamako

Mycobacterium africanum (Lineage 6) shows slower sputum smear conversion on tuberculosis treatment than Mycobacterium tuberculosis (Lineage 4) in Bamako, Mali.

ObjectiveAncestral M. tuberculosis complex lineages such as M. africanum are underrepresented among retreatment patients and those with drug resistance. To test the hypothesis that they respond faster to TB treatment, we determined the rate of smear conversion of new pulmonary tuberculosis patients in Bamako, Mali by the main MTBc lineages.MethodsBetween 2015 and 2017, we conducted a prospective cohort study of new smear positive pulmonary tuberculosis patients in Bamako. Confirmed MTBc isolates underwent genotyping by spoligotyping for lineage classification. Patients were followed at 1 month (M), 2M and 5M to measure smear conversion in auramine (AR) and Fluorescein DiAcetate (FDA) vital stain microscopy.ResultAll the first six human MTBc lineages were represented in the population, plus M. bovis in 0.8% of the patients. The most widely represented lineage was the modern Euro-American lineage (L) 4, 57%, predominantly the T family, followed by L6 (M. africanum type 2) in 22.9%. Ancestral lineages 1, 5, 6 and M. bovis combined amounted to 28.8%. Excluding 25 patients with rifampicin resistance, smear conversion, both by AR and FDA, occurred later in L6 compared to L4 (HR 0.80 (95% CI 0.66-0.97) for AR, and HR 0.81 (95%CI 0.68-0.97) for FDA). In addition we found that HIV negative status, higher BMI at day 0, and patients with smear grade at baseline ≤ 1+ were associated with earlier smear conversion.ConclusionThe six major human lineages of the MTBc all circulate in Bamako. Counter to our hypothesis, we found that patients diseased with modern M. tuberculosis complex L4 respond faster to TB treatment than those with M. africanum L6