Prevalence and Molecular Mapping of Multidrug-resistant Mycobacterium tuberculosis in Sokoto, North-Western Nigeria

Abstract

Background: The emergence of multidrug-resistant tuberculosis tuberculosis (MDR-TB) poses a significant danger to Nigeria’s TB control efforts. Nigeria records 570 000 new TB cases each year, and it is one of the world’s greatest TB-burden countries as well as one of the top ten countries with MDR-TB. This study aimed to determine the MDR prevalence, phylogenetic analysis, and molecular mapping as well as the link between MDR prevalence and demographic data. Methods: The study comprised 100 TB patients recruited consecutively. The proportion method on Lowenstein-Jensen (LJ) medium was used for drug susceptibility testing. Conventional polymerase chain reaction (PCR) was used, and the rrs genes were amplified and sequenced. Multiple sequence alignment techniques were used to compare the PCR product sequences to reference sequences retrieved from GenBank. Results: Rifampicin (RIF) resistance was found in 29% (22.75), ethambutol resistance was found in 20% (15.75), and isoniazid (INH) resistance was found in 28% (21.75). Further, RIF and INH resistance were found in 20% (15.75) of the samples. At nucleotide position 892, four isolates (31%) contained a G-A transition, and the most prevalent mutation found in the rrs gene was S531L (80%, 12.15). The phylogenetic analysis indicated that three of the Sokoto isolates are closely linked to reference isolates from Iran, Germany, China, and Sudan in terms of geographical relatedness. Conclusions: The obtained data revealed that acquired resistance is a major factor in the establishment of MDR-TB in Sokoto, which could be owing to poor adherence to medication or poor treatment of TB patients.