MOLECULAR TYPING AND DRUG RESISTANCE IN <i>MYCOBACTERIUM TUBERCULOSIS</i> COMPLEX ISOLATES FROM JAMOT AND MBALMAYO DISTRICT HOSPITALS, CAMEROON

Background Cameroon is a country where tuberculosis still remains a major public health problem. The aim of the present research was to evaluate the potential of molecular markers in predicting first-line drug resistance and to investigate the predominant genotypes representative of Mycobacterium tuberculosis strains in the Centre region of Cameroon. Methods A total of 169 strains of M. tuberculosis isolate from the Centre Region of Cameroon were screened for mutations associated with first-line drug resistance by DNA sequence analysis. Spoligotyping and MIRU-VNTR (24 loci; mycobacterial interspersed repetitive units typing – variable number tandem repeat) were combined to identify clustered isolates. Results Rifampicin-resistant strains had the rpoB mutations D516V, H526D or S531L; isoniazid-resistant strains had the mutations katG S315T or inhA promoter C15T; streptomycin-resistant strains had the mutations rpsL K43R, gidB V36G, H48N, P75S, L79W, or A138P; ethambutol-resistant strains had the mutation embB M306V. Among those M. tuberculosis isolates, 52.5% isolates were Cameroon genotypes followed by Haarlem genotype (22.1%). The frequencies of isoniazid, rifampin, streptomycin and multidrug-resistant isolates were equally distributed in Cameroon genotype strains and non-Cameroon strains. Furthermore, the analysis also shows the very low frequency of M. africanum since only 2.6% of isolates belong to this species. Conclusions Mutations of common genes known to be involved in resistance had high specificities in detecting resistance. This study reveals the highly diverse M . tuberculosis population structure, It confirms a predominance of the Cameroon lineage in the Centre Region of Cameroon and the disappearance of M. africanum in Cameroon.