Genetic mutations are responsible for the high rate of resistance observed in the treatment of tuberculosis. This study aimed at determining the occurrence of mutations associated with rifampicin (RIF) and isoniazid (INH) resistance of Mycobacterium tuberculosis complex (MTBC) isolates. MTBC strains isolated by culture from 110 TB patients diagnosed with resistant to rifampicin (RR-TB) by Xpert MTB/RIF were studied. The isolates were obtained from the National Tuberculosis Reference Laboratory in Ouagadougou. They were identified culturally using Antigenic method (SD Bioline TB Ag MPT64). Polymerase Chain Reaction, PCR (DRplus) was used to detect the occurrence of mutations in the genes associated with resistance katG and inhA promoter for INH, and rpoB for RIF. Out of 103 isolates with RIF resistant, mutations were detected in 87(84.5%) of gene rpoB while no mutation was found in 16(15.5%) of the gene of the isolates even though the wild probes had disappeared. Single mutations were found in the codons D516V (41.7%) and H526Y (17.5%) while combined mutations (single and double) were mostly detected in the codons D516 (51.5%), H526Y (20.4%), S531L (11.7%) and H526D (10.7%) respectively. Single mutations responsible for high-level isoniazid resistance, katG were observed in the codon S315T1 while the combined inhA and katG were detected in the codon C8T and S315T, 16 (14.5%) respectively. The highest mutation occurrence was observed with rpoB516, rpoB526 for RIF and katG315 for INH associated with resistance of MTBC isolates. There is a need to improve molecular assay kit diagnosis to curb the geographic specificity of the target genes needed to detect more possible mutations.

Abstracts: Contaminated milk and milk-products are regarded as vehicles for the transmission of Campylobacteriosis, infectious diarrhoea caused by Campylobacter but the prevalence of this bacterium in nunu had not been established. This study aimed at determining the prevalence of Campylobacter species in locally pasteurized milk product (nunu) sold in Zaria metropolis and establish the antibiotic resistance pattern of the isolates. A total of 180 nunu samples were collected and cultured for Campylobacter species using membrane filtration method, characterized using biochemical testing and API campy kits. Susceptibility of the isolates was carried out using the conventional agar diffusion method and the MAR indexing was calculated respectively. Out of the 180 nunu samples, 29 samples were positive for Campylobacter species giving a prevalence of 16.1%. Campylobacter coli were mostly isolated with isolation rate of 10.5% while C. jejuni were 5.6%. Imipenem were found to have 100% efficacy against all the Campylobacter species followed by Gentamicin (95%) while the isolates were resistant to Erythromycin (100%). Altogether, 39% of the Campylobacter species were resistant to three and more class of antibiotics and this is mostly implicated among strains of Campylobacter coli (47%) compared to C. jejuni (31%). The highest MAR index of 0.63 observed in this study is of public health importance. In this study, all the isolates had a MAR index greater than 0.2. Thus, Campylobacter contamination of the milk product is likely to be from a high risk source. With the increasing trend in Campylobacter resistance, it is therefore recommended that the use of antibiotic in animal food production and human therapy had to be controlled.