RESEARCH ON rpoB GENE MUTATIONS OF Mycobacterium tuberculosis RESISTANT TO RIFAMPICIN IN VINH LONG LUNG HOSPITAL

Introduction: Rifampicin resistance due to infection with Mycobacterium tuberculosis can be mutated on many typical genes and some related genes, especially rpoB gene of tuberculosis patients treated at Vinh Long lung hospital with molecular biotechnological techniques with high-precision to identify mutations in resistance genes to helps doctors treat patients effectively. Research objectives: (1) Determine the rate of rifampicin resistance by rpoB gene sequencing on Mycobacterium tuberculosis from patients treated in the hospital and some related factors in tuberculosis patients at Vinh Long Lung Hospital. (2) Determine the rate and type of mutations in rpoB gene in tuberculosis patients resistant to rifampicin. Subjects and research methods: A cross-sectional descriptive study on 412 patients with GeneXpert test results with TB bacteria at Vinh Long Lung Hospital. Results: Rifampicin resistance rate by Gene Xpert technique in patients with tuberculosis is 4.6%. The relapsed TB group has a higher rate of rifampicin resistance compared with the new TB group (p<0.001). The group of civil servants has a rate of rifampicin resistance 31 times higher than that of the farmer group with p=0.019. Gene sequence analysis of 14 cases of rifampicin resistance shows that there are 2 mutated codon positions, 531 and 526, in which codon position 531 is mutated at the S531L position of Ser → Leu with 08 samples accounting for 57.1% of mutations, at the H526N position, His → Asn has 02 samples, accounting for 14.3%, the H526L position changes from His → Leu has 02 samples, accounting for 14.3%, the H526D position changes from His → Asp has 01 sample accounting for. 7.1% and the position of H526Y changes from His → Tyr has 01 sample, accounting for 7.1%. Mutation sites on the rpoB gene are found in codon 526 and codon 531. Conclusion: The rate of Rifampicin resistance at Vinh Long Lung Hospital is quite high. There is a relation between Rifaminicin resistance with prehistory of tuberculosis treatment (p<0.001) and occupation (p<0.019). Mutation sites of the rpoB gene are found at codons 526 and 531, respectively.