Identifying Mycobacterium Tuberculosis Resistance to Rifampin by Multiplex Specific PCR Method

Abstract

Background and Objectives: Mycobacterium tuberculosis is still considered the most common cause of death cases related to pathogenic infectious factors in the world. Rifampin is among the most important first-line drugs to treat tuberculosis. The most common mutations in resistance to Rifampin occur due to the displacements in Codons 531, 526, and 516 in rpoB gene. This study was carried out with the aim of introducing the method (Multiplex Allele Specific) PCR in order to identify tuberculosis patients resistant to rifampin through detecting mutations in the rpoB gene.Methods: In this study, three cases of mutation were evaluated in three Codons of rpoB gene in 90 samples of the positive cases of culture from pulmonary TB patients who had referred to Research Center of Mycobacteriology located in Masih-Daneshvari Hospital of Tehran from 1385 to 1387 after the drug sensitivity test. To examine three codons 531, 526 and 516, MAS PCR method was used. Results: The results of the culture showed that 33.3% of the samples were sensitive and 66.6% were resistant to drugs of which 44.4% were resistant to Rifampin. By using MAS PCR method, 32.2% of these cases of resistance were identified. Among these cases, 43.4% had mutation in codon rpoB 531, 34.5% in rpoB 526 codon and 31% in rpoB 516 codon. Conclusion: Based on the results of this study, MAS PCR method used in this research is an accurate and appropriate method to rapidly diagnose resistance to Rifampin in the clinical samples of Mycobacterium tuberculosis.

Keywords

• Tuberculosis
• Drug Resistance
• Rifampin
• Polymerase Chain Reaction