Microbiologia Médica e Diagnóstico

Tuberculosis pathogenicity, drug resistance and molecular diagnostic methods

Abstract

Zoha Tavakkoli

Aim and objective: Tuberculosis associated whit drug resistances is one of the most important infectious diseases in the world today. A High Resolution Melting Analysis (HRM) was expanded to detect Isoniazid (INH) and Rifampin (RMP) in Mycobacterium tuberculosis by targeting resistance related mutations in the katG, rpoB, inhA genes in this study we aimed nature and frequency of this genes mutations by HRM analysis. Materials and Methods: 95 clinical Mycobacterium tuberculosis isolates was selected for evaluation by HRM. DNA extracting of isolates and HRM analysis in presence of a single dye was performed and PCR amplification were sequenced from the katG, rpoB, inhA genes. Results: A set of 20 (21/05%) INH-resistence strains and 12 (12/63%) RMP-resistence strains were found to have a mutation in analysis katG gene or inhA locus and rpoB gene. Our detection shows that the most frequency mutation pattern was at 315 codon and codon 279. A nucleonic change was display which is related with INH resistance from 15th C to T in the locus in the rpoB gene, codons that had point mutation were 531 and 545 codons. Conclusion: It is concluded that High Resolution Melting Analysis is a rapid and sensitive method when compared to other molecular methods for detection of drug resistance in Mycobacterium tuberculosis which could be used for screening individual isolates when drug resistence is doubtful.