Molecular differentiation of multi-drug resistant mycobacterium tuberculosis complex isolated from three provinces in Zambia
type: CreativeWork
description: Multidrug-resistant tuberculosis (MDR-TB) is a disease caused by an acid-fast staining pathogenic bacterium, Mycobacterium tuberculosis that is resistant to at least isoniazid (INH) and rifampicin (RIF), the two most potent TB drugs. Drug-resistant tuberculosis poses a significant problem for successful treatment of tuberculosis (TB). Worldwide, 4.1 percent of new cases and 19 percent of previously treated cases have been estimated to show MDR-TB and in Zambia, 1.8 percent and 2.3 percent MDR TB among new and previously treated cases respectively have been reported. This study was conducted to characterize the isolates of Mycobacterium tuberculosis complex (MTBC) associated with rifampicin (RIF) and isoniazid (INH) drug resistance and to determine the prevalence of mutations attributed to two specific genes (rpoB and katG) and the inhA promoter region which have been linked to resistance against rifampicin and isoniazid. A panel of 40 INH and/or RIF drug resistant clinical isolates of Mycobacterium tuberculosis complex with susceptibility test results from Mycobacteria Growth Indicator Tubes (MGIT) were used. Isolates showing resistance to RIF and INH were analysed by multiplex polymerase chain reaction (PCR) and the amplicons were sequenced using the Big Dye Terminator v3.1 cycle sequencing kit on the ABI Prism 3500xl Genetic Analyser (Life Technologies Corp). All of the analysed isolates were identified to be Mycobacterium tuberculosis. Seventy-five percent (30/40) of these had katG mutations at codon 315, 7.5 percent (3/40) had the katG mutation alone while 2.5 percent (1/40) had mutations in the inhA promoter and rpoB in addition to the katG 315 mutation. KatG S315T mutation and the -18CT inhA mutation accounted for only 2.6 percent (1/39) of the INH-resistant isolates. Of the 40 isolates characterized for rpoB mutations, 39 demonstrated mutations with the most common being S450L (48.7 percent), followed by H445T (20.5 percent). In one phenotypically-RIF resista…
abstract: Multidrug-resistant tuberculosis (MDR-TB) is a disease caused by an acid-fast staining pathogenic bacterium, Mycobacterium tuberculosis that is resistant to at least isoniazid (INH) and rifampicin (RIF), the two most potent TB drugs. Drug-resistant tuberculosis poses a significant problem for successful treatment of tuberculosis (TB). Worldwide, 4.1 percent of new cases and 19 percent of previously treated cases have been estimated to show MDR-TB and in Zambia, 1.8 percent and 2.3 percent MDR TB among new and previously treated cases respectively have been reported. This study was conducted to characterize the isolates of Mycobacterium tuberculosis complex (MTBC) associated with rifampicin (RIF) and isoniazid (INH) drug resistance and to determine the prevalence of mutations attributed to two specific genes (rpoB and katG) and the inhA promoter region which have been linked to resistance against rifampicin and isoniazid. A panel of 40 INH and/or RIF drug resistant clinical isolates of Mycobacterium tuberculosis complex with susceptibility test results from Mycobacteria Growth Indicator Tubes (MGIT) were used. Isolates showing resistance to RIF and INH were analysed by multiplex polymerase chain reaction (PCR) and the amplicons were sequenced using the Big Dye Terminator v3.1 cycle sequencing kit on the ABI Prism 3500xl Genetic Analyser (Life Technologies Corp). All of the analysed isolates were identified to be Mycobacterium tuberculosis. Seventy-five percent (30/40) of these had katG mutations at codon 315, 7.5 percent (3/40) had the katG mutation alone while 2.5 percent (1/40) had mutations in the inhA promoter and rpoB in addition to the katG 315 mutation. KatG S315T mutation and the -18CT inhA mutation accounted for only 2.6 percent (1/39) of the INH-resistant isolates. Of the 40 isolates characterized for rpoB mutations, 39 demonstrated mutations with the most common being S450L (48.7 percent), followed by H445T (20.5 percent). In one phenotypically-RIF resista…
author: Kapona, Otridah
language: en
keywords: Multidrug-resistant tuberculosis--Zambia, Mycobacterium tuberculosis--Zambia
date published: 2019
date modified: 2026-07-27T22:06:08Z
provider: University of Zambia
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: The University of Zambia