Molecular detection of Mycobacterium tuberculosis sensitivity to rifampicin and isoniazid in South Gondar Zone, northwest Ethiopia

Abstract

Background Drug resistant tuberculosis (TB) has become a persistent health threat in Ethiopia. In this respect, baseline data are scarce in many parts of high TB burden regions including the different zones of Ethiopia. Methods A total of 111 culture positive M. tuberculosis isolates were recovered from TB patients and identified using region of difference (RD) 9 based polymerase chain reaction (PCR) and spoligotyping. Thereafter, their drug sensitivities to Rifampicin (RIF) and Isoniazid (INH) were evaluated using GenoType MTBDR plus assay . Results The result showed that 18.0% (20/111) of the isolates were resistant to either RIF or INH. Furthermore, 16.7 and 23.8% of the isolates from new and retreatment cases were resistant to any of the two anti-TB drugs, respectively. Multi-drug resistant (MDR) TB was detected on 1.8% (2/111) of all cases. Significantly higher frequencies of any drug resistance were observed among Euro-American (EA) major lineage (χ 2 : 9.67; p = 0.046). Conclusion Considerably high proportion of drug resistant M. tuberculosis strains was detected which could suggest a need for an increased effort to strengthen TB control program in the study area.

Molecular detection of multidrug resistance pattern and associated gene mutations in M. tuberculosis isolates from newly diagnosed pulmonary tuberculosis patients in Addis Ababa, Ethiopia

“…From the tested isolates 93.2% were fully susceptible to both INH and RIF, and 6.8% of the isolates were resistant to at least one of the tested anti-TB drugs. This is relatively lower than previous reports from different parts of the country [ 8 , 9 ]. In a similar manner lower level of INH and RIF resistance was reported from drug naïve TB patients in East Africa [ 20 , 21 ].…”

“…Likewise, a study conducted by Alelign et al reported the existence of a high proportion of drug-resistant M . tuberculosis strains from South Gondar Zone, northwest Ethiopia [ 9 ]. All these studies emphasized the significance of the drug resistance-conferring gene mutations in M .…”

Evaluation of the frequency of resistance to 2 drugs (Isoniazid and Rifampin) by molecular investigation and it's risk factors in new cases of smear positive pulmonary tuberculosis in health centers under the cover of Jundishapur University of Medical Sciences in 2017

“…Many studies have shown that more than 95% of rifampin resistance is because of point mutations in the rpoB gene (the RNA polymerase beta subunit encoding gene). [ 4 ] The most frequent mutations related to rifampin resistance in mycobacterium tuberculosis are replacements at codons 531, 526, and 516 in the rpoB gene, respectively. Mutations in these three codons are the factor for 70 to 95% of resistance to rifampin.…”

“…Mutations in these three codons are the factor for 70 to 95% of resistance to rifampin. [ 4 ] Isoniazid is another effective drug in TB treatment. Isoniazid resistance happens due to mutations in several genes, the most important of which are inhA and katG.…”

“…Currently, according to the our country protocol, antibiotic susceptibility testing is not done for all patients prior to treatment and resistance is diagnosed when the clinical response to first-line therapies is not occurred and the patient's sputum smear is still positive after the 5 months treatment. [ 4 ] The goal of our study was to evaluation of the frequency of resistance to 2 drugs (Isoniazid and Rifampin) by molecular investigation and it's risk factors in new cases of smear positive pulmonary tuberculosis.…”