Open AccessPrevalence and Distribution of Multidrug-Resistant Mutations in Mycobacterium tuberculosis in Tanzania
Author(s) -
John C. Mgogwe,
Hadija Semvua,
Oliva Safari,
Gibson Kapanda,
Balthazar Nyombi,
Jaffu Chilongola
Publication year - 2019
Publication title -
east africa science
Language(s) - English
Resource type - Journals
eISSN - 2664-1003
pISSN - 2664-0996
DOI - 10.24248/easci.v1.iss1.14
Subject(s) - rpob , inha , rifampicin , mycobacterium tuberculosis , isoniazid , tuberculosis , medicine , gene mutation , multiple drug resistance , genotype , sputum , virology , ethionamide , drug resistance , biology , mutation , genetics , gene , ethambutol , pathology
Background:Molecular identification of mutations resulting inmultidrug-resistant tuberculosis (MDR-TB) is an important approach forimproving understanding of MDR-TB epidemiology and planning forappropriate interventions. We aimed to estimate the prevalence anddistribution of mutations causing MDR-TB as well as determine the genedistribution among patients previously treated for TB. Methods: This was across-sectional, hospital-based study conducted from April 2017 toOctober 2018 at Kibong’oto Infectious Diseases Hospital (KIDH). KIDH isthe national MDR-TB referral hospital. Participants were patientspresumptively diagnosed with MDR-TB and referred to KIDH from districtand regional hospitals across Tanzania. Sputum samples were collectedand analysed using the Xpert MTB/RIF assay, direct sputum smearfluorescence microscopy, culture on Lowenstein-Jensen medium, and lineprobe assay using the GenoType MTBDRplus VER 2.0 system. Demographicinformation and mutation frequencies were reported as counts andpercentages and analysed using descriptive statistics. Results: A total of 208(69.3%) participants had rpoB gene mutationsconferring resistance to only rifampicin; 92 (30.7%) hadrpoB, katG, and inhAmutations conferring resistance to rifampicin and isoniazid;78 (26%) had rpoB and katGmutations conferring resistance to rifampicin and isoniazid;and 14 (4.7%) had rpoB and inhAmutations conferring resistance to rifampicin andisoniazid. Conclusion:The mutation prevalences identified in this studyindicate the most frequent mutations were the S531L mutation of therpoB gene, the S315T1 mutation of thekatG gene, and the S315T mutation in the promoterregion of the inhA gene. To control the emergenceand spread of MDR-TB, drug sensitivity testing must be carried forGeneXpert-confirmed TB patients prior to initiating second-line anti-TBregimens.