Spoligotyping and Drug Sensitivity of Mycobacterium tuberculosis isolated from Pulmonary Tuberculosis Patients in the Arsi Zone of South Eastern Ethiopia

2019 ◽  
Author(s):  
Belete Haile Nega ◽  
Ketema Tafess ◽  
Aboma Zewude ◽  
Bazezew Yenew ◽  
Gilman SIU ◽  
...  

Abstract Background Tuberculosis (TB) is one of the leading disease causing morbidity and mortality in different zones of Ethiopia including the Arsi Zone. However, little or no scientific information is available on the strains of Mycobacterium tuberculosis and their drug sensitivity profiles in this Zone. This study was conducted to identify the strains of M. tuberculosis and evaluate their drug sensitivity profiles. Methodology A total of 111 clinical isolates of M. tuberculosis from patients with pulmonary TB in the Arsi Zone were used for this study. The region of difference 9 (RD 9)-based polymerase chain reaction (PCR)and spoligotyping methods were used for speciation and strain identification of Mycobacterium tuberculosis respectively.The spoligotyping patterns were compared with the international SpolDB4 (SITVIT) and Run TB-Lineage used for the identification of lineages. The phenotypic drug susceptibility patterns were confirmed by BD BactecMGIT 960 SIRE test and GenoType MTBDRplus line probe assays were used for the detection the drug resistance-conferring mutations of the isolates. Result The spoligotype patterns of 83% (92/111) of the isolates were interpretable and 56 different patterns were identified. Twenty-two of these patterns were shared types while the remaining 34 were orphans. The predominant shared types were spoligotype international type (SIT) 149 and SIT53, each consisting of 12 and 11 isolates, respectively. The lineages identified were Euro-American, East-African-Indian, Mycobacterium-africanum, and Indo-Oceanic in descending order. Phenotypically, 17.2% of the 64 tested isolates were resistant to any of the four first-line drugs while 3.1% of them were multi-drug resistant (MDR). Higher (6.2%) monoresistance was observed to Streptomycin followed by Isoniazid (3.1%) while no resistance was observed either to Rifampicin or to Ethambutol. Genotypically, five (5.4%) isolates were resistant to Isoniazid and mutated at codon S315T1 of katG. On the other hand, only 1.1% of the isolates was resistant to Rifampicin and mutated at codon S531L of rpoB gene. Conclusion The proportion of orphan strains isolated in this study was high, which could suggest the presence of new strains in the Zone. Moreover, the study showed relatively high percentage of mono-resistance to any four first-line drugs warranting for the need to strengthen the control efforts.

2019 ◽  
Vol 3 (2) ◽  
pp. 35
Author(s):  
Titiek Sulistyowati ◽  
Deby Kusumaningrum ◽  
Eko Budi Koendhori ◽  
Ni Made Mertaniasih

Background: Tuberculosis continues one of the major challenges to global health. Mycobacterium tuberculosis complex can affect any organ other than the lung parenchyma, include central nervous system. The mortality rate of tuberculous meningitis (TBM) are high worldwide with up to half of survivors suffering irreversible sequelae. Diagnosis of TBM is difficult due to paucibacillary, various clinical manifestation, and invasive procedure to appropriate specimens. Objective: The objectiveis to study the positivity rate of microbiological laboratory diagnosis and its drug sensitivity patterns of TBM patients in Dr. Soetomo Hospital Surabaya during October 2015 until September 2016. Methods: Specimens were cerebrospinal fluids. Identification and drug anti TB sensitivity test were done by BACTEC MGIT 960 system in Clinical Microbiology Laboratory Dr. Soetomo Hospital Surabaya. Result: Most patients with TBM were women (54.29%). Based on age groups, most dominant was adult population (65.71%). Proportion percentage of positive M. tuberculosis complex among 180 specimens were 19.44%. First line anti TB drug sensitivity pattern of 35 isolates were 1 monoresistant, 1 poly-resistant, no multiple drug resistant (MDR), and 33 pan-susceptible. Conclusion: Positivity rate of Mycobacterium tuberculosis complex laboratory diagnosis from TBM suspect patients were low. There was no MDR TB in this study, but mono-resistant and poly-resistant. Microbiological diagnosis was important to give information of active disease and drug sensitivity pattern. Resistance to first line anti TB drugs is alarming to properly manage TBM patients.


Author(s):  
K. B. Arun ◽  
Aravind Madhavan ◽  
Billu Abraham ◽  
M. Balaji ◽  
K. C. Sivakumar ◽  
...  

AbstractIsoniazid (INH), one of the first-line drugs used for the treatment of tuberculosis, is a pro-drug which is converted into its active form by the intracellular KatG enzyme of Mycobacterium tuberculosis. The activated drug hinders cell wall biosynthesis by inhibiting InhA protein. INH resistant strains of M. tuberculosis usually have mutations in katG, inhA, ahpC, kasA, and ndh genes. However, INH resistant strains which do not have mutations in any of these genes are reported, suggesting that these strains may adopt some other mechanism to become resistant to INH. In the present study we characterized Rv2170, a putative acetyltransferase in M. tuberculosis, to elucidate its role in inactivating isoniazid. The purified recombinant protein was able to catalyze transfer of acetyl group to INH from acetyl CoA. HPLC and LC-MS analyses showed that following acetylation by Rv2170, INH is broken down into isonicotinic acid and acetylhydrazine. Drug susceptibility assay and confocal analysis showed that M. smegmatis, which is susceptible to INH, is not inhibited by INH acetylated with Rv2170. Recombinant M. smegmatis and M. tuberculosis H37Ra overexpressing Rv2170 were found to be resistant to INH at minimum inhibitory concentrations that inhibited wildtype strains. In addition, intracellular M. tuberculosis H37Ra overexpressing Rv2170 survived better in macrophages when treated with INH. Our results strongly indicate that Rv2170 acetylates INH, and this could be one of the strategies adopted by at least some M. tuberculosis strains to overcome INH toxicity.


2011 ◽  
Vol 6 (01) ◽  
pp. 33-39 ◽  
Author(s):  
Perpetual Wangui Ndung'u ◽  
Samuel Kariuki ◽  
Zipporah Ng'ang'a ◽  
Gunturu Revathi

Introduction: In Kenya, which ranks thirteenth of 27 high tuberculosis burden countries, diagnosis is based on Ziehl-Neelsen staining alone and patients are treated without information on sensitivity patterns. This study aimed to determine resistance patterns of Mycobacterium tuberculosis isolated from pulmonary samples.Methodology: Pulmonary tuberculosis patients in Nairobi were randomly sampled after informed consent and recruited into the study using a structured questionnaire. Specimens were cultured in liquid and solid media, and drug susceptibility tests were performed for first-line drugs including (isoniazid, rifampin, streptomycin, ethambutol and pyrazinamide). Results: Eighty-six (30%) of 286 isolates were resistant to at least one of five antibiotics tested. Thirty-seven (30.2%) isolates were resistant to isoniazid; 15 (11.6%) to streptomycin; 13 (4.5%) to ethambutol; four (1.4%) to rifampin ; and 30 (10.4%) to pyrazinamide. Double resistance was seen as follows: four (1.4%) isolates were resistant to both isoniazid and pyrazinamide; four (1.4%) to streptomycin and isoniazid; and one (0.3%) to rifampin and streptomycin. Two isolates (0.7%) were multidrug resistant, and one was triple resistant with an additional resistance to ethambutol. Results also showed 88.7% of patients were below the age of 40 years, while 26.3% were HIV positive. The majority of the patients (66.5%) were unemployed or self-employed in small businesses, with 79.4% earning less than 100 USD per month.Conclusion: The high resistance observed in isoniazid, which is a first-line drug, could result in an increase in multidrug resistance unless control programs are strengthened. Poverty should be addressed to reduce infection rates.


2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199759
Author(s):  
Mei-Chun Zeng ◽  
Qing-Jun Jia ◽  
Lei-Ming Tang

Objective The aim was to analyze genetic mutations in the rpoB gene of rifampin-resistant Mycobacterium tuberculosis isolates (RIFR-MTB) from Zhejiang, China. Methods We prospectively analyzed RIFR-associated mutations in 13 rural areas of Zhejiang. Isolates were subjected to species identification, phenotype drug susceptibility testing (DST), DNA extraction, and rpoB gene sequencing. Results A total of 103 RIFR isolates were identified by DST (22 RIFR only, 14 poly-drug resistant, 49 multidrug resistant, 13 pre-extensively drug resistant [pre-XDR], and 5 extensively drug resistant [XDR]) from 2152 culture-positive sputum specimens. Gene sequencing of rpoB showed that the most frequent mutation was S450L (37.86%, 39/103); mutations P280L, E521K, and D595Y were outside the rifampicin resistance-determining region (RRDR) but may be associated with RIFR. Mutations associated with poly-drug resistant, pre-XDR, and XDR TB were mainly located at codon 445 or 450 in the RRDR. Conclusions The frequency of rpoB RRDR mutation in Zhejiang is high. Further studies are needed to clarify the relationships between RIFR and the TTC insertion at codon 433 in the RRDR and the P280L and D595Y mutations outside the RRDR.


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