scholarly journals Drug Susceptibility Profile of Mycobacterium tuberculosis Isolated from Patients Visiting National Tuberculosis Centre, Nepal

2018 ◽  
Vol 5 ◽  
pp. 63-68
Author(s):  
S. Dahal ◽  
M.R. Banjara ◽  
D. Khadka ◽  
G. Ghimire ◽  
S. Sharma

Objectives: The objective of this study was to assess drug susceptibility pattern of Mycobacterium tuberculosis (MTB). Methods: This cross-sectional study was carried out among 145 clinically suspected and previously treated pulmonary tuberculosis patients visiting National Tuberculosis Centre, Bhaktapur, Nepal. After obtaining written informed consent, questionnaire was administered and sputum samples were collected from each patient. Each sample was subjected to Ziehl-Neelsen (ZN) staining and cultured on Lowenstein Jensen (LJ) medium at 37ºC for 8 weeks. MTB isolates were identified by growth rate and colony morphology, confirmed by biochemical tests and drug susceptibility testing (DST) of identified isolates was performed by proportion method. Results: A total of 49.7% (n=72) sputum samples were positive for MTB by culture and 46.9% (n=68) were positive by ZN staining. Among culture positive isolates of MTB (n= 72), 25% (n=18) were resistant to at least one drug. The prevalence of multi drug resistant tuberculosis (MDR-TB) was 15.3% (n=11) of which 5.56% (n=4) were resistant to rifampicin (RIF) only, 1.39% (n= 1) were resistant to isoniazid (INH) only. Out of 18 resistant isolates, 61.1% (n=11) were resistant to both RIF and INH, 21.43% (n=3) resistant to INH were susceptible to RIF and 26.67% (n=4) resistant to RIF were susceptible to INH. Smoking (P=0.001) and coughing (P=0.009) were statistically significant with isolation of MTB. Conclusion: Since the prevalence of MDR-TB was high, MDR-TB strains should be identified in order to initiate second line treatment.

Author(s):  
Aarthi Sridhar ◽  
Anjana Gopi ◽  
Abhilasha Dalal ◽  
Divya Ravi

To compare the sensitivity of 2 microscopic methods for the diagnosis of Mycobacterium tuberculosis (M.tb) along with culture and drug susceptibility testing to first line drugs.: The cross-sectional study comprises 200 suspected cases of pulmonary tuberculosis both clinically and radiologically in KIMS, Bangalore over a period of 2 years. Samples (sputum/BAL fluid) were collected, processed and stained by Ziehl Neelson (ZN) and Fluorescent methods. Culture and drug susceptibilty testing was done for Streptomycin, Isoniazid, Rifampicin and Ethambutol by Mycobacterium growth indicator tube (MGIT) method after decontamination.Fischer’s test : 1. Out of 200 samples: 1.120 were male and 80 were female; 2. 18 were positive by Ziehl Neelson, 21 by Fluorescent and 28 by culture; 3. Majority of the patients belonged to age group 41-50 years (23%); 4. InMGIT, 26 were M.tb and 2 were Non-tubercular mycobacteria; 5. Out of 26 M.tb isolates, 4 were resistant to streptomycin, 6 to isoniazid, 2 to rifampicin and 9 to ethambutol.1. The sensitivity of Fluorescent staining (64.28%) is higher than that of Ziehl-Neelson (51.7%); 2. In MGIT, 26 were M.tb and 2 were Non tubercular mycobacteria; 3. 2 were Multi-drug resistant- tuberculosis (MDR-TB) This study made us aware of the need for prompt detection, identification and appropriate treatment of Tuberculosis due to the rising incidence of MDR-TB.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Akaninyene Otu ◽  
Victor Umoh ◽  
Abdulrazak Habib ◽  
Soter Ameh ◽  
Lovett Lawson ◽  
...  

Background. This study aimed to determine the pattern of drug susceptibility to first-line drugs among pulmonary TB patients in two hospitals in Calabar, Nigeria.Methods. This was a descriptive cross-sectional study carried out between February 2011 and April 2012. Sputum samples from consecutive TB patients in Calabar were subjected to culture on Lowenstein-Jensen (LJ) slopes followed by drug susceptibility testing (DST). The DST was performed on LJ medium by the proportion method.Results. Forty-two of the 100Mycobacterium tuberculosisstrains were found to be resistant to at least one drug. Resistance to only one drug (monoresistance) was found in 17 patients. No strains with monoresistance to rifampicin were found. Resistance to two drugs was found in 22 patients, while one patient was resistant to both three and four drugs. MDR TB was seen in 4% (4/100). The independent variables of HIV serology and sex were not significantly associated with resistance (P>0.05).Conclusion. There was a high prevalence of anti-TB drug resistance in Calabar.


Author(s):  
A. Nikmawati ◽  
Windarwati Windarwati ◽  
Hardjoeno Hardjoeno

Patients infected with resistant Mycobacterium tuberculosis strain will be very difficult to cure by standard treatment. To evaluatethe drug resistance of Mycobacterium tuberculosis. A Cross sectional study was performed from January until July 2005. Samples wereobtained from sputum of the suspect tuberculosis. All samples were cultured in Lowenstein-Jensen Media and followed by sensitivity testaccording to resistance ratio method. Of 236 samples, there were 30% positive cultures. The percentage of mono-resistance to Isoniazidwas 70%, to Rifampicin 64.3%, to Ethambutol 62.8% and Streptomycin 64.3%. The percentage of Multi Drug Resistant Tuberculosis(MDR-TB) was 20–40% and the percentage of poly-resistant (Ethambutol and Streptomycin) was 47.1%. The percentage of suspecttuberculosis with positive culture was 30%. There were also found high percentage of mono-resistant, poly-resistant and MDR-TB.


Author(s):  
Willy Ssengooba ◽  
Jean de Dieu Iragena ◽  
Kevin Komakech ◽  
Iginitius Okello ◽  
Joanitah Nalunjogi ◽  
...  

Abstract Background The Global Laboratory Initiative (GLI) guidelines recommend to repeat GeneXpertMTB/RIF (XpertMTB/RIF) in patients with a low-pretest probability of rifampicin-resistance (RR). Design/Methods In a cross-sectional study using results of sputum specimens collected from participants screened for the STREAM 2 trial. We recruited all patients with XpertMTB/RIF RR-TB detected who were referred for RR/MDR-TB treatment initiation at Mulago National Referral Hospital, Kampala, between September 2017 and October 2019. At baseline, smear microscopy, repeat XpertMTB/RIF, Xpert Ultra and MTBDRplus assays were done on sputum specimens. Culture-based drug-susceptibility testing (DST) were done on discordant specimens. We analysed the prevalence and factors associated with discordance between initial and repeat XpertMTB/RIF RR and false XpertMTB/RIF RR. False XpertMTB/RIF RR was defined as no RR detected by any of Xpert Ultra, LPA or culture DST (reference comparator). Results A total of 126/130 patients had repeat XpertMTB/RIF results of which, 97 (77.0%) had M. tuberculosis detected of whom, 81 (83.5%) had RR detected, and 1 (1.0%) had RR indeterminate. The prevalence of discordant XpertMTB/RIF RR was 15/96 (15.6%) whereas false XpertMTB/RIF RR prevalence was 10/96 (10.4%). Low bacillary load sputum specimens were more likely to have discordant XpertMTB/RIF RR and false XpertMTB/RIF RR results, aOR (p-value: 95%CI), 0.04 (0.01; 0.00-0.37) and 0.02 (0.01; 0.01-0.35) respectively. Conclusion Our findings show a high false-positive rifampicin resistance rate in low TB burden patients, which calls for repeat testing in order to prevent unnecessary prescription of anti MDR-TB therapy.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Anne-Marie Demers ◽  
◽  
Soyeon Kim ◽  
Sara McCallum ◽  
Kathleen Eisenach ◽  
...  

Abstract Background Drug susceptibility testing (DST) patterns of Mycobacterium tuberculosis (MTB) from patients with rifampicin-resistant tuberculosis (RR-TB) or multidrug-resistant TB (MDR-TB; or resistant to rifampicin and isoniazid (INH)), are important to guide preventive therapy for their household contacts (HHCs). Methods As part of a feasibility study done in preparation for an MDR-TB preventive therapy trial in HHCs, smear, Xpert MTB/RIF, Hain MTBDRplus, culture and DST results of index MDR-TB patients were obtained from routine TB programs. A sputum sample was collected at study entry and evaluated by the same tests. Not all tests were performed on all specimens due to variations in test availability. Results Three hundred eight adults with reported RR/MDR-TB were enrolled from 16 participating sites in 8 countries. Their median age was 36 years, and 36% were HIV-infected. Routine testing on all 308 were confirmed as having RR-TB, but only 75% were documented as having MDR-TB. The majority of those not classified as having MDR-TB were because only rifampicin resistance was tested. At study entry (median 59 days after MDR-TB treatment initiation), 280 participants (91%) were able to produce sputum for the study, of whom 147 (53%) still had detectable MTB. All but 2 of these 147 had rifampicin DST done, with resistance detected in 89%. Almost half (47%) of the 147 specimens had INH DST done, with 83% resistance. Therefore, 20% of the 280 study specimens had MDR-TB confirmed. Overall, DST for second-line drugs were available in only 35% of the 308 routine specimens and 15% of 280 study specimens. Conclusions RR-TB was detected in all routine specimens but only 75% had documented MDR-TB, illustrating the need for expanded DST beyond Xpert MTB/RIF to target preventive therapy for HHC.


2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Elina Maharjan ◽  
Narayan Dutt Pant ◽  
Sanjeev Neupane ◽  
Jyoti Amatya ◽  
Bhawana Shrestha

The main aims of this study were to study the patterns of mutations in rpoB, katG, and inhA genes in Mycobacterium tuberculosis strains isolated from patients from Nepal and to evaluate the performance of genotype MTBDRplus assay, taking conventional drug susceptibility testing as gold standard for diagnosis of MDR-TB. A total of 69 Mycobacterium tuberculosis strains isolated from 73 smear positive sputum samples from patients suspected of suffering from multidrug-resistant tuberculosis were used in our study. The drug susceptibility pattern of Mycobacterium tuberculosis isolated from these sputum specimens was determined by using genotype MTBDRplus assay taking conventional drug susceptibility testing as reference. The sensitivity and specificity of the genotype MTBDRplus assay for the detection of MDR-TB were found to be 88.7% and 100%, respectively. 88.7% of the rifampicin resistant isolates had mutations in rpoB gene. Similarly, 79.7% and 9.4% of isoniazid resistant isolates had mutations in katG and inhA genes, respectively. Genotype MTBDRplus assay was found to be very rapid and highly sensitive and specific method for diagnosis of MDR-TB and will be very helpful for early diagnosis of MDR-TB in high tuberculosis burden countries.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261329
Author(s):  
S. M. Mazidur Rahman ◽  
Rumana Nasrin ◽  
Arfatur Rahman ◽  
Shahriar Ahmed ◽  
Razia Khatun ◽  
...  

Background Rapid and early detection of drug susceptibility among multidrug-resistant tuberculosis (MDR-TB) patients could guide the timely initiation of effective treatment and reduce transmission of drug-resistant TB. In the current study, we evaluated the diagnostic performance of GenoType MTBDRsl (MTBDRsl) ver1.0 assay for detection of resistance to ofloxacin (OFL), kanamycin (KAN) and ethambutol (EMB), and additionally the XDR-TB among MDR-TB patients in Bangladesh. Methods The MTBDRsl assay was performed directly on 218 smear-positive sputum specimens collected from MDR-TB patients and the results were compared with the phenotypic drug susceptibility testing (DST) performed on solid Lowenstein-Jensen (L-J) media. We also analyzed the mutation patterns of gyrA, rrs, and embB genes for detection of resistance to OFL, KAN and EMB, respectively. Results The sensitivity and specificity of the MTBDRsl compared to phenotypic L-J DST were 81.8% (95% CI, 69.1–90.9) and 98.8% (95% CI, 95.6–99.8), respectively for OFL (PPV: 95.7% & NPV: 94.1%); 65.1% (95% CI, 57.5–72.2) and 86.7% (95% CI, 73.2–94.9), respectively for EMB (PPV: 94.9% & NPV: 39.4%); and 100% for KAN. The diagnostic accuracy of KAN, OFL and EMB were 100, 94.5 and 69.6%, respectively. Moreover, the sensitivity, specificity and diagnostic accuracy of MtBDRsl for detection of XDR-TB was 100%. The most frequently observed mutations were at codon D94G (46.8%) of gyrA gene, A1401G (83.3%) of rrs gene, and M306V (41.5%) of the embB gene. Conclusion Considering the excellent performance in this study we suggest that MTBDRsl assay can be used as an initial rapid test for detection of KAN and OFL susceptibility, as well as XDR-TB directly from smear-positive sputum specimens of MDR-TB patients in Bangladesh.


2016 ◽  
Vol 10 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Leyla Sahebi ◽  
Khalil Ansarin ◽  
Parviz Mohajeri ◽  
Majid Khalili ◽  
Amir Monfaredan ◽  
...  

Background: Tuberculosis (TB) is the leading cause of morbidity and mortality among chronic infectious diseases. Objective: The goal of this cross-sectional study (2011-2013;2013) was to examine the patterns of TB drug resistance among HIV-negative pulmonary TB patients in regions near the Iranian border. Method: To this end, MTB isolates were harvested from 300 HIV-negative, pulmonary smear-positive TB patients from the northwest and west Iranian border provinces. Isolates were subjected to first and second-line drug susceptibility testing by the 1% proportion method. Demographic and clinical data were provided using a questionnaire and information from patient records. Results were analyzed using SPSS-18. Results: The mean age of the patients was 52.03 years and 54.3% were male. The prevalence of resistance to any TB drug was 13.6% (38 cases). Eleven percent of the new treatment TB group (28 patients) and 40.7% of the retreatment TB group (11 patients) were resistant to all TB drugs. Twelve (4.3%) patients had multidrug-resistant tuberculosis (MDR-TB) (2.38% in the new TB treatment group and 23.1% in the retreatment group). One patient had extensively drug-resistant tuberculosis (XDR-TB). There was a statistically significant relationship between TB drug resistance and smoking (p=0.02) and a history of migration from village to city (p=0.04), also between TB drug resistance and recurrence of TB in patients that had previously received treatment (p<0.001). Conclusion: Knowledge of drug resistance patterns for new and previously treated cases is critical for effective control of MDR-TB in different regions of the country. The burden of MDR-TB in retreatment cases was high. Previous TB treatment was one of the most important mokers and those who had a history of rural to urban migration were at high risk for the occurrence of TB drug resistance.


2019 ◽  
Vol 23 (12) ◽  
pp. 1257-1262 ◽  
Author(s):  
R. J. Chandak ◽  
B. Malhotra ◽  
S. Bhargava ◽  
S. K. Goel ◽  
D. Verma ◽  
...  

SETTING: Patients with presumed multidrug-resistant tuberculosis (MDR-TB) and undergoing MDR-TB treatment from Rajasthan, India.OBJECTIVE: To compare the GenoType® MTBDRsl v.1.0 (MTBDRsl) assay capacity to detect resistance to ofloxacin, amikacin, capreomycin, kanamycin and ethambutol in Mycobacterium tuberculosis with phenotypic drug susceptibility testing (DST) using MGIT™960™ in sputum samples and isolates.DESIGN: Fifty-three smear-positive sputum samples were tested directly by MTBDRsl and 205 MDR-TB isolates were processed using MTBDRsl and DST for five drugs on MGIT960. DNA sequencing was performed in isolates with discordance in the results between the two methods for the gyrA, gyrB and rrs genes.RESULT: Sensitivity and specificity of MTBDRsl was found to be respectively 93.1% and 100% for fluoroquinoline, respectively 75–78% and 100% for aminoglycosides/cyclopeptides, respectively 70% and 92% for ethambutol and respectively 92.3% and 100% for extensively drug-resistant (XDR) TB detection. On sequencing eight discordant isolates for quinolones, mutations were seen in 12.5% of the gyrB gene and among 20 discordant isolates for aminoglycosides/cyclopeptides in the rrs gene in 15% isolates. The turnaround time was 2 days for MTBDRsl vs. 10 days for MGIT960.CONCLUSIONS: MTBDRsl can be used as an initial rapid test for detecting XDR-TB, resistance to quinolones and aminogycosides/cyclopeptides in smear-positive sputum samples.


2019 ◽  
Vol 71 (5) ◽  
pp. 1161-1167 ◽  
Author(s):  
Maunank Shah ◽  
Sonia Paradis ◽  
Joshua Betz ◽  
Natalie Beylis ◽  
Renu Bharadwaj ◽  
...  

Abstract Background Tuberculosis (TB) control is hindered by absence of rapid tests to identify Mycobacterium tuberculosis (MTB) and detect isoniazid (INH) and rifampin (RIF) resistance. We evaluated the accuracy of the BD MAX multidrug-resistant (MDR)-TB assay (BD MAX) in South Africa, Uganda, India, and Peru. Methods Outpatient adults with signs/symptoms of pulmonary TB were prospectively enrolled. Sputum smear microscopy and BD MAX were performed on a single raw sputum, which was then processed for culture and phenotypic drug susceptibility testing (DST), BD MAX, and Xpert MTB/RIF (Xpert). Results 1053 participants with presumptive TB were enrolled (47% female; 32% with human immunodeficiency virus). In patients with confirmed TB, BD MAX sensitivity was 93% (262/282 [95% CI, 89–95%]); specificity was 97% (593/610 [96–98%]) among participants with negative cultures on raw sputa. BD MAX sensitivity was 100% (175/175 [98–100%]) for smear-positive samples (fluorescence microscopy), and 81% (87/107 [73–88%]) in smear-negative samples. Among participants with both BD MAX and Xpert, sensitivity was 91% (249/274 [87–94%]) for BD MAX and 90% (246/274 [86–93%]) for Xpert on processed sputa. Sensitivity and specificity for RIF resistance compared with phenotypic DST were 90% (9/10 [60–98%]) and 95% (211/222 [91–97%]), respectively. Sensitivity and specificity for detection of INH resistance were 82% (22/27 [63–92%]) and 100% (205/205 [98–100%]), respectively. Conclusions The BD MAX MDR-TB assay had high sensitivity and specificity for detection of MTB and RIF and INH drug resistance and may be an important tool for rapid detection of TB and MDR-TB globally.


Sign in / Sign up

Export Citation Format

Share Document