scholarly journals Recent Advances in the Diagnosis of Tuberculosis

2013 ◽  
Vol 47 (4) ◽  
pp. 181-187 ◽  
Author(s):  
Kapil Goyal ◽  
Kusum Sharma ◽  
Suma B Appannanavar
Keyword(s):  
Disease Transmission ◽  
Extrapulmonary Tuberculosis ◽  
Drug Susceptibility ◽  
Drug Susceptibility Testing ◽  
Molecular Techniques ◽  
Timely Initiation ◽  
Recent Advances ◽  
Lowenstein Jensen ◽  
Low Sensitivity ◽  
Diagnostic Microbiology

ABSTRACT Tuberculosis is an important health problem requiring early diagnosis for timely initiation of therapy and control of disease transmission. Though, conventional techniques, such as detection of acid fast bacilli by Ziehl-Neelsen staining, are very economical, yet have a low sensitivity. Isolation of mycobacteria by culture on Lowenstein Jensen media, considered to be the gold standard, is not only time consuming but has a low sensitivity, especially in extrapulmonary tuberculosis. Recent advances in molecular techniques have revolutionized the diagnostic microbiology. Various new modalities in the diagnosis of tuberculosis, like LED microscopy, microscopically observed drug susceptibility testing (MODS), antigen detection tests along with various molecular methods, like loop mediated isothermal amplification (LAMP), multiplex PCR and Xpert MTB/RIF, are discussed in the present review. How to cite this article Sharma K, Appannanavar SB, Goyal K, Sharma A. Recent Advances in the Diagnosis of Tuberculosis. J Postgrad Med Edu Res 2013;47(4):181-187.

scholarly journals Performance of GenoType MTBDRsl assay for detection of second-line drugs and ethambutol resistance directly from sputum specimens of MDR-TB patients in Bangladesh

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261329
Author(s):  
S. M. Mazidur Rahman ◽  
Rumana Nasrin ◽  
Arfatur Rahman ◽  
Shahriar Ahmed ◽  
Razia Khatun ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Rapid Test ◽  
Drug Susceptibility ◽  
Multidrug Resistant ◽  
Drug Susceptibility Testing ◽  
Timely Initiation ◽  
Resistant Tuberculosis ◽  
Mdr Tb ◽  
Lowenstein Jensen ◽  
Sensitivity Specificity

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.

scholarly journals Concurrent evaluation of microscopic observation of drug susceptibility assay for pulmonary and extrapulmonary tuberculosis

2017 ◽  
Vol 9 (02) ◽  
pp. 089-094
Author(s):  
Sonali Sudhir Zadbuke ◽  
Reena Set ◽  
Nishat Khan ◽  
Jayanthi Shastri
Keyword(s):  
Microscopic Observation ◽  
Extrapulmonary Tuberculosis ◽  
Drug Susceptibility ◽  
Multidrug Resistant ◽  
Drug Susceptibility Testing ◽  
Solid Media ◽  
Mdr Tb ◽  
Lowenstein Jensen ◽  
Proportion Method ◽  
Time To Detection

Abstract BACKGROUND: Methods for detection and drug susceptibility of tuberculosis (TB) with solid media are inexpensive but slow and laborious. Rapid methods to diagnose TB and multidrug-resistant TB (MDR-TB) are a global priority for TB control. OBJECTIVES: A study was performed to compare the sensitivity of detection of mycobacterial growth and time of culture positivity by microscopic observation of drug susceptibility (MODS) assay with that of Lowenstein–Jensen (LJ) culture in pulmonary and extrapulmonary TB and to evaluate the concordance of the susceptibilities to isoniazid (INH) and rifampicin (RIF) by MODS and proportion method on LJ. MATERIALS AND METHODS: A prospective, laboratory-based study was conducted on a total of 300 samples from suspected cases of pulmonary and extrapulmonary TB. Samples were inoculated on LJ medium as per the standard guidelines and MODS assay was performed. RESULTS: Sensitivity of MODS assay was 80% and 83.3% and specificity was 92.9% and 83.3% for pulmonary and extrapulmonary samples, respectively. Difference between mean time to detection of Mycobacterium TB (MTB) by LJ medium and MODS was statistically significant, with MODS being faster. drug susceptibility testing (DST) by MODS when compared to economic variant of proportion method was 87.87% for RIF, 90.9% for INH, and 96.96% for MDR-TB detection. CONCLUSIONS: MODS assay provides rapid, safe, and sensitive detection of TB faster than the existing gold standard. It is extremely promising in effectively diagnosing MDR-TB.

scholarly journals Predictive value of direct nitrate reductase assay and its clinical performance in the detection of multi- and extensively drug-resistant tuberculosis

2014 ◽  
Vol 63 (4) ◽  
pp. 522-527 ◽  
Author(s):  
Belén R. Imperiale ◽  
Nora S. Morcillo ◽  
Juan C. Palomino ◽  
Peter Vandamme ◽  
Anandi Martin
Keyword(s):  
Nitrate Reductase ◽  
Clinical Performance ◽  
Low Cost ◽  
Simultaneous Detection ◽  
Drug Susceptibility ◽  
Drug Susceptibility Testing ◽  
Conventional Culture ◽  
Nitrate Reductase Assay ◽  
Lowenstein Jensen ◽  
Set Up

Conventional culture and drug susceptibility testing (DST) methods for Mycobacterium tuberculosis are laborious and time consuming. For this reason alternative rapid culture and DST techniques are urgently needed to shorten the time for drug-resistance detection. A total of 222 smear-positive sputum samples were evaluated by the direct nitrate reductase assay (D-NRA) on Lowenstein–Jensen medium, for the rapid and simultaneous detection of resistance to isoniazid, rifampicin, kanamycin and ofloxacin. p-Nitrobenzoic acid was also included for identification of the M. tuberculosis complex. Results were compared with the BACTEC MGIT 960 as gold standard. The general performance of the D-NRA was very good, reaching a global value of 97 %. D-NRA had a turn-around time of 16.9 days to obtain results while that of the indirect MGIT 960 system was 29 days. D-NRA is a low-cost technology, easy to set up in clinical laboratories and suitable to be used for DST of M. tuberculosis in all smear-positive samples.

scholarly journals Comparison of MGIT960 with Lowenstein-Jensen Method for Mycobacteria Detection in Pulmonary Tuberculosis and Drug Susceptibility Testing

2021 ◽  
Vol 4 (6) ◽  
pp. 12-17
Author(s):  
Kalpana Thangavelu ◽  
Imola Jamir ◽  
Ellappan Kalaiarasan ◽  
Pallam Gopichand ◽  
Krishnakumariamma Krishnapriya ◽  
...  
Keyword(s):  
Pulmonary Tuberculosis ◽  
Susceptibility Testing ◽  
Drug Susceptibility ◽  
Drug Susceptibility Testing ◽  
Lowenstein Jensen

scholarly journals Non-pncAGene-Mutated but Pyrazinamide-Resistant Mycobacterium tuberculosis: Why Is That?

2017 ◽  
Vol 55 (6) ◽  
pp. 1920-1927 ◽  
Author(s):  
Jim Werngren ◽  
Erik Alm ◽  
Mikael Mansjö
Keyword(s):  
Susceptibility Testing ◽  
Gene Mutations ◽  
Drug Susceptibility ◽  
Multidrug Resistant ◽  
Drug Susceptibility Testing ◽  
Molecular Techniques ◽  
Content Type ◽  
Resistant Strains ◽  
Clear Majority

ABSTRACTPyrazinamide (PZA) is a key component for the effective treatment of drug-susceptible and PZA-susceptible multidrug-resistant (MDRPZA-S) tuberculosis (TB).pncAgene mutations are usually detected in a clear majority (>90%) of PZA-resistant strains but obviously not in all. Rapid and reliable PZA drug susceptibility testing (DST) is critical whenever PZA is to be used in a treatment regimen, not least for the treatment of MDRPZA-STB. In this study, we selected 26 PZA-resistant isolates reported to carry a wild-typepncAgene. To confirm resistance, susceptibility testing was repeated using 100 mg/liter and 200 mg/liter PZA for all the 26 isolates and Sanger sequencing was repeated on the 18 isolates that remained PZA resistant. Apart from the eight isolates initially misclassified as PZA resistant, the retests identified three factors responsible for the phenotype-genotype discrepancy:panDorrpsAmutations identified by whole-genome sequencing (WGS) (n= 7), heteroresistance (n= 8), and mixed populations withMycobacterium avium(n= 3). Additionally, we performed WGS on 400 PZA-susceptible isolates and 15 consecutive MDRPZA-Rclinical isolates. Of the 400 PZA-susceptible isolates, only 1 harbored a nonsynonymouspncAmutation (Thr87Met), whereas a nonsynonymousrpsAmutation was found in 17 isolates. None of these isolates carried a nonsynonymouspanDmutation, while all 15 of the MDRPZA-Risolates harbored a nonsynonymouspncAmutation. Our findings indicate that it is necessary to consider the occurrence ofpanDmutations in PZA-resistant isolates, as well as heteroresistance, for the development and evaluation of new molecular techniques to ensure high-quality DST performance. The identification of nonsynonymousrpsAmutations in both PZA-susceptible and PZA-resistant isolates also implies that further studies are needed in order to determine the role ofrpsAin PZA resistance.

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
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Drug Susceptibility ◽  
Cross Sectional Study ◽  
Drug Susceptibility Testing ◽  
Biochemical Tests ◽  
Cross Sectional ◽  
Resistant Tuberculosis ◽  
National Tuberculosis ◽  
Mdr Tb ◽  
Lowenstein Jensen

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.

scholarly journals Effect of Piper nigrum (Linn.) seeds extract and second line anti-tuberculosis drugs on a few Mycobacterium tuberculosis strains

2021 ◽  
Vol 13 (1) ◽  
pp. 402-406
Author(s):  
G. V. Zodape ◽  
S. N. Dharmashale ◽  
V. S. Gaikwad
Keyword(s):  
Mycobacterium Tuberculosis ◽  
In Vitro Study ◽  
Ethanolic Extract ◽  
Drug Susceptibility ◽  
Drug Susceptibility Testing ◽  
Piper Nigrum ◽  
Amino Salicylic Acid ◽  
Lowenstein Jensen ◽  
Proportion Method

Piper nigrum (Linn.) belonging to the family Piperaceae have been reported for its multitudinous medicinal values. The present study was undertaken to examine the direct effect of Ethionamide (ETH), Para amino salicylic acid (PAS), ethanolic extracts of P. nigrum on Mycobacterium tuberculosis (MTB) strain H37Rv and Multi drug-resistant (MDR)-strains-12, 19 and 21. The proportion method was used to detect the anti-mycobacterial drug susceptibility testing for mycobacteria using Lowenstein Jensen (LJ) medium. It was found that P. nigrum does not interfere with single or in the combination of both ETH and PAS showing the bioenhancer activity. In vitro study of ethanolic extract of P. nigrum observed that the extract inhibited the growth of H37Rv strains and MDR strains-12, MDR strains 19, and MDR strains 21. The present results will pave new avenues to find a new medicine that possesses P. nigrum alone or in combination with drugs to combat MDR-strains controlling tuberculosis.

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