Discordance between Genexpert, Line Probe Assay and Drug Susceptibility Test in Assessing Drug-Resistant Tuberculosis

Background. This study aims to evaluate GenoType MTBDRplusand GenoType MTBDRslfor their ability to detect drug-resistant tuberculosis in a Chinese population.Methods. We collected 112Mycobacteria tuberculosisstrains from Jiangsu province, China. The conventional DST and line probe assay were used to detect drug resistance to rifampicin (RFP), isoniazid (INH), ofloxacin (OFX), kanamycin (Km), and ethambutol (EMB).Results. The sensitivity and specificity were 100% and 50% for RFP and 86.11% and 47.06% for INH, respectively. The most common mutations observed in MTBDRpluswererpoBWT8 omission + MUT3 presence,katGWT omission + MUT1 presence, andinhAWT1 omission + MUT1 presence. For drug resistance to OFX, Km, and EMB, the sensitivity of MTBDRslwas 94.74%, 62.50%, and 58.82%, respectively, while the specificity was 92.59%, 98.81%, and 91.67%, respectively. The most common mutations weregyrAWT3 omission + MUT3C presence,rrsMUT1 presence,embBWT omission + MUT1B presence, andembBWT omission + MUT1A presence. Sequencing analysis found several uncommon mutations.Conclusion. In combination with DST, application of the GenoType MTBDRplusand GenoType MTBDRslassays might be a useful additional tool to allow for the rapid and safe diagnosis of drug resistance to RFP and OFX.

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RAPID DETECTION OF MULTI DRUG RESISTANCE AMONG MULTI DRUG RESISTANT TUBERCULOSIS SUSPECTS USING LINE PROBE ASSAY

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i1.14341 ◽

2016 ◽

Vol 10 (1) ◽

pp. 131

Author(s):

Sanjeev Saini ◽

Manoj Kumar Dubey ◽

Uma Bhardwaj ◽

M Hanif ◽

Chopra Kk ◽

...

Keyword(s):

Fluorescent Microscopy ◽

Multi Drug Resistance ◽

Sputum Smear ◽

Drug Resistant ◽

Line Probe Assay ◽

Drug Resistant Tuberculosis ◽

Resistant Tuberculosis ◽

Multi Drug Resistant Tuberculosis ◽

Mdr Tb ◽

Probe Assay

ABSTRACTObjective: GenoType MTBDRplus line probe assay (LPA) is developed for performing drug susceptibility testing (DST) for Rifampicin (RIF) andisoniazid in sputum specimens from smear-positive pulmonary tuberculosis (TB) patients and revised national TB control Programme (RNTCP)has endorsed LPA for the diagnosis of multi drug resistant TB (MDR-TB). This study was conducted to assess the potential utility of LPA for MDR-TBpatient management.Methods: MDR-TB suspects under RNTCP PMDT criteria C referred from different districts in Delhi state were included in the study January 2013 toDecember 2014. Sputum specimens found acid-fast bacilli positive by fluorescent microscopy were processed for LPA.Results: Out of 3062 specimens, 2055 (67.1%) MDR-TB suspects were read as positive and specimens from 1007 (32.9%) suspects were read asnegative in sputum smear microscopy. Out of 2019 specimens valid LPA results, 1427 were found to be pan-sensitive, 280 were MDR-TB, 40 were RIFmonoresistant, 183 were Isoniazid (INH) monoresistant, and 89 specimens were found negative for Mycobacterium tuberculosis.Conclusion: Routine use of LPA can substantially reduce the time to diagnosis of RIF and/or INH-resistant TB and can hence potentially enable earliercommencement of appropriate drug therapy and thereby facilitate prevention of further transmission of drug resistant strains.Keywords: Multi drug resistant tuberculosis, Line probe assay, Rifampicin, Isoniazid.

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