Comparative Study of GeneXpert MTB/RIF Assay and Multiplex PCR Assay for Direct Detection of Mycobacterium tuberculosis in Suspected Pulmonary Tuberculosis Patients

Abstract

Pulmonary tuberculosis (PTB) is one of the major infectious diseases in developing countries. The objective of this study was to compare rapid diagnostics technique, GeneXpert MTB/RIF (GeneXpert) and Multiplex PCR assay (MPCR) targeting IS6110 segment and mpb64 gene for direct detection of Mycobacterium tuberculosis (MTB) in suspected PTB patients. A cross sectional study was carried among 105 sputum samples from suspected PTB patients to evaluate GeneXpert and Multiplex PCR who visited National Tuberculosis Center, Nepal. The patient's sputum samples were used directly for the GeneXpert whereas DNA extraction by CTAB method was followed to process the sample for MPCR. The sensitivity and specificity of GeneXpert and MPCR in smear positive cases was 78.6, 33.3, and 100.0%, 66.7%, respectively (P = 0.125). However, in smear negative cases sensitivity and specificity of both methods exhibited 90.9, 95.2, and 100.0%, 100.0% respectively (P = 0.625). Finally, the sensitivity and specificity of GeneXpert and MPCR were 82.9, 95.3 and 100.0%, 98.5% respectively, (P = 0.549) in pulmonary cases. Comparatively, we observed higher sensitivity and specificity for MPCR than GeneXpert for both smear positive and negative samples. Thus, we recommend MPCR alongside GeneXpert for the better diagnostic accuracy of PTB in a resource-limited country where tuberculosis is endemic.

Xpert MTB/RIF and Xpert MTB/RIF Ultra for pulmonary tuberculosis and rifampicin resistance in adults

“…We included 70 studies involving 37,237 unselected participants (Adelman 2015; Al‐Darraji 2013; Atwebembeire 2016; Balcells 2012; Balcha 2014; Barmankulova 2015; Bates 2013a; Bjerrum 2016; Boehme 2010; Boehme 2011; Boum 2016; Calligaro 2015; Calligaro 2017; Carriquiry 2012; Chaisson 2014; Chen 2017; Chew 2016; Cowan 2017; Davis 2014; Dorman 2018; Geleta 2015; Hanif 2011; Hanrahan 2013; Hanrahan 2014; Helb 2010; Henostroza 2016; Huang 2015; Huh 2014; Kawkitinarong 2017; Kim CH 2015; Ko 2016; Kurbaniyazova 2017; Kurbatova 2013; Kwak 2013; LaCourse 2016; Lawn 2011; Lippincott 2014; Liu 2017; Luetkemeyer 2016; Mbelele 2017; Mollel 2017; Moussa 2016; Mutingwende 2015; Ngabonziza 2016; Nikam 2014; Nliwasa 2016; Nosova 2013a; O'Donnell 2015; Park 2013; Pinyopornpanish 2015; Rachow 2011; Reddy 2017; Reechaipichitkul 2017; Rice 2017; Safianowska 2012; Sah 2017; Scott 2011; Scott 2017; Shao 2017; Sharma 2015; Shenai 2016…”

“…We limited this analysis to 45 studies that reported results for participants with smear‐positive specimens and smear‐negative specimens within the same study (Balcells 2012; Balcha 2014; Boehme 2010; Boehme 2011; Carriquiry 2012; Chaisson 2014; Chen 2017; Chew 2016; Cowan 2017; Davis 2014; Dorman 2018; Geleta 2015; Hanif 2011; Hanrahan 2013; Hanrahan 2014; Helb 2010; Huang 2015; Huh 2014; Kawkitinarong 2017; Ko 2016; Kurbatova 2013; Kwak 2013; Lawn 2011; Lippincott 2014; Luetkemeyer 2016; Moussa 2016Ngabonziza 2016; Nikam 2014; O'Donnell 2015; Park 2013; Rachow 2011; Reddy 2017; Reechaipichitkul 2017; Rice 2017; Safianowska 2012; Sah 2017; Scott 2011; Shao 2017; Sharma 2015; Shenai 2016; Sohn 2014; Theron 2011; Tsuyuguchi 2017; Zeka 2011; Zmak 2013). For smear‐positive tuberculosis, Xpert MTB/RIF pooled sensitivity was 98% (97% to 98%), considerably higher than the sensitivity of 68% (63% to 73%) for smear‐negative tuberculosis (Table 5).…”

Diagnostic and Therapeutic Strategies for Peritoneal Tuberculosis: A Review

“…In addition to increasing the general sensitivity of the assay, these new targets also have the added benefit of bypassing the high cost of the Xpert assay. In one study comparing the Xpert MTB/RIF assay with multiplex PCR in the detection of TB in suspected pulmonary TB, multiplex PCR had a higher sensitivity and specificity (sensitivity of 100.0% and specificity of 66.7%) than Xpert MTB/RIF (sensitivity of 78.6% and specificity of 33.3%) 52. A number of other studies looking at multiplex PCR in the diagnosis of extrapulmonary TB suggested a pooled sensitivity of roughly 94.5% 53–56.…”

Comparison between the PaxView TB/NTM MPCR-ULFA Kit and Xpert MTB/RIF for Mycobacterium Tuberculosis Detection in Indonesian Clinical Isolates

“…The PaxView TB/NTM MPCR-ULFA Kit showed a higher detection rate of MTB (40.7 percent) than that of the Xpert MTB/RIF (37.9 percent). In the study of another group on the detection of meningitis TB in India, the MPCR sensitivity was 1.7 times higher (87.2 percent /50.5 percent) than that of the Xpert MTB/RIF and 1.2 times higher (100 percent /82.9 percent) for pulmonary detection 12,13 . This may have been due to target gene differences, as the former is IS6110-specific while the latter is rpoB-specific.…”