Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis

The World Health Organization (WHO) has incorporated various strategies to strengthen tuberculosis (TB) control programmes. The current diagnostic tools for TB detection require different levels of laboratory sophistication due to technical complexities, expertise and biosafety requirements in nu...

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Main Author: Salleh, Nur Eyuni Mohd
Format: Thesis
Language:English
Published: 2022
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Online Access:http://eprints.usm.my/57346/1/NUR%20EYUNI%20BINTI%20MOHD%20SALLEH-FINAL%20THESIS%20P-SKD001416%28R%29%20-24%20pages.pdf
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spelling my-usm-ep.573462023-11-23T06:59:41Z Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis 2022-08 Salleh, Nur Eyuni Mohd QR75-99.5 Bacteria The World Health Organization (WHO) has incorporated various strategies to strengthen tuberculosis (TB) control programmes. The current diagnostic tools for TB detection require different levels of laboratory sophistication due to technical complexities, expertise and biosafety requirements in nucleic acid (NA) based TB testing. Therefore, it is challenging to use NA-based assays in resource-constrained settings. With such limitations, there is a need to develop new approaches that can facilitate point-of-care (POC) diagnostics. Recombinase amplification assay (RPA) is an NA-based amplification platform that requires an optimal heat source for accurate diagnosis of a particular disease in a short time. The method is capable of amplifying specific NA at a single, low and constant temperature with minimal amount of sample preparation. In this study, a rapid assay for the detection of Mycobacterium tuberculosis (Mtb) based on the RPA targeting the B9 sequence was developed. The RPA-based detection of Mtb DNA was achieved within 20 minutes at 39°C. The analytical sensitivity of the test was one pg when tested using purified Mtb genomic DNA. The clinical performance of the RPA was evaluated using 387 sputum samples with the culture method as the gold standard. RPA and microscopy were compared to the gold standard in terms of sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value. The results showed that the sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value of RPA were 97.2% (95% CI: 93.5, 99.0), 92.2% (95% CI: 87.6, 95.2), 91.7% (95% CI: 87.8, 95.6), 97.4% (95% CI: 95.2, 99.7), 7.8% (4.2, 11.4), 2.8% (95% CI:0.4, 5.1), respectively, while microscopy had a sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value of 90.6% (95% CI: 85.4, 94.1), 88.8% (95% CI: 83.7, 92.5), 87.7% (95% CI: 83.0, 92.4), 91.5% (95% CI:87.6, 95.4), 11.2% (95% CI:6.9, 15.4) and 9.4% (95% CI:5.2, 13.6), respectively. RPA was found to be more sensitive and specific compared to microscopy, suggesting that the method has the potential to be used as a point-of-care (POC) TB diagnostic tool. 2022-08 Thesis http://eprints.usm.my/57346/ http://eprints.usm.my/57346/1/NUR%20EYUNI%20BINTI%20MOHD%20SALLEH-FINAL%20THESIS%20P-SKD001416%28R%29%20-24%20pages.pdf application/pdf en public phd doctoral Universiti Sains Malaysia Pusat Pengajian Sains Kesihatan
institution Universiti Sains Malaysia
collection USM Institutional Repository
language English
topic QR75-99.5 Bacteria
spellingShingle QR75-99.5 Bacteria
Salleh, Nur Eyuni Mohd
Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
description The World Health Organization (WHO) has incorporated various strategies to strengthen tuberculosis (TB) control programmes. The current diagnostic tools for TB detection require different levels of laboratory sophistication due to technical complexities, expertise and biosafety requirements in nucleic acid (NA) based TB testing. Therefore, it is challenging to use NA-based assays in resource-constrained settings. With such limitations, there is a need to develop new approaches that can facilitate point-of-care (POC) diagnostics. Recombinase amplification assay (RPA) is an NA-based amplification platform that requires an optimal heat source for accurate diagnosis of a particular disease in a short time. The method is capable of amplifying specific NA at a single, low and constant temperature with minimal amount of sample preparation. In this study, a rapid assay for the detection of Mycobacterium tuberculosis (Mtb) based on the RPA targeting the B9 sequence was developed. The RPA-based detection of Mtb DNA was achieved within 20 minutes at 39°C. The analytical sensitivity of the test was one pg when tested using purified Mtb genomic DNA. The clinical performance of the RPA was evaluated using 387 sputum samples with the culture method as the gold standard. RPA and microscopy were compared to the gold standard in terms of sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value. The results showed that the sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value of RPA were 97.2% (95% CI: 93.5, 99.0), 92.2% (95% CI: 87.6, 95.2), 91.7% (95% CI: 87.8, 95.6), 97.4% (95% CI: 95.2, 99.7), 7.8% (4.2, 11.4), 2.8% (95% CI:0.4, 5.1), respectively, while microscopy had a sensitivity, specificity, positive predictive value, negative predictive value, false positive value and false negative value of 90.6% (95% CI: 85.4, 94.1), 88.8% (95% CI: 83.7, 92.5), 87.7% (95% CI: 83.0, 92.4), 91.5% (95% CI:87.6, 95.4), 11.2% (95% CI:6.9, 15.4) and 9.4% (95% CI:5.2, 13.6), respectively. RPA was found to be more sensitive and specific compared to microscopy, suggesting that the method has the potential to be used as a point-of-care (POC) TB diagnostic tool.
format Thesis
qualification_name Doctor of Philosophy (PhD.)
qualification_level Doctorate
author Salleh, Nur Eyuni Mohd
author_facet Salleh, Nur Eyuni Mohd
author_sort Salleh, Nur Eyuni Mohd
title Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
title_short Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
title_full Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
title_fullStr Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
title_full_unstemmed Development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
title_sort development of recombinase polymerase amplification assay for the detection of mycobacterium tuberculosis
granting_institution Universiti Sains Malaysia
granting_department Pusat Pengajian Sains Kesihatan
publishDate 2022
url http://eprints.usm.my/57346/1/NUR%20EYUNI%20BINTI%20MOHD%20SALLEH-FINAL%20THESIS%20P-SKD001416%28R%29%20-24%20pages.pdf
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