Diagnostic yield of Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB assays on non-pulmonary samples from suspected cases of extra-pulmonary tuberculosis (EPTB).
Anvita Gupta Malhotra, Leena Lokhande, Abhijit Pakhare, Payal Soni, Satya Prakash Vishwakarma, Anand Kumar Maurya, Jitendra Singh, Sarman Singh
{"title":"Diagnostic yield of Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB assays on non-pulmonary samples from suspected cases of extra-pulmonary tuberculosis (EPTB).","authors":"Anvita Gupta Malhotra, Leena Lokhande, Abhijit Pakhare, Payal Soni, Satya Prakash Vishwakarma, Anand Kumar Maurya, Jitendra Singh, Sarman Singh","doi":"10.1007/s10096-025-05177-7","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Extrapulmonary tuberculosis (EPTB) poses a diagnostic challenge due to its paucibacillary nature and low diagnostic yield of traditional methods. Molecular diagnostic tools like Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB offer promising alternatives for the rapid and higher detection rates for pulmonary TB samples. However, the yield of these newly introduced molecular tests on extra-pulmonary samples requires country-specific evaluation and comparative analysis.</p><p><strong>Methodology: </strong>This study evaluated the diagnostic performance of Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB assays in detecting EPTB on 211 clinical specimens collected at a tertiary care centre of central India. The assays' sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPP) were compared against a composite reference standard.</p><p><strong>Results: </strong>Xpert MTB/RIF Ultra exhibited the highest sensitivity (50%) for EPTB detection, outperforming the standard GeneXpert MTB/RIF (29.4%) and Truenat MTB (35.3%), with comparable specificity across all three assays. Among the specimen types, pus samples demonstrated the highest (value) diagnostic yield. These findings highlight the superior diagnostic capabilities of Xpert MTB/RIF Ultra, particularly in paucibacillary cases.</p><p><strong>Conclusion: </strong>Xpert Ultra demonstrates superior sensitivity for EPTB detection compared to Xpert MTB/RIF and Truenat MTB, making it a promising tool to enhance diagnostic accuracy in paucibacillary TB. Its adoption as a standard diagnostic method could significantly improve EPTB management. These findings advocate for integrating advanced molecular diagnostics into routine tuberculosis workflows to reduce diagnostic delays and improve patient outcomes.</p><p><strong>Clinical trail number: </strong>Not applicable.</p>","PeriodicalId":11782,"journal":{"name":"European Journal of Clinical Microbiology & Infectious Diseases","volume":" ","pages":""},"PeriodicalIF":3.7000,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Clinical Microbiology & Infectious Diseases","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s10096-025-05177-7","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Extrapulmonary tuberculosis (EPTB) poses a diagnostic challenge due to its paucibacillary nature and low diagnostic yield of traditional methods. Molecular diagnostic tools like Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB offer promising alternatives for the rapid and higher detection rates for pulmonary TB samples. However, the yield of these newly introduced molecular tests on extra-pulmonary samples requires country-specific evaluation and comparative analysis.
Methodology: This study evaluated the diagnostic performance of Xpert MTB/RIF, Xpert MTB/RIF Ultra, and Truenat MTB assays in detecting EPTB on 211 clinical specimens collected at a tertiary care centre of central India. The assays' sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPP) were compared against a composite reference standard.
Results: Xpert MTB/RIF Ultra exhibited the highest sensitivity (50%) for EPTB detection, outperforming the standard GeneXpert MTB/RIF (29.4%) and Truenat MTB (35.3%), with comparable specificity across all three assays. Among the specimen types, pus samples demonstrated the highest (value) diagnostic yield. These findings highlight the superior diagnostic capabilities of Xpert MTB/RIF Ultra, particularly in paucibacillary cases.
Conclusion: Xpert Ultra demonstrates superior sensitivity for EPTB detection compared to Xpert MTB/RIF and Truenat MTB, making it a promising tool to enhance diagnostic accuracy in paucibacillary TB. Its adoption as a standard diagnostic method could significantly improve EPTB management. These findings advocate for integrating advanced molecular diagnostics into routine tuberculosis workflows to reduce diagnostic delays and improve patient outcomes.
期刊介绍:
EJCMID is an interdisciplinary journal devoted to the publication of communications on infectious diseases of bacterial, viral and parasitic origin.