MARATTO

article · PLoS ONE

Diagnostic accuracy of the TrueNat™ MTB plus assay for detecting pulmonary tuberculosis in adults

In plain language

Tuberculosis remains a critical global health concern, with millions of cases missed due to the drawbacks of existing diagnostic tools such as slow cultures, insensitive microscopy, and tests requiring complex infrastructure. A cross-sectional evaluation of 260 adult participants with presumptive tuberculosis in northern Tanzania assessed the diagnostic performance of the TrueNat MTB Plus assay, a portable point-of-care tool. Sputum samples were evaluated against smear microscopy, culture, and Xpert MTB/RIF Ultra. TrueNat demonstrated strong diagnostic accuracy, with a sensitivity of 98.9 percent and specificity of 95.3 percent compared to culture, and 86.2 percent sensitivity with 95.2 percent specificity compared to Ultra. Overall, the portable assay compared favourably with conventional laboratory standards, providing fast results suitable for settings with limited medical and laboratory infrastructure.

Key takeaways

  • TrueNat showed 98.9 percent sensitivity and 95.3 percent specificity when evaluated against culture.
  • Compared to the rapid Ultra test, TrueNat demonstrated 86.2 percent sensitivity and 95.2 percent specificity.
  • Participants reporting weight loss were 2.84 times more likely to test positive for tuberculosis using TrueNat.

Why it matters

Millions of tuberculosis cases go undiagnosed each year because standard diagnostic methods are either too slow, inaccurate, or dependent on sophisticated laboratory infrastructure. Validating a portable, point-of-care test helps healthcare providers in resource-constrained environments detect infections rapidly and accurately, which is essential for timely treatment and curbing transmission.

Commercialisation angle

The findings support the clinical deployment of the TrueNat assay as a point-of-care diagnostic tool for clinics and healthcare providers operating in low-resource environments. Because the device is already endorsed by the World Health Organization and tested in a real-world clinical cohort, it represents an applied and near-market diagnostic solution, though further studies are required to assess broader operational implementation and direct impacts on patient management.

AI-generated from the published abstract. Always read the original work before citing.

Abstract

Tuberculosis (TB), caused by Mycobacterium tuberculosis remains a global threat, affecting 10.8 million people and causes 1.3 million deaths annually. Over 2.5 million cases go undiagnosed partly due to current diagnostic limitations. In particular, smear microscopy is less sensitive, culture is slow and prone to contamination, and the rapid Xpert® MTB/RIF Ultra (Ultra) needs advanced infrastructure. This study assessed the diagnostic accuracy of TrueNat™ MTB Plus assay (TrueNat), a portable, WHO-endorsed point-of-care tool, compared to Ultra, smear microscopy, and Löwenstein-Jensen (LJ) culture. This cross-sectional study enrolled 260 consenting adult participants (≥18 years) with presumptive TB in northern Tanzania. Participants' sputum samples were tested for M. tuberculosis using smear microscopy, LJ culture, Ultra and TrueNat. TrueNat performance was assessed using sensitivity, specificity, predictive values and area under the curve (AUC) against the standard-of-care and a composite reference standard. Age and body-mass-index were summarised using median and interquatile range (IQR). Categorical variables were reported as proportions. Multivariate logistic regression identified TB predictors (p < 0.05). Data analysis and visualization were conducted using R. Among 260 participants, 165 (63.5%) were male, with a median age of 46.0 years (IQR: 35.5-57.3); 15 (5.8%) were HIV-positive, and 52 (20%) had undernutrition. TB was detected in 109 (41.9%) participants by at least one test. TrueNat showed sensitivity/specificity of 34.4%/94.7% vs. smear microscopy, 98.9%/95.3% vs. culture, and 86.2%/95.2% vs. Ultra. The AUC values were 0.75, 0.92, 0.96, and 0.91 compared to smear microscopy, LJ culture, Ultra, and a composite reference method, respectively. Participants reporting weight loss were 2.84 times more likely (95% CI: 1.68-4.84, p < 0.001) to test positive for TB by TrueNat. The TrueNat compared favorably to both Ultra and culture in terms of diagnostic accuracy, offering the added benefits of faster results and greater suitability for resource-limited settings. These findings suggest that TrueNat is a promising test for rapid TB detection in low-resource settings, warranting further studies to evaluate its implementation and impact on patient management.

Research topics

  • Tuberculosis Research and Epidemiology
  • Image Processing Techniques and Applications
  • Bacterial Identification and Susceptibility Testing

Read the original research

This page summarises published work. The authoritative version sits with the publisher.

DOI: 10.1371/journal.pone.0327936

Is something wrong with this record? Report it or request removal.

Discussion

Discuss this research

Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.

No discussion yet. Open the first thread.