The Value of Single-Molecule Nanopore DNA Sequencing in the Clinical Diagnosis of Suspected Tuberculosis Patients.

BACKGROUND

Early diagnosis of Mycobacterium tuberculosis (MTB) infection is of great significance for the clinical management of tuberculosis (TB). We first explored the efficacy of single-molecule nanopore DNA sequencing in the early diagnosis of suspected TB patients and analyzed the advantages in differentiating and diagnosing MTB and non-tuberculous Mycobacteria (NTM).

METHODS

In this cohort study, we reviewed the clinical data of suspected TB patients admitted from December 1, 2021, through April 15, 2022. All patients underwent 3 - 6 times acid-fast bacilli smear examinations of sputum, all of which were negative. To make a definitive diagnosis, we extracted specimens from the patients and performed specimen culture, Xpert MTB/Rif assay, and single-molecule nanopore DNA sequencing. The efficacy of different diagnostic methods in diagnosing suspected TB patients was compared using "Diagnostic Criteria for Pulmonary Tuberculosis" (WS288-2017) as the gold standard.

RESULTS

Among the 25 patients, 15 were infected with MTB, 5 were infected with NTM, 1 had mixed MTB and NTM infection, and 4 were negative. The accuracy of single-molecule nanopore DNA sequencing in diagnosing mycobacterial infection (MTB + NTM) was 92.0%, with a sensitivity of 90.5% and a specificity of 100%; the accuracy of diagnosing MTB infection was also 92.0%, with a sensitivity of 87.5% and a specificity of 100%. Single-molecule nanopore DNA sequencing showed an accuracy of 100% in differentiating MTB and NTM. However, the diagnostic accuracy and sensitivity of specimen culture and Xpert MTB/Rif assay were relatively low (≤ 52%) compared to "specimen culture + Xpert MTB/Rif assay". The diagnostic efficacy of single-molecule nanopore DNA sequencing was not affected by the source of tissue samples, while specimen culture and Xpert MTB/Rif assay could not diagnose mycobacterial infection using extrapulmonary specimens.

CONCLUSIONS

As a third-generation sequencing technology, single-molecule nanopore DNA sequencing has significant application value in diagnosing suspected TB patients. Compared to traditional diagnostic methods, such as specimen culture and Xpert MTB/Rif assay, single-molecule nanopore DNA sequencing exhibits high diagnostic efficacy, low error rate, and convenient detection.