Study on the early diagnostic value of nanopore sequencing in alveolar lavage fluid smear-negative pulmonary tuberculosis.

The objective of this study was to investigate the early diagnostic value of nanopore sequencing in alveolar lavage smear-negative pulmonary tuberculosis (PTB). A prospective study was conducted on patients hospitalized at Zhuzhou Central Hospital from October 2021 to June 2022 and suspected to have PTB. Alveolar lavage fluid specimens were collected from these patients and simultaneously subjected to centrifugal bacterial collection smear method in a sandwich cup, bifidobacteria solid culture (referred to as culture), Mycobacterium tuberculosis-DNA (TB-DNA), and nanopore sequencing for detection of Mycobacterium tuberculosis. These patients were ultimately diagnosed with smear-negative PTB. The final clinical diagnosis was used as a reference to compare the diagnostic efficacy of Nanopore sequencing, culture, and TB-DNA for PTB. The results showed that the positive rates detected by nanopore sequencing, culture, and TB-DNA in the 103 suspected tuberculosis patients were 73.8%, 13.6%, and 33.0%, respectively. The sensitivity of nanopore sequencing was significantly higher than culture (P < 0.001) and TB-DNA (P < 0.001) for the identification of smear-negative PTB. Similarly, the positive rate of TB-DNA was also significantly higher than that of culture (P = 0.001). In conclusion, nanopore sequencing exhibited the highest sensitivity for the rapid diagnosis of Mycobacterium tuberculosis in alveolar lavage fluid specimens, using clinical diagnosis as a reference standard, and it could improve the PTB clinical diagnosis.