Clinical value of Metagenomic Next- and Third-Generation Sequencing applied in ultrasound-guided puncture biopsy for diagnosing lymph node tuberculosis

Objectives

The aim of this study was to assess the clinical utility of metagenomic next-generation sequencing (mNGS) and metagenomic third-generation sequencing (mTGS) in diagnosing cervical lymph node tuberculosis through analysis of lymph node tissue.

Methods

This study recruited 101 patients with suspected cervical lymph node tuberculosis and took samples under ultrasound guidance. Parallel culture, X-pert, mNGS and mTGS workflows to each sample were performed. Taking clinical diagnosis as the gold standard, We comparatively compared diagnosis performance of the four methods.

Results

Clinically, 76 cases were diagnosed as lymph node tuberculosis and 20 cases were non-lymph node tuberculosis. Compared with clinical diagnosis, the sensitivities of mNGS and mTGS were 89.47 % and 82.89 %, respectively, significantly higher than those of culture and X-pert which were 43.28 % and 68.42 %, respectively (P < 0.05). The specificity of mNGS and X-pert reached 100 %, while those of culture and mTGS were 93.75 % and 95 %, respectively. And mNGS alone identified 7 species of bacteria, 3 species of viruses, and 5 species of fungi, and identified more mixed infections. Particularly, besides Mycobacterium tuberculosis detection, mNGS may be superior to mTGS for the detection of fungi. Pathogen identification of mNGS and mTGS is less affected by previous anti-tuberculosis drug usage.

Conclusion

mNGS and mTGS play a crucial role in the rapid diagnosis and accurate treatment on Cervical lymph node tuberculosis.