Analysis of Metagenomic Next-Generation Sequencing Results of 25 Pus Samples

To explore the clinical value of detecting pathogens in pus samples by metagenomic next-generation sequencing (mNGS).

The 25 pus samples from infected patients were collected in this research. The positive rate and consistency of pathogenic bacteria detected by mNGS and conventional methods were compared. The pathogen types detected by the two methods were analyzed. Furthermore, the modifications of antibiotic treatment therapy were also evaluated based on mNGS results.

The sensitivity of mNGS method in detecting pathogenic bacteria in pus samples was better than that of conventional method (96% vs 40%; P < 0.01). Only 10 samples were detected pathogens by conventional methods, but 24 samples were detected by mNGS method. In specific, the results of conventional methods showed 10 samples had 11 kinds of pathogenic bacteria, of which 9 samples were single pathogen and 1 sample had two kinds of pathogenic bacteria. The results of mNGS method showed 24 samples were detected with 54 kinds of pathogenic bacteria, of which 15 samples were detected with single pathogen, and 9 samples were detected with two or more kinds of pathogenic bacteria. The two methods had 9(36%) consistent results, 14 (56%) completely different results, and 2 (8%) partially consistent results, and the kappa value was 0.19. Notably, mNGS could detect viruses, anaerobic bacteria, and other uncommon pathogens simultaneously.

The application of mNGS in the detection of pus specimens from different parts not only have high accuracy rate and also reduce the turnaround time of diagnosis. In addition, the performance of mNGS detection of anaerobic bacteria and caustic bacteria is better than conventional methods. The mNGS diagnosis in pus sample may play an important role in clinical diagnosis and treatment strategy decisions.