Detection of by 16S Ribosomal RNA Gene PCR and Metagenomic Next-Generation Sequencing (mNGS)

In this study, the aim was to investigate the discriminatory power of molecular diagnostics based on mNGS and traditional 16S ribosomal RNA PCR among species. A total of fourteen clinical isolates from patients with positive cultures and clinical evidence were included between January 2017 and June 2020 in HeNan Provincial People's Hospital. DNA extraction and 16S rRNA PCR were performed on positive cultures, and pathogens were detected by mNGS in these same samples directly. Among the 14 isolates, four species were identified, and (8 cases) is the most common species. Twelve of the 14 spp. isolates were identified by the two methods, while two strains of were not identified by mNGS. All tested isolates showed susceptibility to trimethoprim-sulfamethoxazole (SXT), amikacin and linezolid. Apart from species, other pathogens such as , etc., were detected from the same clinical samples by mNGS. However, these different pathogens were considered as colonization or contamination. We found that it is essential to accurately identify species for determining antibiotic sensitivity and, consequently, choosing antibiotic treatment. 16S rRNA PCR was useful for identification of nocardial infection among species, while this technique needs the clinicians to make the pre-considerations of nocardiosis. However, mNGS may be a putative tool for rapid and accurate detection and identification of , beneficial for applications of antimicrobial drugs and timely adjustments of medication.