Incremental value of metagenomic next generation sequencing for the diagnosis of suspected focal infection in adults

Objectives Microbiological diagnosis is essential during clinical management of focal infections. Metagenomic next generation sequencing (mNGS) has been reported as a promising diagnostic tool in infectious diseases. However, little is known about the clinical utility of mNGS in focal infections. Methods We conducted a single-center retrospective study to investigate impact of mNGS on focal infection diagnosis and compared it with conventional methods, including culture, pathological examination, Xpert MTB/RIF, etc. 98 suspected focal infections cases were enrolled, and medical records were reviewed to determine their rates of detection, time-to-identification, and clinical outcomes. Results mNGS showed a satisfying diagnostic positive percent agreement of 86.30% (95% CI: 75.79–92.88%) in a variety of tissues, compared to 45.21% (95% CI: 33.68–57.24%) for culture and 57.53% (95% CI: 45.43–68.84%)f for conventional methods (p < 0.0125), and detected an extra 34 pathogenic microorganisms. Time requirement for pathogen identification using mNGS ranges from 31 h to 55 h, which showed an advantage over culture. (82.36 h; 95%CI: 65.83, 98.89; P < 0.05) Conclusions mNGS showed promising potential in pathogenic diagnosis during focal infections and might enable clinicians to make more timely and targeted therapeutic decisions.