Metagenomic Next-Generation Sequencing Improves The Prognosis of Patients With Infectious Diseases on Mechanical Ventilation in The Intensive Care Unit (ICU)

Background: Metagenomic Next-Generation Sequencing (mNGS) has gradually shown its advantages in pathogen identification for clinical infectious disease. However, few studies were conducted on the evaluation between this technique and conventional methods like culture and PCR and the prognosis of patients with infectious diseases on mechanical ventilation in ICUMethods: We conducted this retrospective study from March 2018 to May 2020 in the first Affiliated Hospital of Guangzhou Medical University, a total of 228 patients with suspected infectious diseases on mechanical ventilation were included, including 104 cases of mNGS group and 124 cases of non-mNGS. Statistical analyses were performed between the two groups and subgroup of whether were immunocompromised. The concordance between mNGS, culture and PCR was also assessed.Results: The 28-day mortality rate of the patients in the mNGS group was lower after the baseline difference correction (19.23% vs. 29.03%，p=0.039), indicating that mNGS may improve the prognosis of patients in ICU. And subgroup analysis showed that mNGS could improve the 28-day mortality of nonimmunosuppressive patients（14.06% vs. 29.82%, p=0.018）. According to the analysis of Logistic Regression, not performing mNGS, high APACHE II score and hypertension were independent risk factors for 28-day mortality, which strongly suggested that mNGS was one of the key factors affecting prognosis. A total of 157 samples performed mNGS, 116 of them received both mNGS and culture. mNGS presented advantages of positivity (69.8% double positive and 25.0% mNGS positive only) and concordance (79.0%, match and partly match).Conclusions: mNGS may improve the prognosis and reduce the 28-day mortality rate of patients with infectious diseases on mechanical ventilation in ICU. This technique has shown its advantages comparing with conventional methods, and will be wildly used as a promising technology for infectious disease.