mNGS and Sepsis Mortality Reduction

Objectives: To evaluate the utility of metagenomic next-generation sequencing (mNGS) in guiding antibiotic regimen adjustments for septic patients admitted to the intensive care unit (ICU), and to assess its impact on 28-day mortality. Methods: A retrospective study was conducted on 303 patients with sepsis admitted to the ICU between January 2021 and December 2022. Patients were divided into the mNGS group (93 cases) and the non-mNGS group (130 cases). Statistical analysis included linear regression, binary logistic regression, propensity score matching (PSM), and mediation analysis. Results: A 1:1 PSM was performed for the two groups, yielding a matched cohort of 80 patients per group. In the matched cohort, antibiotics adjustments based on pathogenic detection results were more frequent in the mNGS group than in the non-mNGS group (P < 0.01). No significant differences were observed between the two groups in ICU length of stay or total hospitalization costs (P > 0.05). Binary logistic regression further confirmed significant associations of mNGS detection with a higher likelihood of antibiotic adjustment (odds ratio [OR] = 39.082, P <0.01) and earlier time to antibiotic adjustment (OR = 0.663, P < 0.01). Each 1-point increase in the Sequential Organ Failure Assessment (SOFA) score was associated with a 17.4% higher risk of mortality (OR = 1.174, 95% CI [1.074, 1.283], P = 0.001). The decision of antibiotic adjustment (OR = 4.205, P = 0.001), urinary tract infection (OR = 3.682, P = 0.024) and the negative etiological culture (OR = 3.268, P = 0.047) were significantly positively associated with 28-day mortality. The treatments of mechanical ventilation (OR = 0.275, P = 0.004) and continuous renal replacement therapy (CRRT) (OR = 0.191, P = 0.001) were negatively related to 28-day mortality. However, the indirect effect of mNGS detection on 28-day mortality through antibiotics adjustment was not significant (Z = 0.367, P = 0.714). Conclusion: The mNGS detection facilitates antibiotic regimen adjustment and is associated with reduced 28-day mortality in septic ICU patients, without incurring higher healthcare costs or prolonging ICU length of stay. These findings highlight its potential for broader clinical application.