METTL7B Expression in Sepsis: Association With Disease Severity and 28-Day Mortality.

Abstract

Background: Sepsis is a life-threatening condition associated with high mortality, and current biomarkers remain suboptimal in prognostic evaluation. This study aimed to explore the associations of whole blood methyltransferase-like 7B (METTL7B) expression with disease severity and 28-day mortality in sepsis patients.

Methods: In this prospective cohort study (93 sepsis patients, 22 non-septic ICU controls), whole blood METTL7B (RT-qPCR) and conventional biomarkers (SOFA, PCT, CRP, IL-6) were measured. Dynamic SOFA changes (ΔSOFA from admission to Day 7) were assessed. ROC curves, logistic regression, and a combined model were used.

Results: METTL7B levels were significantly elevated in sepsis patients compared to non-septic controls (5.6 ± 1.33 vs. 2.44 ± 0.54, p < 0.001), with higher levels observed in non-survivors. Baseline METTL7B levels were significantly higher in patients with a deteriorating SOFA trajectory (ΔSOFA ≥ +2) compared to those with stable or improving courses (p < 0.05). The AUC for METTL7B alone in predicting 28-day mortality was 0.779, outperforming CRP and IL-6. The combination of METTL7B with SOFA and PCT achieved the highest predictive accuracy (AUC = 0.854). Multivariate logistic regression identified METTL7B as associated with disease severity and 28-day mortality risk in patients with sepsis (OR = 1.928, p = 0.017).

Conclusion: Elevated whole blood METTL7B expression is associated with disease severity and unfavorable outcomes in septic patients. When combined with dynamic SOFA and PCT, it improves prognostic stratification. These findings suggest its potential value as a severity-associated complementary marker warranting multi-center validation.