Prognostic Associations of MEDS Section Score, Procalcitonin, and Lactate with 28-day Mortality in Adults with Sepsis: A Prospective Observational Study

Introduction: Early prognostic stratification in sepsis is difficult because individual biomarkers and clinical scores have limited accuracy. Aim: To assess procalcitonin, lactate, and the Mortality in Emergency Department Sepsis (MEDS) score for 28-day mortality and explore combined apparent discrimination. Materials and Methods: This hospital-based prospective observational study was conducted in the Department of General Medicine, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India from January to December 2025. Adults aged >18 years with sepsis according to Sepsis-3 criteria were eligible. Procalcitonin, lactate, and MEDS score within 24 hours of presentation were recorded. The primary outcome was all-cause 28-day mortality. Associations with mortality were assessed using logistic regression, and Receiver Operating Characteristic (ROC) curve analysis was performed to evaluate the prognostic discrimination of individual markers and their combinations. Results: Among 67 participants, the mean age was 56.76±13.78 years, with 38 (56.7%) females and 29 (43.3%) males. Fifty participants (74.6%) survived and 17 (25.4%) died. Non survivors had higher procalcitonin (11.13±8.46 vs 2.58±2.08 ng/ mL) and lactate (5.17±1.82 vs 1.88±0.64 mmol/L; both p-value <0.001). Mortality was 0/8 in very low-risk, 0/22 in low-risk, 5/25 in moderate-risk, and 6/6 in each high-risk and very highrisk MEDS category. All three markers were associated with mortality. Conclusion: MEDS score, procalcitonin and lactate were associated with 28-day mortality. Their combined apparent performance requires adequately powered external validation before clinical use.