Red Cell Distribution Width at 24 Hours as an Early Predictor of Mortality and Severity in Acute Pancreatitis: A Multicenter Retrospective Cohort Study

Background and Objectives: Acute pancreatitis (AP) presents with variable severity, and early identification of patients at risk for poor outcomes remains challenging. Red cell distribution width (RDW) is a widely available marker with potential prognostic value. Materials and Methods: We analyzed 682 patients from the RO-API/BUC-API registry admitted with AP between 2015 and 2023. RDW measured at 24 ± 6 hours post-admission was assessed for associations with severity (per Revised Atlanta Classification) and in-hospital mortality. ROC analysis and logistic regression were applied. Results: Median RDW was significantly higher in non-survivors and patients with severe disease. RDW ≥13.85% predicted mortality (AUC = 0.67), and ≥14.35% predicted severe AP (AUC = 0.67). RDW remained an independent predictor after adjusting for age. Conclusions: RDW at 24 hours is a useful early biomarker for predicting severity and mortality in AP.