Prognostic value of the C-reactive protein-to-albumin ratio in acute pancreatitis

Acute pancreatitis (AP) has a highly variable clinical course, making early identification of patients at risk of severe acute pancreatitis (SAP) essential for timely management. This study evaluated the ability of the C-reactive protein-to-albumin ratio (CRP/albumin ratio) at hospital admission to predict SAP and compared its performance with established prognostic scoring systems. This retrospective, single-center cohort study included 502 adults admitted with AP between January 2024 and December 2025. Disease severity was classified according to the revised Atlanta classification. The CRP/albumin ratio was calculated at admission and during serial follow-up, and its predictive performance was assessed using receiver operating characteristic (ROC) curve analysis and Firth logistic regression. Overall, 308 patients (61.4%) had mild, 130 (25.9%) had moderately severe, and 64 (12.7%) had severe AP. The admission CRP/albumin ratio was significantly higher in patients with SAP than in those with less severe disease (p<0.001), and the difference persisted during follow-up. The ratio demonstrated acceptable discrimination for SAP, with an area under the curve (AUC) of 0.796 (95% confidence interval [CI]: 0.666-0.925). A cut-off value of 24.89 provided 69.6% sensitivity and 86.0% specificity. Its discriminatory performance was comparable to that of the Acute Physiology and Chronic Health Evaluation II (APACHE II) score (AUC: 0.800; p=0.959). In complete-case multivariable Firth logistic regression involving 66 patients, including 23 with SAP, the CRP/albumin ratio remained independently associated with SAP (odds ratio: 1.035; 95% CI: 1.011-1.072; p<0.001). The admission CRP/albumin ratio may therefore serve as a simple and readily available complementary marker for early risk stratification in AP, although the proposed cut-off requires validation in prospective multicenter studies.