Preoperative Inflammatory Markers as Predictors of Post-ERCP Pancreatitis: A Retrospective Cohort Study

Post-ERCP pancreatitis (PEP) is the most common complication of ERCP. Identifying simple and accessible biomarkers to predict PEP risk may enhance patient safety and guide clinical decisions.

This retrospective, single-center study included 613 adult patients who underwent ERCP between January 2017 and December 2024. Demographic data, comorbidities, procedural details, and preoperative laboratory parameters were collected from institutional electronic health records. The primary outcome was the development of PEP, defined by standard diagnostic criteria.

Post-ERCP pancreatitis occurred in 52 patients (8.5%). Demographic characteristics and comorbidities, including age, sex, body mass index, diabetes mellitus, and hypertension, were not significantly associated with PEP. Pancreatic duct cannulation was significantly more frequent among patients with PEP (53.8% vs. 24.8%, p < 0.001) and remained an independent risk factor in multivariable analysis (aOR: 3.05, 95% CI: 1.65-5.64, p < 0.001). Patients who developed PEP had higher preoperative neutrophil-to-lymphocyte ratio (NLR) (3.7 ± 1.9 vs. 2.9 ± 1.5, p = 0.001) and C-reactive protein (CRP) levels (18.5 ± 11.2 vs. 11.4 ± 8.3 mg/L, p = 0.001). In adjusted analysis, both NLR (aOR: 1.14, 95% CI: 1.02-1.28, p = 0.02) and CRP (aOR: 1.04, 95% CI: 1.01-1.08, p = 0.008) remained statistically significant but modest independent predictors of PEP. ROC analysis demonstrated limited discriminative ability for both NLR (AUC: 0.64) and CRP (AUC: 0.66), with moderate sensitivity and specificity.

Elevated preoperative NLR and CRP levels, together with pancreatic duct cannulation, were independently associated with an increased risk of post-ERCP pancreatitis. Although these inflammatory markers demonstrated statistically significant associations, their predictive strength was modest. Therefore, NLR and CRP should be interpreted as supportive parameters rather than standalone predictors and may contribute to pre-procedural risk stratification when integrated with established clinical and procedural risk factors. Further prospective, multicenter studies are warranted to validate these findings and clarify their role in clinical practice.