Pancreatic steatosis is a strong risk factor for post-ERCP pancreatitis: An emerging concept.

Objective: The Endoscopic Retrograde Cholangiopancreatography (ERCP) is the treatment of choice for biliary obstruction but is associated with post-ERCP pancreatitis (PEP) in around 5 % of cases. No radiological criteria have been evaluated for predicting PEP risk.

Design: This retrospective study examined records of 1365 patients who underwent ERCP at our center between 2014-2023. Only sphincterotomy-naïve patients were included. CT scans within 30 days of ERCP were reviewed for radiological criteria. The optimal pancreatic density cut-off was determined using AUROC and Youden index. Logistic regression was used for analyses.

Results: PEP occurred in 75 patients (6.1 %). The CT scan was performed before ERCP for 565 of the total population. A fatty pancreas, defined as a spontaneous density less than -50HU, was statistically associated with PEP (OR: 7.35; 95 % CI: 1.56-26.5 p = 0.004), as well as with biliary obstruction due to stones (OR: 0.61; 95 % CI: 0.38-0.98; P = 0.04), the need for precut (OR: 2.19; 95 % CI: 1.35-3.51; P = 0.001), cannulation of the main pancreatic duct (OR: 2.23; 95 % CI: 1.36-3.59; P = 0.001), and the use of a pancreatic stent (OR: 2.48; 95 % CI: 1.29-4.47; P = 0.004). In multivariate analyses, only obstruction unrelated to gallstones (OR = 2.63; 95 % CI: 1.16-6.25; P = 0.024) and a low pancreatic density (<-50HU) (OR=7.94, 95 %CI: 1.59-31.09; P = 0.005) remains significantly associated with the risk of PEP, including after adjustment for age and sex (P = 0.006).

Conclusion: A very low pancreatic fat density could be a significant risk factor for post-ERCP pancreatitis with potential clinical and research implications. Further validation is needed.