Post-ERCP pancreatitis in 2364 ERCP procedures: is intraductal ultrasonography another risk factor?

Background and study aims: Acute pancreatitis is considered a relevant major complication following endoscopic retrograde cholangiopancreatography (ERCP); according to literature data, the incidence varies between 1.5% and 17%. In the present study, we aimed to identify potentially new, hitherto unknown risk factors for post-ERCP pancreatitis. Patients and methods: A total of 2364 ERCP procedures performed in 1275 patients during the years 2004-2008 were included in the study. Post-ERCP pancreatitis was defined as acute abdominal pain within 48 hours following ERCP with at least 3-fold elevated levels of serum lipase and a requirement for analgesic drugs for at least 24 hours. The severity of the pancreatitis was determined using the Imrie score. Results: In our cohort study a total of 54 different patients (2.3%) developed post-ERCP pancreatitis. In 50 of these patients (92.6%) the pancreatitis was mild; in 54 (7.4%) it was severe. Patients with post-ERCP pancreatitis had highly significantly lower bilirubin levels than patients who did not have post-ERCP pancreatitis (P < 0.001). Length of hospital stay, duration of analgesics, and need for analgesic drugs were significantly higher in patients suffering from severe pancreatitis (P <= 0.01). In multivariate analysis, among other, already well-described risk factors we identified intraductal ultrasonography as another risk factor for post-ERCP pancreatitis, with a hazard ratio of 2.41 (P = 0.004). Conclusions: According to our retrospective data, intraductal ultrasonography seems to be another independent risk factor for developing post-ERCP pancreatitis, which needs to be further elucidated in prospective studies.