Etiology and Severity Profiles of Acute Pancreatitis in Consecutive Admissions at a Japanese Acute-care Hospital: Comparison with the 2016 Nationwide Survey.

Objective　Nationwide surveys have characterized acute pancreatitis (AP) in Japan; however, their applicability to consecutive acute-care admissions remains uncertain. We compared the etiological and severity profiles of consecutive AP admissions at a Japanese acute-care hospital with those in a 2016 nationwide epidemiological survey.Methods　This retrospective single-center cohort included each patient's first AP hospitalization at our institution from April 2014 to March 2025. AP was diagnosed using the Japanese clinical criteria and classified according to the Japanese severity criteria (2008). The etiology was categorized as gallstone-related, alcohol-related, idiopathic, or other. Distributions were compared using chi-square tests and Cramér's V.Patients　In total, 357 patients were included.Results　The etiologies were gallstone-related in 126 patients (35.3%), alcohol-related in 63 (17.6%), idiopathic in 69 (19.3%), and other in 99 (27.7%). The distribution differed from that in the nationwide survey (P ＜0.001; Cramér's V = 0.11), with more gallstone-related cases and fewer alcohol-related cases. Age was associated with etiology (P ＜0.001; Cramér's V = 0.25). Severe AP occurred in 34.0% of patients versus 23.6% nationwide (P ＜0.001; Cramér's V = 0.07). In-hospital mortality did not differ significantly (2.8% vs. 1.8%, P = 0.19) between the two groups. Urgent endoscopic retrograde cholangiopancreatography was performed in 55.6% of the gallstone-related cases.Conclusion　Consecutive acute-care admissions differed from the 2016 nationwide survey in terms of etiological and severity profiles, whereas in-hospital mortality did not differ significantly.