Original ArticlesClinical Characteristics of Patients With Chronic Pancreatitis With or Without Prior Acute Pancreatitis Are DifferentTao, Heqing MD∗; Chang, Hong MD∗; Li, Nan MD†; Zhu, Shiwei MD‡; Duan, Liping MD∗ Author Information From the ∗Department of Gastroenterology †Research Center of Clinical Epidemiology ‡Department of Ultrasound, Peking University Third Hospital, Beijing, China. Received for publication June 10, 2021; accepted October 13, 2022. Address correspondence to: Liping Duan, MD, Department of Gastroenterology, Peking University Third Hospital, No. 49 N Garden Rd, Haidian District, Beijing, 100191, China (e-mail: [email protected]). The authors declare no conflict of interest. Pancreas 51(8):p 950-956, September 2022. | DOI: 10.1097/MPA.0000000000002142 Buy Metrics Abstract Objective The aim of the study is to clarify the clinical characteristics of patients with chronic pancreatitis (CP) who had no prior acute pancreatitis (AP) attack. Methods We retrospectively analyzed patients with CP who were admitted to our center between January 2012 and January 2020. Results A total of 274 patients were divided into the following 3 groups: group A: CP without prior AP (n = 103 [37.6%]), group B: CP preceded by a single episode of AP (n = 39 [14.23%]), and group C: CP preceded by recurrent AP (n = 132 [48.18%]). At the diagnosis, patients in group A had a higher incidence of pancreatic duct stones (41.7% vs 25.8%, P = 0.012), higher proportion of idiopathic CP (68.9% vs 48.5%, P = 0.001), and higher mean pancreatic volume change rate (37.61% vs 10.48%, P = 0.007) compared with Group C. Patients in group A underwent the most episodes of extracorporeal shockwave lithotripsy therapy among the 3 groups (P < 0.001). Conclusions Approximately 37.6% of patients had no prior AP attack before CP diagnosis. Patients with CP without prior AP had higher incidence of pancreatic duct stones and pancreas volume shrank faster. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.