AIM:To evaluate the risk factors of acute cholecystitisafter endoscopic common bile duct(CBD)stone removal.METHODS:A total 100 of patients who underwent en-doscopic CBD stone removal with gallbladder(GB)in situwithout subsequent cholecystectomy from January 2000to July 2004 were evaluated retrospectively.The follow-ing factors were considered while evaluating risk factorsfor the development of acute cholecystitis:age,gender,serum bilirubin level,GB wall thickening,cystic duct pa-tency,presence of a GB stone,CBD diameter,residualstone,lithotripsy,juxtapapillary diverticulum,presence ofliver cirrhosis or diabetes mellitus,a presenting illness ofcholangitis or pancreatitis,and procedure-related compli-cations.RESULTS:During a mean 18-mo follow-up,28(28%)patients developed biliary symptoms;17(17%)acutecholecystitis and 13(13%)CBD stone recurrence.Of patients with acute cholecystitis,15(88.2%)re-ceived laparoscopic cholecystectomy and 2(11.8%)open cholecystectomy.All recurrent CBD stones weresuccessfully removed endoscopically.The mean timeelapse to acute cholecystitis was 10.2 mo(1-37 mo)and that to recurrent CBD stone was 18.4 mo.Of the17 patients who received cholecystectomy,2(11.8%)developed recurrent CBD stones after cholecystectomy.By multivariate analysis,a serum total bilirubin level of<1.3 mg/dL and a CBD diameter of <11 mm at the timeof stone removal were found to predict the developmentof acute cholecystitis.CONCLUSION:After CBD stone removal,there is noneed for routine prophylactic cholecystectomy.However,patients without a dilated bile duct(<11 mm)and jaun-dice(<1.3 mg/dL)at the time of CBD stone removal AIM: To evaluate the risk factors of acute cholecystitis after endoscopic common bile duct (CBD) stone removal. METHODS: A total 100 of patients who underwent en-doscopic CBD stone removal with gallbladder (GB) in situwithout subsequent cholecystectomy from January 2000to July 2004 were as retrospectively. The follow-ing factors were considered while evaluating risk factors for the development of acute cholecystitis: age, gender, serum bilirubin level, GB wall thickening, cystic duct pa-tency, presence of a GB stone, CBD diameter, residualstone, lithotripsy , a preponderance of ovarian cirrhosis or diabetes mellitus, a presenting illness of cholangitis or pancreatitis, and procedure-related compli-cations .RESULTS: During a mean of 18-mo follow-up, 28 (28%) patients developed biliary symptoms; 17 17%) acutecholecystitis and 13 (13%) CBD stone recurrence. Oc patients with acute cholecystitis, 15 (88.2%) re-ceived laparoscopic cholecystectomy and 2 (11.8%) open cholecystectomy. resuccessfully removed endoscopically.The mean timeelapse to acute cholecystitis was 10.2 mo (1-37 mo) and that to recurrent CBD stone was 18.4 mo.Of the17 patients who received cholecystectomy, 2 (11.8%) developed recurrent CBD stones after cholecystectomy.By multivariate analysis, a serum total bilirubin level of <1.3 mg / dL and a CBD diameter of <11 mm at the time of stone removal were found to predict the development of acute cholecystitis. CONCLUSION: After CBD stone removal, there is noneed for routine prophylactic cholecystectomy. However, patients without a dilated bile duct (<11 mm) and jaun-dice (<1.3 mg / dL) at the time of CBD stone removal