['The optimal treatment of acute cholecystitis is urgent laparoscopic cholecystectomy. Most reports suggest that a delay of 72 or 96 h from onset of symptoms leads to a higher conversion rate. This study assessed the conversion rate in relation to the timing of urgent laparoscopic cholecystectomy for acute cholecystitis.', 'During a 12 month period, 112 patients received laparoscopic cholecystectomy for acute cholecystitis at a tertiary care university hospital in central Taiwan. Data were collected prospectively.', 'The overall conversion rate was 3.6% (4/112). Of 62 procedures performed within 72 h from onset of symptoms, 2 were converted, as compared with 2 of 50 procedures after 72 h. Of 76 procedures performed within 96 h from onset of symptoms, 3 were converted, as compared with 1 of 36 procedures after 96 h. There were no mortalities or common bile duct injuries.'] Does urgent laparoscopic cholecystectomy in the management of acute cholecystitis : timing influence conversion rate?