To assess the long-term outcome in patients with acute cholecystitis treated initially by percutaneous cholecystostomy, the authors reviewed the medical and radiology records of all such patients treated at their hospital from January 1990 to September 1993. Of the 50 patients, 29 had calculous and 21 had acalculous cholecystitis. In the group with calculous cholecystitis, 1 of the patients required no further treatment, 3 subsequently underwent percutaneous stone removal, 14 underwent elective cholecystectomy, 6 underwent emergency cholecystectomy and 5 died of the underlying condition shortly after cholecystostomy. In the group with acalculous cholecystitis, 12 of the patients needed no further treatment after a mean follow-up period of 12 months; 8 of these underwent follow-up ultrasound examination, which revealed gallbladder calculi in only 1 patient. Four patients underwent elective cholecystectomy, 1 underwent emergency cholecystectomy, and 4 died of the underlying condition shortly after cholecystostomy. Over the long term, 23 (79%) of the 29 patients with calculous cholecystitis underwent surgery or removal of calculi. In the other group surgery was required in only 5 (24%) of the 21 patients. The authors conclude that percutaneous cholecystostomy is a useful temporizing measure, which allows patients with calculous cholecystitis to undergo elective cholecystectomy. In most cases of acalculous cholecystitis the procedure is curative, obviating the need for cholecystectomy.