The impact of continuous subcutaneous infusion of octreotide on gallstone formation in acromegalic patients.

Treatment of acromegaly with intermittent sc injections of octreotide is associated with an increased incidence of cholelithiasis. We investigated the incidence of gallstone formation, the occurrence of gallbladder disease, and the response of gallstones to ursodeoxycholic acid in 30 acromegalic patients who were treated with a continuous sc infusion of octreotide at doses between 200 and 800 micrograms/day for 3-70 months. Of the 30 patients, 28 had pretretment ultrasonography of the biliary tree performed, and all had frequent follow-ups. Nine patients underwent pre- and posttreatment bile sampling. No patient treated for less than 6 months and 18.5% of patients treated for more than 6 months developed new gallstones. No patient developed symptomatic cholelithiasis while receiving octreotide therapy. Of six patients who developed gallstones, four were treated with ursodeoxycholic acid, which dissolved all gallstones. One patient with gallstones experienced an episode of biliary colic when octreotide was withdrawn; however, no cholecystitis was found at subsequent cholecystectomy. Bile sampling showed that 8 (75%) of the 12 patients who were assessed demonstrated microcrystals, whereas in 3 (50%) of 6 patients who were closely analyzed thereafter, microcrystals disappeared once octreotide therapy was stopped. Our results show that continuous sc infusion octreotide therapy increases the incidence of cholelithiasis over normal values, as is the case with intermittent sc injections. Although higher octreotide levels are sustained with continuous sc infusion, this is not associated with an increased risk of gallstone formation compared with intermittent sc octreotide therapy.