Severe impairment of postprandial cholecystokinin release and gall-bladderemptying and high risk of gallstone formation in acromegalic patients during Sandostatin LAR

Background: Acromegalic patients treated three times daily with subcutaneou s injections of the somatostatin analogue octreotide frequently develop gal lstones, due to suppressed cholecystokinin release and impaired gall-bladde r emptying. Aim: To elucidate the effects of a new long-acting octreotide formulation ( Sandostatin LAR) on gall-bladder emptying, cholecystokinin release and gall stone formation. Methods: Postprandial gall-bladder and gastric emptying were determined by ultrasonography and cholecystokinin release was measured in seven patients on days 0, 14, 28, and 75 (Sandostatin LAR, 20 mg intramuscularly on days 1 , 30, and 60). Results: During treatment, fasting gall-bladder volumes increased from 26.5 +/- 3.2 mL to 61.4 +/- 7.5 mL, but postprandial cholecystokinin release an d gall-bladder emptying (from 63.9 +/- 3.8% to 12.3 +/- 3.5%) were severely suppressed. Gallstones formed in six out of seven patients within 8 months of treatment. Gastric emptying did not change during the therapy. Conclusions: The risk of gallstone formation is greatly increased during Sa ndostatin LAR. This is probably related to profound suppression of cholecys tokinin release and gall-bladder emptying.