Roles of gall bladder emptying and intestinal transit in the pathogenesis of octreotide induced gall bladder stones

Background-Octreotide treatment of acromegalic patients increases the % deoxycholic acid conjugates and the cholesterol saturation of gall bladder bile, and induces gall stone formation. Aims-To study the roles of gall bladder emptying and intestinal transit in these phenomena. Methods and patients-Gall bladder emptying and mouth to caecum transit was measured in (a) control subjects and acromegalic patients given saline or 50 mu g of octreotide, and (b) acromegalic patients taking long term octreotide. In the second group, large bowel transit was also measured. Results-A single dose of octreotide inhibited meal stimulated gall bladder emptying, the ejection fraction falling from mean (SEM) 66.0 (2.3)% to 7.0 (5.3)% in controls (p<0.001); from 72.5 (2.1) to 16.6 (5.1)% in untreated acromegalic patients (p<0.001), and to 30.4 (9.5)% in acromegalic patients taking long term octreotide (p<0.001 v untreated acromegalic group). Octreotide prolonged mouth to caecum transit time, from 112 (15) min to 237 (13) min in controls (p<0.001), from 170 (13) min to 282 (11) min in untreated acromegalic patients (p<0.001), and to 247 (10) min in acromegalic patients taking long term octreotide (p<0.001 v untreated acromegalic patients). The mean large bowel transit in octreotide untreated compared with treated acromegalic patients remained unchanged (40 (6) h v 47 (6) h). Conclusions-Prolongation of intestinal transit and impaired gall bladder emptying may contribute to lithogenic changes in bile composition and gall stone formation in patients receiving long term octreotide.