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

Abstract

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 μg 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.