Gallbladder contraction in patients with irritable bowel syndrome.

Impaired gallbladder contraction has been previously shown in pregnant women, in people with diabetes, celiac disease, and cystic duct syndrome, and in postvagotomy patients. In this study gallbladder contraction was measured by real-time ultrasonography in 32 subjects: 8 healthy controls, 12 diabetics and 12 with the irritable bowel syndrome. Contraction was expressed by four parameters: fasting gallbladder volume, residual gallbladder volume after maximal contraction, maximum percent of gallbladder emptied, and time elapsed until maximal contraction occurred. The main difference between the control subjects and the groups with diabetes and irritable bowel syndrome was found in the fasting and residual gallbladder volumes. Fasting volumes were twice as large in the irritable bowel syndrome (30.37 +/- 3.0 ml) as in the control subjects (15.15 +/- 0.69 ml, P less than 0.001). Residual volumes were also twice as great in those with irritable bowel syndrome, compared with the control subjects (12.91 +/- 2.18 ml vs. 5.6 +/- 0.58 ml, P less than 0.01). Similar, but less pronounced differences were found when the diabetic and the control subjects were compared. Fasting volumes were 21.7 +/- 2.62 ml for diabetic individuals vs. 15.15 +/- 0.69 ml for control subjects (P less than 0.05) and residual volumes were 10.87 +/- 2.69 vs. 5.6 +/- 0.58 ml (P = 0.1), respectively. The maximum percent emptied and the time elapsed until maximum contraction occurred were not statistically different. Also, no statistical difference was found between the diabetic individuals and those with irritable bowel syndrome in any of the parameters studied. Increased fasting and residual gallbladder volumes in the irritable bowel syndrome are changes that may promote sequestration and precipitation of cholesterol or calcium salts in the gallbladder of patients with lithogenic bile, as seen in diabetic individuals.