Ileal dysfunction in Crohn's disease assessed by the postprandial serum bile acid response.

We assessed ileal functional integrity in 20 consecutive patients with Crohn's disease by sequential measurement of the postprandial serum bile acid concentration. In all 14 patients with active Crohn's disease involving the terminal ileum, the mean (+/- SEM) peak response in the cholylglycine (0.4 +/- 0.04 mumol/l, n = 14) as well as in the total serum bile acid concentration (2.0 +/- 0.4 mumol/l, n = 10) was similar to that seen in a group of children who had undergone ileal resection. A significantly greater increase in the cholylglycine (1.8 +/- 0.18 mumol/l, n = 16, P less than 0.01) and in the total serum bile acid concentration (9.8 +/- 2.4 mumol/l, n = 11, P less than 0.025) was noted in normal children. In five of the six remaining patients (three with Crohn's disease shown not to involve the ileum and two of three with asymptomatic, treated Crohn's ileitis) and in seven patients with ulcerative colitis, the meal stimulated responses were normal. These preliminary results suggest that measurement of the serum bile concentration after a meal stimulus may provide a valuable index of ileal inflammation in patients with Crohn's disease.