[75-Se-labeled bile acid analog absorption in various gastrointestinal diseases using a whole body counter].

Aim: It is possible to detect disturbances of bile acid absorption using a whole body counter after administration of Se-75 labelled bile acid analogues. We scrutinized the benefit of a modification of the test method.

Methods: We investigated 77 patients with different forms of a gastrointestinal disease. After application of Se 75 homotaurocholic acid we measured patient-activity up to 7 days later including whole-body profile scans in the first 6 h.

Results: The fractional retention after 7 days was between 20 and 67%. In cases of impaired absorption it was below 12%. Patients with liver diseases and after cholecystectomy (without bile acid resorption disturbance) showed normal values. Patients with Crohn's disease of the ileum or with intestinal ileac by-pass or with colestyramine treatment or with disturbance of vitamin B12-absorption or with cystic fibrosis showed a disturbance of bile acid absorption. The normal whole-body half-life was more than 2.8 days. The 24 and 72 h values were 62 and 31% in cases with normal absorption. Smaller values are signs of bile acid malabsorption. Impulse rates measured with the whole body counter are of an order of magnitude that allows to reduce the usually administered dose of 37 kBq to 9.25 kBq.

Conclusion: This is an efficient method to detect disturbances of bile acid absorption. The usually administered activity of 37 kBq can be reduced to 9.25 kBq.