[Performance and clinical usefulness of the 14CO2-glycocholate-breath-test]

14C-glycocholate breath-tests were performed in 22 clinical patients without gastointestinal disorders, in 11 cases with M. Crohn of the ileum and in 8 patients, in whom an intestinal overgrowth with bacteria was suspected. Additional to the usual discontinuous measurement of the specific activity of 14CO2 the exhaled amount of CO2 and 14CO2 and 14C-serum activity were determined. No advantage was found in the determination of the latter; for 1. discontinuous measurement of the specific activity of 14CO2 was sufficient for detecting disturbed enterohepatic bile-salt circulation; and 2. measurement of 14C-serum-activity or 14C-activity in cholic acids or protein were of no help in differentiating between bacterial overgrowth and diseases of the ileum. There remained doubts regarding the clinical usefulness of the test. Low specificity and many positive tests in patients without corresponding symptoms require that therapeutical procedures in such patients are initiated with some reserve.