BILE-ACID ABSORPTION FROM ILEOANAL POUCHES USING ENEMA SCINTIGRAPHY

It is unclear whether bile acid absorption is affected by ileoanal pou ch construction. Bile acid absorption was measured in the abdomen of 1 6 patients with pouches (nine with good and seven with poor pouch func tion based on a clinical score) and in six patients with an end ileost omy using a radiolabelled synthetic bile acid ((75)SeHCAT) enema and d ynamic scintigraphy. The median (interquartile range) (75)SeHCAT absor ption was 81 (79-87) per cent in patients with ileostomy, 46 (43-53) p er cent in patients having well functioning pouches, and 24 (18-38) pe r cent in the group with poor pouch function (P<0.01). Log transformat ion of the absorption curves revealed a two-component uptake (fast com ponent t(1/2) = 1.4-7.2 min; slow component t(1/2) = 16-144 min) in al l patients with ileostomy, in eight of nine patients with pouches with good function, and in one of seven patients with a poorly functioning pouch (P<0.05); in the other six patients with poorly functioning pou ches, only the slow component of absorption was present. This test sho wed significantly reduced bile acid absorption in patients with an ile oanal pouch and gave an objective discrimination between well and poor ly functioning pouches.