Variation of enterohepatic circulation through the image with 75 SeHCAT in the first 3 hours. Scintigraphic patterns and análisis of its association with the diagnosis of bile acid malabsorption.

Objetive: To evaluate the enterohepatic circulation of 75-Selenium turoselecolic acid ( ⁷⁵ Se-SeHCAT) during the first 3 hours and its correlation with the abdominal retention at the 7 ^th day (AR ₇ ), as contribution to the clinical study of biliar acid malabsorption (BAM).
Materials and Methods: 38 patients with chronic diarrhea were retrospectively studied. Acquisition protocol included static abdominal images at 1 ^st , 2 ^nd and 3 ^rd hour and the 7 ^th day after oral administration of the radiopharmaceutical. Images of 1 to 3 hours determined 5 patterns of enterohepatic circulation that, due to their location, were characterized as: 1) gallbladder 2-3 hours, 2) gallbladder 3 hours, 3) gallbladder-abdomen 2-3 hours, 4) abdomen, 5) upper left abdomen. The association of these patterns with the AR ₇ (Fisher, STATA) were investigated. Patients were classified as Non BAM (AR ₇ >15%), mild-BAM (AR ₇ : 15-10%), moderate-BAM (AR ₇ : 10-5%) or severe-BAM (AR ₇ <5%).
Results: 19 patients had an AR ₇ diagnostic of BAM (7 mild-BAM, 5 moderate-BAM, 7 severe-BAM). The pattern "gallbladder at 2-3 hours" was statistically associated with Non BAM (p 0,008), while "gallbladder-abdomen at 2-3 hours" was correlated with having BAM (p 0,029).
Conclusion: Variations detected at the abdominal level in images during the first 3 hours were associated with changes in intestinal absorption and the incorporation of the radiopharmaceutical into the pool of bile acids, so visual interpretation of the images at 2 ^nd and 3 ^rd hour could be useful in the final assessment of the study.
(Copyright © 2021 Sociedad Española de Medicina Nuclear e Imagen Molecular. Publicado por Elsevier España, S.L.U. All rights reserved.)