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Updated: Jul 22, 2026

Real Time Monitoring of Intracellular Bile Acid Dynamics Using a Genetically Encoded FRET-based Bile Acid Sensor
Published on: January 4, 2016
Measurement of bile acid half-life using [75Se]HCAT in health and intestinal diseases. Comparison with [75Se]HCAT
R Ferraris1, G Galatola, A Barlotta
1Department of Gastroenterology and Nuclear Medicine Service, Ospedale Mauriziano Umberto I, Turin, Italy.
Abstract:
The diagnostic values in detecting terminal ileum dysfunction using [75Se]HCAT have been assessed for two different scintigraphic techniques in 58 subjects. The measurement of [75Se]HCAT T1/2 in the enterohepatic circulation by daily gallbladder scintigraphy showed 78% sensitivity, 96% specificity, 96% positive predictive value, and 78% negative predictive value at the optimal cutoff level of 2.0 days; lower--but not significantly different--figures were observed for [75Se]HCAT total abdominal retention four and seven days after isotope administration, at the optimal cutoff levels of 40% and 22%, respectively. [75Se]HCAT T1/2 was then evaluated in 60 patients with various intestinal diseases. Sixty-nine percent (9/13) of patients with diarrhea of obscure origin showed abnormal [75Se]HCAT T1/2. Bile acid malabsorption using [75Se]HCAT can be investigated by the noninvasive measurement of its enterohepatic T1/2 and may play a pathogenetic role in patients with diarrhea of obscure origin.
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