Sensitivity and reproducibility of a bile reflux test using 99mTc HIDA

We have studied the sensitivity and reproducibility of entero-gastric bile reflux measurements using a gamma camera. Aspiration of the stomach at the end of the study in a group of 14 patients showed that less than 1% of the administered HIDA was present in 7 patients who were judged reflux negative. In all 7 patients considered reflux positive, there was more than 1% of the dose in the stomach (median 8.2%, p less than 0.01 Mann-Whitney). The second group of 20 patients was studied twice in the same week with a 48 h interval between the tests. The results were reproduced in 15 patients (75%). Finally, the gamma camera technique was compared with nasogastric aspiration on a separate occasion. There was agreement in 16 patients out of 19(84%). These results suggest that the test is sensitive, and the lack of reproducibility is compatible with day to day variation in entero-gastric reflux.