131I-labeled bovine serum ablum: A valuable marker for solid in the measurement of gastric emptying

Abstract

AIM: Various methods for measurement of gastric emptying have received widely study. In clinic, ^99mTc-sulphur colloid (^99mTc-Sc), ¹³¹I fiber and ¹¹¹In-DAPA have been accepted as a valuable markers for digestive solid, non-digestive solid and liquid component respectively. However, half life period for ¹¹¹In is only 1.5 h which is so short that incur a problem for shipment, and non digestive marker of ¹³¹I fiber cannot response for the physiological function of the gut. In this study, we investigated the validity of ¹³¹I-bovine serum album (¹³¹I-BSA), a possible candidate for digestive solid marker, together with ^99mTc-DTPA as liquid marker in the determination of gastric emptying for solid and liquid simultaneously.

METHODS: In vitro, the solid phase of ¹³¹I-BSA labeled EGG were incubated in human gastric juice (pH 2.0), 1 N NaCl (pH 7.0) and 0.1 N HCl (pH 1.0) over a period of 2 h for analysis of its stability. Stability for the liquid phase of ^99mTc-DTPA and another solid phase of ^99mTc-Sc were also studied in the same manner. In vivo, gastric emptying were measured using ¹³¹I-BSA as solid marker and ^99mTc-DTPA as liquid marker in 35 patients with chronic gastric (group CG) and 10 healthy controls (group HC) to explore the ability of a combination of these 2 labels in the distinguishment of solid and liquid emptying.

RESULTS: Gastric emptying patterns of solid and liquid showed significant difference: solid emptying showed an evidence of lag phase and a significant prolongation of half emptying time for solid than that for liquid. Comparing to group HC, group CG showed a prolongation of solid lag time in 14 patients, slower half solid emptying in 15 patients and retarded liquid emptying rate in 12 patients. Solid emptying parameters for ¹³¹I-BSA were significant correlated to those for ^99mTc-Sc (r = 0.989, P < 0.01). Variability of solid emptying for ¹³¹I-BSA and ^99mTc-Sc, showed a maximal difference of 9.2% and a minimal difference of 0.8%.

CONCLUSION: ¹³¹I-BSA labeled EGG showed a higher stability in different solutions and had a pattern of emptying similar to that of ^99mTc-Sc, suggesting that ¹³¹I-BSA is a valuable digestive solid marker for detection of solid emptying. A combination of use of ¹³¹I-BSA, ^99mTc-Sc, and ¹¹¹In-EHIDA imultaneously in the measurement of gastric emptying and bile reflux is anticipated.

Key Words: ¹³¹I-labeled bovine serum album; Marker; Gastric emptying