REPEATABILITY OF THE SUGAR ABSORPTION TEST, USING LACTULOSE AND MANNITOL, FOR MEASURING INTESTINAL PERMEABILITY FOR SUGARS

Differential sugar-absorption tests for measuring intestinal permeabil ity for sugars have been studied in a variety of gastrointestinal dise ases. Their use in general practice has been hampered by a lack of dat a on reference values and repeatability of the test and the laboratory assay. In this study, we determined the reference values of the sugar -absorption test, using lactulose and mannitol as probe molecules, for children and adults. The repeatability of the test is good; linear re lationship: slope, 0.825 [95% confidence interval (CI), 0.571, 1.152); intercept, 0.005 (95% CI, -0.004, 0.010). The repeatability of the la boratory assay for the sugar-absorption test is excellent; linear rela tionship: slope, 1.014 (95% CI, 0.870, 1.094); intercept, 0.002 (95% C I, -0.005, 0.010). The validation of the sugar-absorption test makes t he test useful as a simple, noninvasive, reliable intestinal permeabil ity test for sugars, which can be of use for clinical practice. Taking possible interfering factors into account, the sugar-absorption test can be used as a diagnostic test for enteropathy of different etiologi es and evaluation of therapeutic interventions in both children and ad ults. Studies with the sugar-absorption test may clarify the role of i ntestinal permeability in the pathophysiology of a variety of gastroin testinal diseases.