Comparison of the one-gram d-[14C]xylose breath test to the [14C]bile acid breath test in patients with small-intestine bacterial overgrowth.
In twelve patients with culture-proven bacterial overgrowth of the small intestine, the ability of a newly-developed one-gram d-[14C]xylose breath test to detect bacterial overgrowth was compared to that of the [14C]bile acid breath test. All patients manifested excessive production of breath 14CO2 after the administration of one gram [14C]xylose, with 83% of the patients being abnormal within the first hour of testing. In contrast, during the [14C]bile acid breath test, four of the twelve patients had no period of excessive 14CO2 production (above the 95% confidence range of controls). Nutrient malabsorption (fat, cobalamin, xylose) was seen with both true-positive and false-negative bile acid breath tests. The one gram [14C]xylose breath test, utilizing a substrate with more predominant absorption in the proximal small intestine and which can be catabolized by Gram-negative aerobic bacteria, appears to have a greater degree of sensitivity and specificity than the bile acid breath test in detecting the presence of small-intestine bacterial overgrowth.
D001424:Bacterial Infections / Q000175:diagnosis*; D001647:Bile Acids and Salts; D001765:Blind Loop Syndrome / Q000175:diagnosis; D001944:Breath Tests; D002245:Carbon Dioxide / Q000032:analysis; D002250:Carbon Radioisotopes; D006801:Humans; D007410:Intestinal Diseases / Q000175:diagnosis*; D007421:Intestine, Small / Q000382:microbiology; D014994:Xylose
D001647:Bile Acids and Salts; D002250:Carbon Radioisotopes; D002245:Carbon Dioxide; D014994:Xylose