Effect of a test meal on the intragastric distribution of urea in the 13C-urea breath test for Helicobacter pylori.

Abstract

Test meals are invariably used in the B3C-urea breath test (UBT) but their effect on the intragastric distribution and gastric residence time of urea given in the test is unknown. The site of Helicobacter pyloni urease measured in the test is unknown and whether the test measures total or regional gastric urease is uncertain. This study reports the results of paired UBTs with simultaneous gastric distribution studies, one with and one without a fatty test meal, two weeks apart on seven H pyloni infected subjects. The test meal did not affect UBT results at 10 minutes, but increased values at 30 minutes and thereafter. The amount of scintigraphic label in the antrum at 10 minutes was also unaffected by the meal but increased at 30 minutes and thereafter, whereas the amount in the body/fundus was greatly increased both at 10 minutes and throughout the test. There was considerable variation in intragastric distribution of urea between subjects, both with and without the test meal. This study shows that a test meal profoundly affects intragastric distribution of urea solution in the UBT, and increases UBT values at 30 minutes and later. Variability between subjects, however, means that accurate measurement of total or regional gastric urease is probably unrealistic.

13C‐urea breath test without a test meal is highly accurate for the detection of Helicobacter pylori infection in Chinese

“…27,28 It has been shown that 13 C-UBTs at 10 min were unaffected by the use of test meal while values were signi®cantly greater at 30 min and later in their study. 26 However, the mean DOB was similar between 13 C-UBTs with or without a test meal at all time intervals in our study. It appears that the distribution, delivery and emptying of 13 C-urea may be different in Chinese populations.…”

“…An analogous situation was observed in the acid secretory pattern in an earlier study reported by us, in which acid output was signi®cantly greater in the Scottish population compared to Chinese, both in normal controls and duodenal ulcer patients. 29 It will be interesting to perform an isotope-labelled urea study in the Chinese population to study the distribution, delivery and emptying of 13 C-urea as described by Atherton et al 26 In conclusion, we have shown that for a low dose 75 mg 13 C-urea breath test protocol with or without a test meal, the optimal measurement interval was 30 min and the optimal DOB cut-off value was 5%. This low dose protocol without a test meal was highly accurate in the diagnosis of H. pylori infection in a Chinese population.…”

An optimized13C-urea breath test for the diagnosis ofH pyloriinfection

“…However, median DOB values at 20 and 30 min for both protocols showed significant differences (P = 0.006 and P = 0.001, respectively). These results are in accordance with those by Atherton et al [113] H Van der Hulst [46] 1999 LARA H, C 544 NA 100 Powder in 50 mL sterile water and Gisbert et al [47] , who showed that the test meal did not affect 13 C-UBT results at 10 min, but increased the values thereafter.…”

Diagnostic Accuracy of Urea Breath Test for Helicobacter Pylori Infection in Children With Dyspepsia in Comparison to Histopathology

“…Genetic variety of H. pylori strains and genetic specifications of the host can be important in this view. It has been shown by Atherton et al that the H. pylori load in a tissue sample is associated with specific genotypes called "cagA" and "vacA", in that cagA/vacA s1 strains infect more densely and severely than other strains (1) . The proportion of H. pyloriinfected subjects who are infected with different strains varies throughout the world.…”