Is the ¹³C-acetate breath test a valid procedure to analyse gastric emptying in children?

Background/Purpose: Scintigraphy is regarded as the 'gold standard' procedure in measuring gastric emptying (GE) rates. ¹³C-acetate breath test (ABT), which already has been validated in adults, is a noninvasive and nonradioactive alternative method. The aim of the current study was to validate ABT against technetium Tc 99m scintigraphy in children affected by delayed GE. Methods: Sixty children were recruited and divided into 2 groups: group A, 30 healthy controls; group B, 30 patients with gastroesophageal reflux, and scintigraphy-documented DGE (15 neurologically impaired). After an overnight fast, all of them underwent ABT using 25 to 150 mg ¹³C- acetate. Breath samples were obtained at baseline and then every 10 minutes for 2 hours. The ¹³CO₂ to ¹²CO₂ ratio in breath samples was analysed by isotope ratio mass spectrometry. Data are expressed as follows: time of peak ¹³C exhalation (tP¹³CO(2b)) and half emptying time in ABT (t(1/2b)), and scintigraphy half emptying time (t(1/2s)). Results: In controls tP¹³CO(2b) was 37 ± 13 minutes and t(1/2b) 74 ± 12 minutes. In patients tP¹³CO(2b) and t(1/2b) were, respectively, 65 ± 26 minutes and 104 ± 18 minutes t(1/2s) was 91 ± 21 minutes. In group B tP¹³CO(2b) and t(1/2b) were delayed significantly compared with controls, respectively, P <.03 and P <.01. In group B significant correlation between t(1/2s) and t(1/2b) was noted (r₁ = 0.97). A close correlation was also observed between t(1/2s) and tP¹³CO(2b) (r₂ = 0.95). Conclusion: The ¹³C ABT is an easy, reliable, and less expensive procedure for measuring GE, and its results closely correlate with those of scintigraphy in a paediatric population.