Measuring gastric emptying of semisolids in children using the 13C-acetate breath test: a validation study.
OBJECTIVE
Radioscintigraphy is the gold standard for evaluation of gastric emptying in children, but requires exposure to ionising radiation. Therefore, the aim of the study was to validate the non-radioactive 13C-acetate breath test in children in comparison to radioscintigraphy as reference method.


METHODS
Twenty-nine children with dyspeptic or respiratory symptoms were tested for gastric emptying disorders simultaneously performing the 13C-acetate breath test and radioscintigraphy.


METHODS
A semisolid oatmeal was doubly labelled with 150 mg 13C-acetate and 50 MBq 99mTechnetium. Breath samples were collected every 5-10 min for 4 h. After mass spectrometrical 13C-analysis, curve fitting of the 13C-cumulative recovery to the modified power exponential function Y = m(1 - e(-kt) calculated the half emptying times of the breath test (t 1/2 (breath)). Scintigraphic image acquisition began immediately after the ingestion of the 99mTechnetium-labelled testmeal at a rate of one frame every 60 s for 1 h.


RESULTS
Six children showed delayed gastric emptying in scintigraphy (t 1/2(scinti) > 60 min). All these children had prolonged half emptying times t 1/2 (breath) in the 13C-acetate breath test. Using a cut-off t 1/2(breath) > 90 min, the 13C-acetate breath test had a sensitivity of 100% and a specificity of 85%. Scintigraphic and breath test half emptying times were linearly correlated (Y = 0.80x + 47.68, r = 0.76, P < 0.00001).


CONCLUSIONS
The 13C-acetate breath test proves to be a reliable, non-radioactive alternative for measuring gastric emptying in children.
Braden
B
B
Medical Department II, Johann Wolfgang Goethe University of Frankfurt/Main, Theodor Stern Kai 7, 60590 Frankfurt/Main, Germany. braden@em.uni-frankfurt.de
Peterknecht
A
A
Piepho
T
T
Schneider
A
A
Caspary
W F
WF
Hamscho
N
N
Ahrens
P
P
D000085:Acetates; D000293:Adolescent; D001944:Breath Tests / Q000295:instrumentation* / Q000379:methods; D002648:Child; D002675:Child, Preschool; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D006801:Humans; D008297:Male; D011877:Radionuclide Imaging / Q000379:methods; D012680:Sensitivity and Specificity
D000085:Acetates