Efficacy of lactulose plus 13C-acetate breath test in the diagnosis of gastrointestinal motility disorders.
BACKGROUND
We designed a new method of measuring gastric emptying and orocecal transit time (OCTT) at the same time to assess the influence of gastric emptying upon OCTT.


METHODS
Twenty-five dyspeptic patients (6 men, 19 women) with a mean age of 64.8 years (range, 25-80 years) were studied. The patients received a liquid test meal, containing 100 mg of 13C-acetate and 12g of lactulose, while they were in the sitting position after an overnight fast. Breath samples were collected at 10-min intervals of 120 min and both 13CO2 and hydrogen (H2) levels were measured. Subsequently, H2 concentrations were measured at 30-min intervals, for a total of 240 min.


RESULTS
The results of gastric emptying were expressed as the time of peak 13CO2 excretion. OCTT was defined as the period between the ingestion of lactulose and a H2 peak rise of 5 ppm above the baseline value. The onset of H2 enrichment in the breath began at 90-110 min, whereas 13CO2 levels increased from the beginning, with peak enrichment values being reached after 60-80 min. OCTT was related to 13CO2 peak time. In 5 of the 25 patients, H2 breath enrichment in the 10-min sample was more than 5 ppm over the baseline value. All these 5 patients had double or triple peaks in serial breath H2 concentrations.


CONCLUSIONS
The combination of the lactulose hydrogen breath test (LHBT) with the 13C-acetate breath test, which requires only breath samples, provides us with much information on the gastrointestinal tract; gastric emptying, OCTT, bacterial overgrowth in the small intestine, colonic fermentation, and oropharyngeal flora. The 13C-acetate breath test can be useful as an adjuvant test when LHBT is performed for measuring OCTT.
First Department of Internal Medicine, Toho University, School of Medicine, Tokyo, Japan.
Yoshihisa
Y
Urita
Kazuo
K
Hike
Naotaka
N
Torii
Yoshinori
Y
Kikuchi
Masahiko
M
Sasajima
Kazumasa
K
Miki
D000085:Acetates; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001944:Breath Tests / Q000379:methods*; D002245:Carbon Dioxide / Q000032:analysis; D004415:Dyspepsia / Q000175:diagnosis*; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005772:Gastrointestinal Transit / Q000502:physiology*; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007792:Lactulose; D008297:Male; D008875:Middle Aged
D000085:Acetates; D002245:Carbon Dioxide; D007792:Lactulose; D006859:Hydrogen