Breath sample collection through the nostril reduces false-positive results of 13C-urea breath test for the diagnosis of helicobacter pylori infection.
BACKGROUND
One of the disadvantages of '3C-urea breath test is possible interference by urease activity not related to Helicobacterpylori.


OBJECTIVE
We design the simple and non-invasive modification to avoid the contamination of 13CO(2) produced in the mouth.


METHODS
One hundred and twenty-nine patients who underwent diagnostic upper endoscopy were enrolled. Within 1 week of the endoscopic procedure, each patient received the modified 13C-urea breath test. Breath samples were collected at baseline and at 1, 3, 5, 10, 15, 20 and 30 min after ingestion of 100 mg 13C-urea solution through the mouth and the nostril at each time point.


RESULTS
The breath delta13CO2 value through the nostril at 1 min was already higher in H. pylori-positive patients than in H. pylori-negative patients. Using 2.5% as the cut-off value, the sensitivity and specificity of the modified 13C-urea breath test at 20 min were both 100%, whereas the sensitivity and specificity of the standard 13C-urea breath test were 97.7 and 94%, respectively, using 3% as the cut-off value.


CONCLUSIONS
The modified 13C-urea breath test in which breath samples are collected through the nostril provides an easy way of avoiding false-positive results for the detection of H. pylori infection.
Urita
Y
Y
Division of Gastroenterology and Hepatology, Toho University School of Medicine, Tokyo, Japan. foo@eb.mbn.or.jp
Hike
K
K
Torii
N
N
Kikuchi
Y
Y
Kanda
E
E
Kurakata
H
H
Sasajima
M
M
Miki
K
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D001944:Breath Tests / Q000379:methods*; D002247:Carbon Isotopes; D016099:Endoscopy, Gastrointestinal; D005189:False Positive Reactions; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014508:Urea / Q000302:isolation & purification*
D002247:Carbon Isotopes; D014508:Urea