[14C]urea breath test for diagnosis of Helicobacter pylori.
H. pylori is a potent urease producer, a characteristic that has been exploited in the development of the [14C]- and [13C]urea breath tests. The prevalence of H. pylori infection also is known to increase with advancing age; however, the individual patient's age has not routinely been considered when interpreting urea breath test results. The aim of this study was to validate a short, age-adjusted [14C]urea breath test for use in diagnosing H. pylori infections. Forty-one subjects (28 volunteers, 13 patients) underwent esophagogastroduodenoscopy with biopsies. Subjects were defined as being H. pylori-positive if histology or culture was positive. In addition, all subjects completed a 120-min [14C]urea breath test. A logistic regression analysis adjusting for age was used to estimate the probability of H. pylori positivity as a function of the 14C values generated. Sixteen subjects were H. pylori-positive, and 25 were H. pylori-negative. The 14C values generated between 15 and 80 min were found to be equally predictive in identifying H. pylori-positive subjects. Advancing age was associated with a higher probability of H. pylori-positivity. By taking advantage of the statistical probabilities, older patients could be accurately diagnosed with H. pylori at lower 14C values. We found that [14C]urea breath test to be both a sensitive and specific test that can be abbreviated to a 30-min examination (total test time). Moreover, our mathematical model indicates that a patient's age should be considered in order to optimize interpretation of the [14C]urea breath test, although further observations are needed to confirm this model.
Ormand
J E
JE
Department of Surgical Pathology, Mayo Clinic, Rochester, MN 55905.
Talley
N J
NJ
Carpenter
H A
HA
Shorter
R G
RG
Conley
C R
CR
Wilson
W R
WR
DiMagno
E P
EP
Zinsmeister
A R
AR
Phillips
S F
SF
D000367:Age Factors; D001944:Breath Tests; D002169:Campylobacter Infections / Q000175:diagnosis* / Q000453:epidemiology; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011237:Predictive Value of Tests; D012044:Regression Analysis; D014508:Urea
D002250:Carbon Radioisotopes; D014508:Urea