Microdose 14C-urea breath test offers diagnosis of Helicobacter pylori in 10 minutes.
OBJECTIVE
The urea breath test diagnoses Helicobacter pylori infection of the stomach by identifying the urease enzyme activity of the bacterium. In this "microdose" version of the test, 1 microCi 14C-urea is given orally in a capsule. Our objectives were: 1) to evaluate a microdose 14C-urea breath test capsule in a gastroenterology outpatient setting, 2) to determine the diagnostic ranges of the 14C-urea breath test for HP-positive and HP-negative patients, 3) to define the sensitivity and specificity of the test, and 4) to see whether breath sample results changed when they were mailed to a remote site for analysis.


METHODS
In a prospective blinded study, we breath-tested 200 fasted patients before elective outpatient endoscopy. At endoscopy, two gastric biopsy samples were taken and were examined for curved organisms; a third biopsy specimen was evaluated with a rapid urease test (CLOtest). Breath samples were mailed in aluminized balloons to a testing laboratory.


RESULTS
Using a single breath sample collected at 10 min, with > or = 200 dpm as positive, the breath test correctly classified 63 of 65 HP-positive patients (sensitivity 97%, CI 89-99%), and 128 of 135 HP-negative patients (specificity 95%, CI 90-98%). Radiation exposure from the test equated to natural background received in 1 day. No adverse events were caused by the breath test.


CONCLUSIONS
The 14C-urea capsule breath test (PYtest) is a convenient noninvasive test for the detection of gastric H. pylori infection. Accuracy is equivalent to invasive methods such as histology. Results can be obtained within 15 min if a counting instrument is nearby, or breath samples can be mailed to a testing laboratory for analysis.
Peura
D A
DA
University of Virginia Health Sciences Center, Martha Jefferson Hospital, Charlottesville, USA.
Pambianco
D J
DJ
Dye
K R
KR
Lind
C
C
Frierson
H F
HF
Hoffman
S R
SR
Combs
M J
MJ
Guilfoyle
E
E
Marshall
B J
BJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D001944:Breath Tests / Q000379:methods*; D004724:Endoscopy; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000201:enzymology / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors; D014508:Urea; D014510:Urease / Q000032:analysis
D014508:Urea; D014510:Urease