Comparison of encapsulated versus nonencapsulated (14) C-urea breath test for the detection of Helicobacter pylori infection: a scintigraphy study.
OBJECTIVE
(14) C-urea breath test ((14) C-UBT) is considered as "gold standard" for detection of active gastric H. pylori infection. However, till date no comparative study using encapsulated and non-encapsulated (14) C-UBT protocols has been conducted in same subjects in identical conditions. We monitored gastric fate of capsule containing (14) C-urea with real time display and compared sensitivities of these protocols at different time points of breath collection.


METHODS
Non-encapsulated (14) C-UBT was performed using 74 kBq of (14) C-urea in 100 dyspeptic patients by collecting breath samples at 10, 15 and 20 minutes. Thereafter, within 2 days a gelatin capsule containing (14) C-urea along with 6.0 MBq of (99m) Tc-diethylene triamine penta-acetic acid was administered to each patient for real time display of capsule movement and its fate in gastrointestinal tract by gamma camera. Simultaneously, breath samples were collected for (14) CO2 measurement during image acquisition.


RESULTS
Employing non-encapsulated (14) C-UBT, 74 out of 100 dyspeptic patients were found to be H. pylori positive. Discordant (14) C-UBT results were obtained in 4/74 (5.4%) cases using these two protocols. By employing encapsulated and nonencapsulated (14) C-UBT protocols, sensitivities of (14) C-UBT were found to be 90.5 versus 98.6% at 10 and 91.8 versus 97.2% at 15 minutes respectively; while these were 94.6 versus 100, 90.7 versus 98.6 and 83.7 versus 93.2% considering any one, two or all three positive values respectively.


CONCLUSIONS
Incomplete/non-resolution of (14) C-urea capsule in stomach during the phase of breath collections appears to decrease sensitivity of encapsulated (14) C-UBT as compared to nonencapsulated protocol for detection of H. pylori infection.
Department of Biophysics, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
Chander M
CM
Pathak
Balwinder
B
Kaur
Deepak K
DK
Bhasin
Bhagwant R
BR
Mittal
Sarika
S
Sharma
Krishan L
KL
Khanduja
Lalit
L
Aggarwal
Surinder S
SS
Rana
D000328:Adult; D000368:Aged; D001944:Breath Tests / Q000379:methods; D002250:Carbon Radioisotopes; D005260:Female; D005756:Gastritis / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000382:microbiology; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000382:microbiology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology; D011073:Polyamines; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D013270:Stomach / Q000382:microbiology* / Q000473:pathology; D013276:Stomach Ulcer / Q000382:microbiology; D014508:Urea / Q000032:analysis*; D055815:Young Adult
D002250:Carbon Radioisotopes; D011073:Polyamines; C005391:diethylenetriamine; D014508:Urea
Gastroduodenal diseases; Helicobacter pylori diagnosis; hp-eradication