THE TECHNIQUE

POC diagnosis is based on the UBT using C-14 capsules. This test system is easy to use for both patients and health care providers. No extra help is required from external facilities. The test results are available within 1-20 min after the patient has swallowed C-14 activated capsule. This capsule contains 1µCi C-labeled urea. The radioactive dose is very low, significantly less than the dose given during a normal X-ray.

THE DEVICE

The main analyser has two G.M.Tubes, both of which pick up the background radiation. Now, the breath analyser is inserted into only one of the two slots i.e. one of the two G.M.Tubes registers the radiation coming out from the breath analyser thus helping in canceling out any "Noise" radiation. The only output from the machine is : 0 if patient not infected, 2 if patient infected and 1 if borderline. The threshold values of radiation hits/counts that correspond to the above results can be managed by using an inbuilt programmable software. This can be used to change other parameters too, like, changing the amount of analysis time (which is generally 250 seconds). Furthermore, its a self-calibrating device performing checks and automatically calibrating itself when it is switched on.

STEPS TO DO THE TEST

The procedure is fast and simple with the following steps:
1) C-14 activated capsule is swallowed
2) After a 10-minute wait, the patient exhales into a breath analyser
3) Breath analyser is then inserted into the Analyser which is basically a small desktop GM-counter.
The results are obtained on-site, so there is no need to send samples to an external laboratory. The system is simple, rapid, practical, cost-effective and designed for the doctor’s office.

WORKING

A) On an empty stomach the patient swallows a C-14 activated capsule with a glass of water.
B) C-14 capsule, containing C-labeled urea, disintegrates rapidly in the stomach and the C-urea is dissolved.
C)In the presence of Helicobacter pylori, the C-urea is metabolized to carbon dioxide and ammonia by the enzyme urease, produced by Helicobacter pylori.
D)The available C isotopes, now in the form of CO2, diffuse into the blood to be transported to the lungs, where it is exhaled in the breath to be captured during sampling. A positive answer offers conclusive evidence that the patient is infected with Helicobacter pylori.
E)In the absence of Helicobacter pylori, the administered urea is absorbed in the gastrointestinal tract. and subsequently voided.

1.Convenience :Easy to use, near patient testing, no need to send samples for analysis.
2.Comfort :No invasive gastroscopic tubing.
3.Speed :Samples are ready for analysis in only 10 minutes and test result within minutes.
4.Reliability :Sensitivity 9% and specificity 100%.
5.Cost-effectiveness :No need for complex and expensive test equipment. Analysis made on-site.