Helicobacter Forums

Hello,

I underwent a salvage treatment and took a breath test 2 months after the treatment. The test turned out negative. Although I am feeling a bit better, I still have lot of reflux (even worse than before) and sometimes also pain and bloating. I doubt the accuracy of the test I took as it looked pretty crappy to me, especially compared to the test displayed on Dr. Marshalls webpage. I basically exhaled into a two separate small test tubes and that was it. Dr. Marshall uses a balloon which to me looks much more effective. Can I trust the test and assume I am Hp. negative?

Thanks guys!

You are correct in that the test tube system for the C13 UBT is not foolproof. However, if the test tubes do not contain enough CO2, as sometimes happens, the machine will reject the sample and not give a result. The actual amount of breath collected is irrelevant because the machine measures a change in the ratio between normal C12-CO2 and C13-CO2 where the value at baseline (before taking isotope) is subtracted from the sample taken 20 minutes after drinking the C13 urea. If the ratio increases by more than a certain value (2.5 parts in 10,000 I recall), you have Hp.
In the PYtest C14 urea breath test, the balloon collection can hold enough for two breath tests so, even if the sample is poorly collected, there is usually spare breath in the balloon. Also, since the baseline amount of the tracer is always virtually zero, no baseline sample is required; just the 10 minute test sample. Once again, the ration of normal C12-CO2 to C14-CO2 is measured so, as long as there is some breath in the balloon, the test will still work.
Actually, breath tests are as accurate as a biopsy sample - but biopsy wins as a "gold standard" because several biopsy samples are usually taken and several tests can be done on them. But we don't want to have so many endoscopies.

Thank you for a thorough and informative reply!