Why should one do the Heli-test?

There are can be several motives:

- stomach pain ;

- doctor suspects gastritis or ulcer (of stomach or duodenum);

- monitoring of eradication therapy..

Up to the last time the hydrochloric acid hypersecretion was considered a primary cause of gastritis and ulcers, so the healing was mainly based on acidity reducing medicine. In 1980-th it was discovered that the most cases of ulcers and gastritis are conditioned by Helicobacter pylori.

If therapy does not include preparations which give rise to bacterium destruction the disease is recured as a rule. If Н. рylori is fully eradicated the duodenum and stomach ulcer annual recurrence diminishes from 65-80% to 2-6%.

The most frequenly used methods of Н. рylori detection are listed in the table below. Among them are hystology, cytology, serology, rapid urease test, polimerase chain reaction, phase-contrast microscopy and bacterioculture test.

	Direct	Indirect
Invasive	Bacterioculture test	Rapid urease test
	Polimerase chain reaction	Hystology
		Cytology
		Phase-contrast microscopy
Non-invasive		Isotope breath test
		Serology

As a rule the H. pylori presence is detected by histological examination of the stomach tissues. This method is rather accurate but if bacterium distribution is irregular (it can be present at the stomach body and absent at its antral part or vice versa) then one can obtain false-negative results. Moreover all biopsy methods are invasive that

a. creates certain discomfort for patients and

b. enhances the risk of instrumental infection.

A relatively precise noninvasive method is a serologic test which detects antibodies to Helicobacter pylori. Antibodies to H. pylori are detected at 95% of the infected patients. However, this test is not suitable for monitoring of conducted therapy since antibodies can remain in serum for several (from 4 up to 24) months when there are no bacteria in the stomach.

Non-invasive isotope breath test is much more adequate for therapy monitoring, moreover it can successfully be used in diagnostic purposes because its high sensitivity (98%) and specificity (100%) allows to detect H. pylori at the early stages of disease.