Ammonia detection in Helicobacter pylori infections with the Ammonia Breath Analyzer (ABA) demonstrator. A pilot study to investigate the clinical application of the ABA.

Breath Tests, which are applied in the diagnosis of Helicobacter pylori
infection, all use the high urease activity of the micro-organism. The usual
breath tests measure the increase in CO2 excretion in expired air after
administration of 13C or 14C labeled urea. At the break-down of the urea,
however, also NH4+ and NH3 in the gaseous phase are released. Only one study
evaluated the measurement of this gas in exhaled air for the diagnosis of
Helicobacter pylori infections in a small group of 13 subjects. Five of them
were infected with Helicobacter pylori (according to a positive 14C-urea breath
test).

The aim of this study is to assess the change of ammonia exhaled in
Helicobacter pylori (HP) positive patients compared with patients that are not
HP infected after urea administration. In principle, in this pilot study, the
results of Kearney et al (Dig Dis Sci 2002, 47:2523-2530) are objectified. This
study showed that there was significant increase in ammonia exhalation from
HP-infected (N = 5) patients after urea administration. The non-infected
individuals (N = 9) showed no increase

The test variable is the concentration of the exhaled ammonia (ppm). Also the
respiratory ammonia output is determined (micro mol / min). Study design: In 30
HP+ and 30 HP non-infected infected patients these 2 variables are determined
for one hour following the administration of 300 mg of urea at t = 0 and the
administration of 500 mg Algeldraat at t = 30 minutes

The burden is very low. During the test the patients only have to breath into a
mouthpiece. Also the risk of administration of urea and Algedraat is considered
to be very low.