DIAGNOSIS OF HELICOBACTER-PYLORI

Helicobacter pylori is a gram-negative bacterium which colonizes the gastric mucosa. It causes chronic active gastritis and is highly involved in the pathogenesis of peptic ulcer disease. The relapse rate of duodenal ulcers can be markedly reduced by eradication of helicobacter pylori. Sample error in biopsy-dependent methods (culture, histology, rapid urease test) can cause false-negative results-due to the sometimes patchy colonization with helicobacter pylori. The high activity of urease liberates ammonia from urea stabilizing the pH in the direct environment of the bacterium. Radioactive or stable labeled urea is the substrate of urease in breath tests which noninvasively detect an acute infection without inspection of the mucosa. Serology can just reveal immunological contact not differentiating exposure in presence or past. Therefore, the noninvasive C-13-urea breath test offers an important diagnostic potential for the follow-up after helicobacter pylori eradication.