[Comparable evaluation of usefulness of traditional methods and polymerase chain reaction technique in detection of Helicobacter pylori infection].

UNLABELLED: H. pylori is a well recognized pathogenic factor of chronic gastritis and class I carcinogen. Specimens are collected on gastroscopy performed due to clinical symptoms suggesting upper alimentary tract organic disease for pathomorphological examinations and for the estimation of the presence of H. pylori infection in urease test, histological examination in Giemsa staining method or in a culture. The aim of the project was to compare the detection of H. pylori in gastric mucosa in children by conventional method and polymerase chain reaction technique (PCR).

MATERIAL AND METHODS: The study comprised 137 children and adolescents, aged 5-18 years (mean 13.2 years), in whom basing on the evaluation of the level of serum anti-H.pylori antibodies (ELISA), urease test and histological examination (HE), H. pylori infection was diagnosed or excluded. H. pylori genes: ureA, vacA, cagA were identified in gastric mucosa specimens with PCR method.

RESULTS: On the grounds of standard methods H. pylori was detected in 86 (62.8%) and excluded in 51 (37.2%) children. UreA gene was detected in gastric mucosa in 82 (95.3%) children with H. pylori (Hp+) and in 8 (15.7%) without H. pylori (Hp-) infection (p < 0.001). CagA H. pylori gene was identified in 21 (24.4%) children from Hp+ group and in 1 (2%) from Hp- group (p < 0.001), and vacA gene in 23 (26.7%) and 6 (11.8%) (NS), respectively. H. pylori strains type I (cagA+/vacA+) were found in gastric mucosa of 15 (17.4%) Hp+ patients. CONCLUSIONS. Testing of H. pylori genes (particularly ureA gene) with PCR technique in mucosa bioptates enables to diagnose H. pylori infection even in patients with the infection not detected with standard methods.