ABSTRACT
BACKGROUND: Many individuals are infected with the bacterium Helicobacter pylori. Some develop ulcers or mucosal atrophy. AIMS: To correlate the histological characteristics of the H. pylori -induced gastritis to the immunoblot pattern of the H. pylori infection and to compare the presence of H. pylori bacteria in tissue specimens with ELISA serology and immunoblot analysis. METHODS: One hundred and sixty-six consecutive patients were referred to gastroscopy. Forty patients were excluded for various reasons and 126 were included in the study. RESULTS: Twenty-three patients had ulcerations and 25 erosions. Ninety-two (73%) had a chronic gastritis and in 90 (71%) it involved both the antrum and corpus. Ninety-one (72%), of whom 96% had a chronic gastritis, had visible bacteria in the tissue specimens, used as the 'gold standard' for the detection of infection. In patients with chronic gastritis 65 (70%) had positive H. pylori ELISA serology, 27 (30%) had negative H. pylori ELISA, while 76 (83%) had a positive immunoblot pattern. The ELISA positive patients had more advanced chronic gastritis but a lower frequency of metaplasia and atrophy. Acute inflammatory activity in the chronic gastritis had a high immunoreactivity to 120 kDa (CagA) protein and was significantly correlated to antibody reactivity to proteins in the 53-65 kDa range (heat shock proteins) and to a 43 kDa subunit. Metaplasia and atrophy in antrum was associated with a 62 kDa protein band. CONCLUSION: Almost all H. pylori-infected patients had a pangastritis, visible in both antrum and corpus. Acute inflammatory activity in the chronic gastritis and the presence of metaplasia and atrophy in antrum were associated with a specific immunoblot pattern, indicating infection with more virulent strains. Immunoblot analysis had a better sensitivity than ELISA H. pylori serology.
