No abstract

Objective: The primary objective of this study was to investigate five readily available methods for the diagnosis of Helicobacter pylori infection (both invasive and non-invasive) in order to establish the local definition of the disease in our hospital because of the regional variations in the prevalence, strains of organism and antibiotic susceptibility. Methods: Two histological methods (HE and immunohistochemistry, IHC) and microbiological methods (culture, urease test and Gram stain of tissue smears) for processing gastric antral biopsies were compared in a prospective study in 115 consecutive patients. H. pylori positivity by these methods was correlated with histopathological changes in the antral biopsies. Susceptibility of the H. pylori isolates to various antibiotics was performed by the modified disc diffusion test. Results: There was no significant difference between HE and IHC in the demonstration of H. pylori. Using culture as the ‘gold standard’ for specificity, both had specificity of 91 and 86%, respectively. However, when HE was used as a standard for sensitivity, the other methods had the following sensitivities: culture 69%, Gram stain 86%, biopsy urease 85%, and IHC 91%. Higher density of H. pylori infection correlated with higher culture positivity and more with the presence of active chronic gastritis than with chronic inactive gastritis. Of the antibiotics tested, only metronidazole showed appreciable resistance against the H. pylori isolates. Conclusion: We recommended the use of HE and culture in the definition of H. pylori infection at the local level, together with drug sensitivity testing to ensure an appropriate eradication strategy.