Tissue staining for Helicobacter pylori in intestinal metaplasia: correlation with its extension and histochemical subtypes.

The role played by Helicobacter pylori (Hp) infection in the occurrence of non-cardial gastric adenocarcinoma is suggestive but still debated. This study aimed to evaluate: a) the prevalence of Helicobacter-like organisms in antral bioptic specimens of 291 patients with chronic gastritis with antral atrophy and different subtypes of intestinal metaplasia (IM); b) the presence of a possible different positive tissue staining for the bacteria in the complete and incomplete intestinal metaplasia. Of the 291 patients, 222 cases (76.3%) showed type I IM, 28 cases (9.6%) type II IM and 41 cases (14.1%) type III IM. Helicobacter-like organisms were found in 42.9% of cases and positive tissue staining rate appeared to be inversely related to the extension of IM (58.7% in IM extended in less than 30% of specimens, 30.2% in IM extended between 30% and 60%, 2.7% in IM exceeding 60% of the biopsed area). The inverse correlation between lower positive tissue staining for Helicobacter-like organisms and greater extension of IM was statistically significant (p < 0.001). Incomplete metaplasia appeared to be unrelated to age and associated with a lower positive tissue staining for Helicobacter-like organisms; among patients with type I metaplasia, 118/222 showed Hp-positive bioptic specimens, vs 7/69 of types II and III (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)