GASTRIC MUCOSAL MALONDIALDEHYDE AND ASCORBIC ACID IN H. PYLORI ASSOCIATED DISEASES AND THEIR RELATIONS TO HISTOPATHOLOGICAL CHANGES

Background and study aims: Oxygen free radicals play an important role in pathogenesis of many inflammatory and neoplastic diseases and a number of antioxidant defenses limiting this role. Helicobacter infection was found to increase the production of reactive oxygen species and was suggested to be responsible even partially for the increased malignant potential in these patients. The aim of the present study w as to assess the level of malondialdehyde (MDA), a marker of lipid peroxidation, and ascorbic acid, a natural antioxidant, in gastric mucosa in patients with II. pylori associated diseases with analysis of results in relation to severity ofH. pylori colonization and histopathological changes. Patients and methods: Eighty patients with dyspecsia (43 males 37 females) with a mean age of 35.7 ± 10.8 years were candidates for the present study. Complete blood count, fasting blood glucose, liver and kidney function tests were measured. Upper gastrointestinal endoscopy was performed. with multiple corpal antral biopsies which were examined for histopathology, II. pylori colonization, MDA, ascorbic acid and total vitamin C concentrations. Results: Mean values of MDA, ascorbic acid total vitamin C were higher in all patients studied and such elevation was significant in 11 pylori positive patients. II. pylori colonization was found in all patients with gastric ulcer duodenal ulcer (100%) and 59.5% of patients with gastritis with grade 3 colonization in 45.9% of patients with gastric ulcer 5.4% of patients with gastritis while none of patients with duodenal ulcer showed grade 3 colonization (0%). Chronic inflammation polymorph nuclear cell (PNC) infiltration were found in all patients w th gastritis, gastric ulcer and duodenal ulcer and the highe.;t incidence of grade 3 pattern of each was recorded in patients with gastric ulcer (75 56% respectively). Lymphoid follicles were noticed in 100% of H. pylori positive patients while intestinal metaplasia gastric dysplasia were recorded in small number of patients with II. pylori associated gastritis (0.09%), a large number of patients with gastric ulcer (18% 56% respectively) none of patients with duodenal ulcer (0%). Positive correlation was obtained between mean values of MDA, ascorbic acid and total vitamin C on one hand and grade of H. pylori colonization, grade of chronic inflammation PNC infitration on the other hand. Patients with intestinal metaplasia gastric dysplasia had significantly higher MDA insignificantly lower ascorbic acid and vitamin C in comparison to patients without. Conclusion: High levels of mucosal MDA, ascorbic acid and total vitamin C were recorded in H. pylori associated gastritis, gastric and duodenal ulcer and such elevation was correlated to severity of inflammation and H pylori colonization. Patients with gastric ulcer showed the highest abnormalities and the highest incidence of metaplasia and dysplasia. Patients with intestinal metaplasia and gastric dysplasia lack adequate antioxidant response to the elevated MDA levels, finding that might support the idea of a link between oxidative stress and development of precancerous changes in H. pylori associated gastrointestinal diseases.