ABSTRACT
The impact of Schistosoma mansoni and Fasciola parasitic infections on H. pylori induced pathogenesis was studied in 20 patients exclusively having H. pylori infection alone. The patients were compared to 20 patients having schistosomiasis mansoni co-infected with H. pylori and to another 20 patients having fascioliasis co-infected with H. pylori. 15 patients exclusively having schistosomiasis mansoni alone and 15 patients exclusively having fascioliasis alone were also included in the study. All patients were subjected to thorough medical examination, parasitological, endoscopic and histopathological studies. The results showed that severe gastritis was significantly more common in the patients exclusively infected with H. pylori alone. Chronic atrophic gastritis and intestinal metaplasia or precancerous lesions were present in patients with exclusively H. pylori infection. We may conclude that the concomitant of parasitic diseases with H. pylori infection probably reduce the gastroduodenal pathogenesis through indirect immune response