Helicobacter pylori infection and blood group antigens: lack of clinical association.

Objectives : Blood group antigens traditionally have been associated with a risk of developing peptic ulcer and gastric cancer. Helicobacter pylori is a bacterium associated with chronic active gastritis and ulcer disease, and its attachment to gastric mucosa was recently shown in vitro to be mediated by blood group Lewis b and H antigens. This study was designed to test the clinical relevance of this laboratory observation in patients undergoing endoscopy and gastric biopsy. Methods : Blood group phenotypes and gastric biopsies for H. pylori and histology were determined and correlated in 384 patients undergoing upper endoscopy. Blood from healthy blood donors was tested for the same blood group antigens and used as a control group. Results : The distribution of blood groups ABO, Lewis, Rhesus, and MN was similar among the patients undergoing endoscopy and a control group of 2369 healthy blood donors from the same geographic area. There was no correlation between H. pylori infection or the H. pylori-associated diseases, peptic ulcer or chronic active gastritis, with any blood group phenotype, including Lewis b , blood group O, or both. Conclusion: No in vivo correlation between H. pylori infection or disease and Lewis b or H antigen could be demonstrated. Moreover, patients with H. pylori infection and disease have a distribution of blood group antigens similar to a control population.