[Helicobacter pylori infection is not associated with pernicious anemia in Japan].

At present, the etiologic relationship between pernicious anemia and H. pylori infection remains unknown because different rates of positivity have been reported. To investigate the relationship of these two entities, 16 Japanese patients diagnosed with pernicious anemia were examined for H. pylori infection. Serological tests for H. pylori-IgG antibody and gastric biopsy were performed. These 16 patients ranged in age from 34 to 93 years, with a mean age of 68.1 years. They were all negative for H. pylori-IgG antibody and H. pylori on gastric biopsy. Considering that the H. pylori-positive rate in the Japanese population of the same age (60 years) is 70-80%, the findings of this study suggest that the rate of H. pylori positivity in patients with pernicious anemia is low.