The Role of Helicobacter pylori Infection in Iron Deficiency and B₁₂ Deficiency Anemia

Aim: to review the current literature on the potential link between Helicobacter pylori (H. pylori) infection and iron deficiency and vitamin B₁₂ deficiency anemia.

Key points. Published studies have shown that iron deficiency anemia of unknown cause may be due to H. pylori infection, especially in pediatric practice. This infection can lead to impaired iron absorption through various mechanisms. Eradicating H. pylori infection can contribute to restoring normal red blood cell parameters. Additionally, patients infected with H. pylori have lower blood levels of vitamin B₁₂ compared to uninfected individuals. The mechanisms contributing to impaired vitamin B₁₂ absorption in patients with H. pylori infection may be associated with the progression of multifocal atrophic gastritis, as well as the production of antibodies against parietal cells and intrinsic factor. Many national gastroenterology societies and consensus meetings recommend testing for H. pylori infection patients with iron deficiency anemia or B₁₂ deficiency anemia of unknown origin and, if positive, eradicating it.

Conclusion. There is a positive association between H. pylori infection and the development of unexplained iron deficiency anemia. The relationship between H. pylori infection and vitamin B₁₂ deficiency anemia has not been sufficiently studied and requires further research.

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