From the Guidelines
Helicobacter pylori (H. pylori) infection is associated with iron deficiency anemia. This type of anemia is caused by the bacteria damaging the stomach lining, reducing acid production, and impairing iron absorption, as well as potentially causing chronic gastritis and peptic ulcers that may bleed slowly, leading to blood loss anemia 1. The AGA suggests noninvasive testing for H pylori, followed by treatment if positive, over no testing, as treatment of H pylori infection may lead to improvement in iron deficiency 1. Key points to consider include:
- H pylori infection can decrease iron absorption by causing atrophic gastritis and hypochlorhydria 1
- Treatment of H pylori infection has been shown to lead to greater improvement in mean hemoglobin and ferritin levels compared to iron replacement alone 1
- Testing for H pylori, with treatment if positive, may assist in resolution of iron deficiency 1
From the Research
H pylori and Anemia
- H pylori infection has been linked to iron deficiency anemia in several studies 2, 3, 4.
- A meta-analysis of randomized controlled trials found that H pylori eradication improved hemoglobin, serum iron, and serum ferritin levels in patients with iron deficiency anemia 4.
- Another study found that H pylori infection was associated with reduced iron stores, and that anti-H pylori therapy may improve iron stores 2.
- However, a study published in 2019 found no evidence that H pylori infection was a cause of unexplained iron deficiency anemia, and that iron deficiency anemia resolved in most subjects regardless of H pylori treatment status 5.
Types of Anemia
- Iron deficiency anemia is the most common type of anemia associated with H pylori infection 2, 3, 4.
- H pylori infection may also be associated with other types of anemia, such as vitamin B12 deficiency anemia, due to malabsorption of essential nutrients 3.
Mechanisms of Anemia
- The biologic mechanism by which H pylori induces alterations in iron stores is not fully understood, but it may involve gastrointestinal blood loss, decreased absorption of dietary iron, and enhanced uptake of iron by the bacterium 2.
- H pylori infection may also modify intragastric pH, leading to malabsorption of essential nutrients, including iron and vitamin B12 3.