For example, screening for Hp is indicated in case of a history of ulcer or active ulcer, complicated or not, without previously documented Hp, chronic dyspepsia with long-term treatment with proton pump inhibitors (PPI) (>6 months), iron deficiency anemia with no known cause or resistant to oral iron treatment, and vitamin B12 deficiency with no etiology found. This evidence concerns the gene HP and Iron deficiency anemia.