[Human iron deficiency].
Iron deficiency is the most widespread nutritional disorder in the world, affecting an estimated 1.2 billion people. Its prevalence is particularly high in developing countries (Africa, Asia, South America), but iron deficiency remains a public health problem in industrialised countries. Three successive stages of iron deficiency can be distinguished: iron store depletion, iron-deficient erythropoesis and iron-deficiency anemia. Investigations of iron deficiency should take into account the clinical background. In groups at risk (infants and children, women of childbearing age, pregnant women), management is limited to nutritional inquiries, gynecological examination, and oral iron supplementation. In men and post-menopausal women, iron deficiency is assumed to result from occult gastrointestinal bleeding, and this may necessitate upper and lower gastrointestinal endoscopy. Benign lesions are more frequently found in the upper digestive tract than in the lower digestive tract. When these investigations are negative and iron supplementation is unsuccessful, video-capsule endoscopy is recommended. Oral iron treatment is based on ferrous salts (200 mg/d). The duration of treatment depends on the severity of iron deficiency, ranging from three months for iron store depletion and iron-deficient erythropeisis to six months for iron-deficiency anemia.