Iron deficiency anemia. Etiology, pathogenesis, diagnosis, treatment

Kamilė Burbaitė1, Justina Ramanavičiūtė1

1Lithuanian University of Health Sciences, Medical Academy, Faculty of Medicine

Abstract

Lack of iron- the most common eating disorder in the world. It is estimated that 30-50% of the world’s population has iron deficiency anemia, and most of these people live in developing countries. An adult person has an average of 2-6 g of iron, depending on body weight. Of these, 70 percent are erythrocytes in hemoglobin and 10 percent in enzymes and myoglobin, while circulating iron in plasma contains only 3-4 mg. Iron bound to ferritin in hepatocytes and macrophages (iron depots) accounts for 20 percent of total human iron. Anemia is not a disease by itself, it occurs for many reasons, so targeted treatment of this disease begins with finding the cause and eliminating it. The disease is caused by starvation, insufficient intake of iron with food, vegetarianism, copious loss of blood from the gastrointestinal tract and in women during menstruation, due to various diseases of the gastrointestinal tract, which interfere with the absorption of iron in the body. Iron deficiency anemia occurs when a change in blood tests is observed: decreased hemoglobin, microcytes, hypochromic erythrocytes, and decreased iron stores. Symptoms reflect hypoxic functioning due to decreased hemoglobin content and concentration in erythrocytes, which impairs the delivery of oxygen to tissues, resulting in insufficient provision of the body’s needs [1], [2].

Laboratory values corresponding to iron deficiency or iron deficiency anemia are: mean erythrocyte size (MCV) less than 80 fL, increased erythrocyte distribution width, decreased reticulocyte count, decreased ferritin, decreased serum iron, increased total iron binding capacity and decreased iron binding capacity saturation level [3].

Ferritin levels below 15 ng / ml are the only test results that are most indicative of iron deficiency in adults (less than 12 ng / ml in children) [3]. Although historically, oral iron supplements have been administered 2-3 times daily, more recent data suggest that once daily dosing may improve absorption and reduce gastrointestinal side effects. Iron intake is also increased by food intake, as vitamin C in foods improves iron absorption (coffee or tea that interfere with absorption should be avoided) [4].

In some patients, including those with inflammatory bowel disease, chronic kidney disease, or chronic heart failure, intravenous iron therapy may be considered. An indication for such treatment could also be the second or third trimester of pregnancy or any patient who is intolerant to or has impaired oral iron uptake [5], [6].

Keywords: iron deficiency, anemia, ferritin, transferrin, reticulocytes, hemoglobin, microcytic hypochromic erythrocytes.