Educational Series: What the ferritin?

Iron deficiency, the most widespread nutritional deficiency and cause of anaemia worldwide, is common in children, adolescents and during pregnancy. Functional iron deficiency is also routinely encountered in several conditions, such as chronic kidney disease, heart failure and inflammatory bowel disease. This review emphasises the interpretation of iron studies, and the importance of appropriate investigations of iron deficiency anaemia; the critical role of iron supplementation in diverse patient populations; and the advantages of intravenous over oral iron therapy when oral iron replacement is inappropriate or when rapid repletion of iron stores is required.