Iron deficiency anaemia

Iron deficiency anaemia is the most common anaemia worldwide. Iron is needed to make the haemoglobin in red blood cells, therefore a deficiency of iron leads to a reduction in red blood cells/haemoglobin i.e. anaemia. Iron deficiency anaemia has the highest incidence amongst preschool-age children. The main causes are excessive blood loss, inadequate dietary intake, poor intestinal absorption and increased iron requirements.

Epidemiology

• Globally, iron deficiency is the most common cause of anaemia
• Preschool-age children have the highest prevalence of iron deficiency anaemia

Causes

• Excessive blood loss: blood loss due to menorrhagia is the most common cause in pre-menopausal women, whereas gastrointestinal bleeding is the most common cause in men (always suspect colon cancer) and post-menopausal women.
• Inadequate dietary intake: as meat is a good source of iron, vegans and vegetarians are more likely to develop iron deficiency anaemia due to a lack of meat in their diet. However dark green leafy vegetables are another good source of iron, therefore people who don't eat meat can still receive enough iron through purely dietary sources.
• Poor intestinal absorption: conditions which affect the small intestine, such as coeliac disease, can prevent sufficient iron being absorbed.
• Increased iron requirements: children have increased iron demands during periods of rapid growth. Women also have increased demands during pregnancy as the baby will receive their iron supply from the mother. In addition, an increase in plasma volume during pregnancy causes iron deficiency anaemia through dilution i.e. the proportion of fluid in comparison to red blood cells increases.

Features

• Fatigue
• Shortness of breath on exertion
• Palpitations
• Pallor
• Nail changes: this includes koilonychia (spoon-shaped nails)
• Hair loss
• Atrophic glossitis
• Post-cricoid webs
• Angular stomatitis