What is iron-deficiency anaemia? And what causes it?

Iron-deficiency anaemia is a haematological syndrome characterised by the abnormal synthesis of haemoglobin, due to either a deficiency of iron or over-absorption. It is most commonly brought on by blood loss or a diet lacking in iron. Globally, 1.5 billion people suffer from iron deficiency: of these, nearly 1.2 billion suffer from iron-deficiency anaemia.


Loss of blood

Adults tend to suffer from iron deficiency following loss of blood: constant small losses or chronic concealed bleeding (5-10ml daily); a single massive loss (exceeding what can be replenished easily); or repeated considerable bleeding (after which iron stock lacks time to be restored).

Blood loss leading to post-hemorrhagic iron-deficiency anaemia is most commonly caused by metrorrhagia (bleeding from the alimentary canal); it is rare to develop anaemia from nosebleeds, tooth-extraction, pulmonary, nephritic or traumatic bleeding or other kinds of blood loss.

According to statistical data, 20-30 percent of women of childbearing age have a latent iron deficiency, while 8-10 percent have iron-deficiency anaemia. Metrorrhagia increases the volume of blood loss among women and cases of iron-deficiency.

The second most common cause of post-hemorrhagic iron-deficiency anaemia is blood loss from the alimentary canal of latent character. This is difficult to diagnose but is the main cause of anaemia among men, often linked to disease of the digestive organs or other illness. Abnormal iron levels may be accompanied by infections of the oesophagus or stomach, bleeding gastro-duodenal ulcers, or chronic infectious and inflammatory diseases of the alimentary canal.

Latent blood loss can be hard to diagnose, including when caused by gastro-oesophageal hernia, oesophageal varicose veins, rectal varices (dilation of vessels due to portal hypertension), haemorrhoids or tumours. Pulmonary bleeding is a rare cause of iron deficiency. Another cause may by bleeding from the kidneys or urinary tracts (accompanied by stones or a tumour). In certain cases, blood loss comes from a different location or may be linked to a blood disorder or the destruction of blood vessels through inflammation (vasculitis) or collagen diseases. Sometimes, iron-deficiency anaemia is caused by blood loss, and can develop in babies and toddlers. Children are more sensitive to blood loss than adults. Newborns are vulnerable to blood loss from the placenta, especially through damage during caesarean delivery.

An unbalanced diet

Iron deficiency of alimentary origin can develop in children or adults whose diet lacks sufficient iron. It may be observed in those suffering from chronic malnutrition or starvation, or in those whose diet is simply too limited, being based largely on fats and sugar. Several physiological conditions require the body to raise its absorption of iron, such as pregnancy and lactation, and during periods of growth (in children). The latter is most acute in the first year of life, and during puberty. Girls have an additional need, due to menstruation.

Iron-deficiency anaemia is most common during infancy and old age, accompanied by infectious or inflammatory diseases, burns, tumours, or reduced ability to absorb and retain iron levels within the body. Iron-deficiency anaemia has two periods: a period of latency and a period of obvious anaemia, caused by iron deficiency. During latency, clinical symptoms of iron-deficiency anaemia may appear less prominently, with patients displaying a feeling of weakness and indisposition, with impaired performance. They may lack appetite, have a dry or prickling tongue, have difficulty swallowing (feeling as if a foreign body is in the throat), have palpitations or feel short of breath.

Lesser symptoms of iron deficiency may include wasting of the taste-buds (atrophied lingual papillae), inflammation of the lips (including angular cheilitis), dry skin and hair, or brittle nails. Non-manifest iron deficiency can be the only sign of lack of iron. Loss of body performance may not be so much a consequence of anaemia as directly a consequence of lack of iron: patients may be weak and easily fatigued, with difficulty holding concentration and prone to sleepiness, headaches and dizziness. In acute cases, fainting may occur. These complaints tend not to depend upon the degree of anaemia but upon how long a patient has been suffering from the disease and their age.

Iron-deficiency anaemia is characterised by changes in the condition of skin, nails and hair. The skin is usually pale, sometimes with a light green shade (chlorosis) but with a quick ability to blush. Dry skin is also common, with peeling and chapping. Hair loses its shine, becoming grey and thin, breaking easily, and turning grey quickly. Nails become thin and flat, flaking and breaking, with, striations and loss of shine; they may even become spoon-shaped.

Prevention

Monitor your blood level, ensure a diet high in iron (including meat, and perhaps liver), take iron supplements (especially if you are in a ‘risk group’) and remove sources of blood loss.