WHAT IS ANAEMIA?

Anaemia is a condition that results from a lack of healthy red blood cells in your body. All the cells in your body need oxygen, which is carried from your lungs to tissues throughout the body by the red blood cells. Haemoglobin, a protein in red blood cells, binds to oxygen and transports it. If haemoglobin is reduced due to a decreased number of red blood cells, anaemia results.

The most common symptom of anaemia is fatigue (excessive tiredness, exhaustion). Other symptoms include:

• shortness of breath
• pale skin
• heart palpitations
• noises in the ear
• thirst
• weight loss
• memory problems
• and jaundice (yellowish skin).

Preventing anaemia - the key players

Red blood cells

Blood has many functions in the body to help keep you alive and healthy. It transports oxygen from your lungs to your tissues via blood vessels, and waste products like carbon dioxide from your tissues to your lungs. Red cells are just one component in your blood, and they are made in your bone marrow starting as primitive, immature cells gradually maturing into fully functional cells. Red blood cells are continually produced and broken down. They last about 120 days in your bloodstream, and are then removed by the spleen. A shortage of healthy red blood cells leads to anaemia.

Haemoglobin

Haemoglobin, the main component of red blood cells, is an iron-containing protein that binds oxygen and transports it from your lungs to the rest of your body. Haemoglobin also transports carbon dioxide back to the lungs to be removed. Many toxic substances can alter the haemoglobin so that it does not bind oxygen correctly. If something causes a lowered red blood cell supply, and thus a shortage of haemoglobin, anaemia can develop.

Bone marrow

Your bone marrow, the spongy internal core of most bones, produces blood cells, supplying the required number of each type of cell (red cells, white cells and platelets). Your bone marrow increases production of red blood cells and platelets during, for example, bleeding. Erythropoietin, a hormone produced in the kidneys regulates the manufacture of red blood cells. If red cell production fails, anaemia occurs.

Kidneys

Healthy kidneys produce erythropoietin, a hormone that stimulates the formation of new red blood cells. Erythropoietin controls the production of red blood cells. In kidney failure, erythropoietin production is reduced, and the production of red blood cells falls, resulting in anaemia.

What causes anaemia?

Anaemia occurs most commonly when one of three things happens.

Red blood cell production decreases for some reason. The commonest cause is iron deficiency. Less common is a condition called thalassaemia (an inherited disease found most often in people of Mediterranean background). Also anaemia is associated with some drugs such as those used in chemotherapy for cancer.

Red blood cell destruction increases. This happens in infections, with patients receiving chemotherapy for cancer, autoimmune disorders such as rheumatoid arthritis, or HIV/AIDS, metabolic disorders and haemoglobin defects (e.g. sickle cell anaemia).

Blood loss occurs. This may be from trauma, excessive menstruation, surgery, or from slow bleeding over a long period of time (e.g. from a stomach ulcer).

Less commonly, alcohol, some drugs and certain chronic diseases (e.g. kidney disease, cancer, liver disease, systemic lupus erythematosus and some infections (e.g. pneumonia)) can cause anaemia.