Splenomegaly means enlargement of the spleen. The spleen is located on the left side of the abdomen. It can be considered as two organs in one, since it:

• Filters the blood and removes abnormal cells, such as old and defective red blood cells.
• Produces disease-fighting components of the immune system, including antibodies and lymphocytes.

The healthy adult spleen weighs around 200g. However, a variety of disorders can cause the spleen to enlarge, sometimes to 2kg or more. Any conditions that cause a rapid breakdown of blood cells, such as any of the haemolytic anaemias, can place great strain on the spleen and make it enlarge. Other causes of splenomegaly include infections, liver disease and some cancers.

• Cirrhosis of the liver – which can increase the blood pressure inside the vessels of the spleen.
• Cystic fibrosis – a genetic disorder, characterised by excessive mucus production, particularly in the lungs and pancreas.
• Cytomegalovirus – a common viral infection that causes mild, flu-like symptoms.
• Glandular fever – an infection caused by the Epstein-Barr virus.
• Haemolytic anaemiassuch as thalassaemia, a genetic disorder that affects the production of the oxygen-carrying protein in red blood cells (haemoglobin).
• Hodgkin’s disease – cancer of the lymphatic system.
• Leukaemia – cancer of the bone marrow that affects the blood cells.
• Lymphoma – cancer of the lymph nodes of the lymphatic system.
• Malaria – a parasite transmitted to humans by the bite of infected mosquitoes.

• Enlarged spleen, which can be felt by palpating the abdomen
• Other symptoms, depending on the cause.

• Physical examination
• Ultrasound or abdominal x-ray
• Computed tomography (CT) scan
• Blood tests, to check for underlying disorders.