Consequences of Splenectomy

The spleen is a vital organ and is used by the immune system for several critical functions and for this reason a splenectomy has serious and long-term consequences.  Most importantly, the treatment of all future infections becomes more complicated after splenectomy, because a key component of the body's normal defense system is not longer present.

The spleen is a soft, fist-sized purplish organ located behind and to the left of the stomach.  The spleen plays an important role not only in the immune system but also the circulatory system.  It helps filter substances from the blood: blood passing through the spleen travels through a maze of sponge-like spaces called sinusoids, where macrophages surround and destroy old or damaged blood cells.

The spleen also helps the body fight infection.  Macrophages in the spleen rid the blood of certain parasites and bacteria.  The spleen contains lymphocytes, which release special proteins into the blood.  These proteins, called antibodies, weaken or kill bacteria, viruses, and other organisms that cause infection.

Causes and Development

Surgeons sometimes remove a patient's spleen in a procedure called a splenectomy.  The spleen may be removed if it is damaged or overactive, or if the patient has cancer of the lymphatic system.  A damaged spleen can cause a serious loss of blood (for example, after an accident) and in extreme cases result in death.  In most cases, surgeons can repair a damaged spleen, and surgery is sometimes necessary to stop the bleeding.  The spleen may become overactive and filter useful substances from the blood, resulting in anemia, bleeding, or infection.  In some cases, a surgery improves or corrects the disorder.  Cancer of the lymphatic system may also affect the spleen, thus requiring surgical removal of the organ.

A splenectomy causes no noticeable ill effects in most patients.  In a few patients – especially children – the main risk is from infection, but this varies according to age.  Young children are at a higher risk of infection than adults.

The most common type of infection is caused by the bacterium Streptococcus pneumonia.  This can lead to pneumonia or progress to potentially fatal septicemia (blood poisoning).  Haemophilus influenza type b (Hib) is another bacterium which causes infections such as epiglottitis and meningitis in children.  A vaccine against Hib was introduced in 1993 and all children born after this date should have received it.  Although the risk of developing these infections is small, it is present for life.  If a person has no spleen, he or she is also at greater risk of developing an infection after being bitten by an animal or insect, and therefore at greater risk of catching diseases such as malaria.