Spleen Disorders

The spleen is a soft, oval organ that is about the size of a paperback book and is located in the left upper quadrant of the abdomen. It lies completely beneath the ribs and is surrounded by the stomach, pancreas and kidney.

Spleen History

For many years it was thought that the spleen was an unnecessary organ, like the appendix. Indeed, Hippocrates thought it was the source of black bile and Galen wrote it was "an organ full of mystery." Therefore, the spleen was removed whenever it was injured. In the Middle Ages it was removed as a way to rid the body of evil humors.

Since nothing usually happened when the spleen was removed, the concept that the spleen served no important role was maintained until the 1950s. It was then shown that the spleen was an important organ in preventing serious, overwhelming infection.

What Does the Spleen Do?

The spleen clears the blood of old red blood cells and platelets.  Red blood cells carry oxygen in the blood.  Platelets are the tiny cells that form the second line of defense against bleeding. When a blood vessel is cut, the blood vessel contracts to stop, or at least diminish, the bleeding.  Next, platelets clump at the site of injury to form a plug that temporarily stops the bleeding.  Finally, clotting factors in the blood are activated to help the platelets form the clot.

The spleen also produces antibodies that help fight bacterial infections.  Most important are the antibodies it produces against polysaccharide encapsulated (sugar coated) bacteria, such as pneumococcus, meningococcus and hemophilus.

Is There Any Risk to Not Having a Spleen?

Yes. The spleen is an important organ in preventing serious, overwhelming infection by gram positive, encapsulated bacteria, like pneumococcus, meningococcus and hemophilus, that are often lethal in children. In addition, it serves as the body's filter for a variety of particles that are present in the blood. Infection occurring after splenectomy was coined overwhelming postsplenectomy infection (OPSI) and until the 1980s was though to only occur in children. Today, it is recognized that OPSI can occur in both children and adults.

Fortunately, the risk of OPSI is very small. It is estimated to occur in 0.6% of adults who have had a splenectomy and 3% of children. This incidence may be higher if the reason for removing the spleen was for a disease of the spleen rather than for injury. Because the incidence is significantly higher in children, splenectomy is not performed unless absolutely necessary until adulthood. Furthermore, every effort is made during surgery for injuries to the spleen to preserve at least a portion of it.

Reducing the Risk

Here are some main ways to prevent OPSI:

• Undergo vaccination against pneumococcus and meningococcus prior to splenectomy when possible. While this is not possible when the need for splenectomy arises from an emergency, such as a car accident, it is feasible in all elective splenectomies. Although vaccination is not proven to reduce OPSI, it is believed that this will work. It can not eliminate the risk, however, because there are varieties of these bacteria that are not covered by the vaccination.
• Take penicillin or erythromycin as soon as a fever (greater than 100º F) or symptoms of a cold- or flu-like illness develops. This should prevent the infection from getting out of control. 
  Immediately call your physician and let him or her know.  This will help to prevent the infection from getting out of control. 
• Wear a Medic Alert bracelet.