For many people, the spleen is a bit of a mystery organ. Normally about the size of your fist, the spleen sits high in the left side of your abdomen near the top of your stomach. It houses large numbers of lymphocytes, a type of white blood cell that fights infections. The spleen also filters your blood, trapping and attacking bacteria and viruses, and removing and recycling old or deformed red blood cells. Although your spleen is protected by the rib cage, it is susceptible to traumatic injury. The spleen also commonly enlarges with a variety of infections and other noninfectious disorders. Marked enlargement or injury of the spleen can cause a variety of signs and symptoms. Spleen enlargement, or splenomegagly, generally causes more subtle and gradually developing signs and symptoms than a splenic injury.
Depending on how rapidly the spleen swells and how large it becomes, it's possible to have splenomegaly without obvious signs or symptoms. People who experience symptoms may notice mild, vague upper abdominal discomfort. Some people report pain in the left shoulder, which occurs due to irritation of the diaphragm -- the muscle separating the chest and abdominal cavities.
A markedly enlarged spleen encroaches on the stomach and often provokes a persistent feeling of fullness and an associated decrease in appetite. On physical examination, a doctor can usually feel a significantly enlarged spleen. Persons with an enlarged spleen often exhibit other signs and symptoms associated with the underlying cause of the enlargement, such as liver disease, an infection or a blood disorder.
An enlarged spleen sometimes becomes overactive, filtering out and destroying large numbers of red blood cells (RBCs), white blood cells (WBCs)and platelets -- cell particles that clump together to stop bleeding. Low levels of RBCs, WBCs and platelets are hallmark signs of hypersplenism. These levels usually drop gradually as the spleen enlarges and the bone marrow increases production to at least partially compensate for the increased destruction. For this reason, symptoms are often absent. In people with sickle cell disease, however, hypersplenism can develop relatively quickly and lead to weakness, shortness of breath and a rapid heart rate.
The spleen is the most commonly injured abdominal organ, usually as a result of blunt trauma due to an automobile accident, significant fall or contact sports. Signs and symptoms vary based on the severity of the damage and associated internal bleeding. Abdominal pain and tenderness are common and may be accompanied by left shoulder pain, a distended abdomen and nausea. When substantial bleeding occurs, signs and symptoms of shock often develop, including:
- Low blood pressure
- Rapid heart rate and breathing
- Cold, clammy skin
- Dizziness or fainting
- Blurry vision
- Anxiousness or restlessness
A splenic infarction refers to the death of some of the spleen tissue due to an interruption in blood supply. As with a spleen injury, signs and symptoms vary according to the extent of organ damage. Common signs and symptoms include sudden pain and tenderness in the upper left abdomen, left shoulder pain, fever, chills and a generalized feeling of being ill. A large spleen infarction can lead to splenic rupture and internal bleeding with signs and symptoms of shock.
Warnings and Precautions
Seek immediate medical evaluation if you suffer a blow to your abdomen and develop any signs or symptoms that might signal a spleen injury. Signs and symptoms might be delayed for hours to days, and can initially be mild and subtle -- but the condition is potentially life threatening.
Talk with your doctor if you have questions or concerns about possible spleen problems.
Reviewed and revised by: Tina M. St. John, M.D.
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