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Enlarged Spleen

(Splenomegaly)

By

Harry S. Jacob

, MD, DHC, University of Minnesota Medical School

Last full review/revision Jan 2020| Content last modified Jan 2020
Click here for the Professional Version
Topic Resources

An enlarged spleen is not a disease in itself but the result of an underlying disorder. Many disorders can make the spleen enlarge.

  • Many disorders, including infections, anemias, and cancers, can cause an enlarged spleen.

  • Symptoms are usually not very specific but can include fullness or pain in the upper left abdomen or back.

  • Usually doctors can feel an enlarged spleen, but ultrasonography and other imaging tests may be used to determine how large the spleen is.

  • Treating the disorder that is causing the spleen to enlarge usually takes care of the problem, but sometimes the spleen must be removed.

To pinpoint the cause of an enlarged spleen, doctors must consider disorders ranging from chronic infections to blood cancers.

Did You Know...

  • An enlarged spleen is not a disease itself but the result of an underlying disorder.

An enlarged spleen may outgrow its own blood supply. When parts of the spleen do not get enough blood, they may become damaged, causing them to bleed or die.

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Causes of an Enlarged Spleen

Category

Specific Cause

Anemias

Blood cancers and myeloproliferative neoplasms

Infections

Storage diseases

Other causes

  • Blood clot in a vein from the spleen or to the liver

  • Cysts in the spleen

  • External pressure on veins from the spleen or to the liver

  • Felty syndrome (a subset of people with rheumatoid arthritis who also develop low white blood cell count and an enlarged spleen)

  • Hemophagocytic lymphohistiocytosis

  • Langerhans cell histiocytosis (formerly called Hand-Schüller-Christian disease and Letterer-Siwe disease)

Hypersplenism

The spleen normally removes old and/or damaged red blood cells from the bloodstream. However, when the spleen enlarges, it traps and stores an excessive number of red blood cells, causing anemia. Sometimes, the spleen also destroys white blood cells and/or platelets causing a low white blood cell count (leukopenia) and a low platelet count (thrombocytopenia). This process creates a vicious circle: the more cells the spleen traps, the larger it grows, and the larger it grows, the more blood cells it traps and destroys.

Symptoms

An enlarged spleen does not cause many symptoms, and the symptoms that it does cause may be mistaken for many other medical conditions. Because the enlarged spleen lies next to the stomach and sometimes presses against it, people may feel full after eating a small snack or even without eating. People may also have abdominal or back pain in the area of the spleen in the upper left part of the abdomen or the left side of the back. The pain may spread to the left shoulder, especially if parts of the spleen do not get enough blood and start to die.

If hypersplenism causes severe anemia, people may be tired and short of breath. People may also have frequent infections as a result of too few white blood cells, and the tendency to bleed as a result of too few platelets.

Diagnosis

  • Imaging of the abdomen

  • Blood tests

Doctors may suspect that the spleen is enlarged when people complain of fullness or pain in the upper left portion of the abdomen or back. Usually, doctors can feel an enlarged spleen during a physical examination.

An x-ray of the abdomen done for other reasons may also show that the spleen is enlarged. Ultrasonography or computed tomography (CT) is usually needed to determine how large the spleen is and whether it is pressing on other organs. Magnetic resonance imaging (MRI) provides similar information and also traces blood flow through the spleen. Other specialized scanning techniques use mildly radioactive particles to assess the spleen’s size and function and to determine whether it is accumulating or destroying large numbers of blood cells.

Blood tests show decreased numbers of red blood cells, white blood cells, and platelets. When blood cells are examined under a microscope, their shape and size may provide clues to the cause of the spleen enlargement. An examination of bone marrow may show cancer of the blood cells (such as leukemia or lymphoma) or an accumulation of unwanted substances (such as occurs in storage diseases). Blood protein measurement can determine whether other conditions are present that can cause the spleen to enlarge, such as amyloidosis, sarcoidosis, malaria, visceral leishmaniasis, brucellosis, and tuberculosis. Liver tests help determine whether the liver is also diseased.

Doctors cannot easily remove a sample of the spleen for examination because inserting a needle or cutting spleen tissue may cause uncontrollable bleeding. If an enlarged spleen is removed during surgery to diagnose or treat certain diseases, the spleen is sent to a laboratory, where the cause of enlargement can usually be determined.

Treatment

  • Treatment of the underlying disorder

  • Sometimes removal of the spleen

When possible, doctors treat the underlying disorder that caused the enlarged spleen. People with an enlarged spleen should avoid contact sports because an enlarged spleen is more likely to tear, causing uncontrollable bleeding.

Did You Know...

  • People with an enlarged spleen need to avoid contact sports because the spleen is at risk of tearing, causing uncontrollable bleeding.

The spleen may need to be surgically removed if hypersplenism causes severe problems. Surgical removal of the spleen (splenectomy) should be avoided whenever possible because it can cause problems, including an increased susceptibility to infections by certain bacteria. However, the risks are worth taking in certain critical situations:

  • When the spleen destroys red blood cells so rapidly that severe anemia develops

  • When the spleen so depletes stores of white blood cells that infection is likely

  • When the spleen so depletes stores of platelets that bleeding is likely

  • When the spleen is so large that it causes pain or puts pressure on other organs or causes early feelings of fullness after eating only a small amount

  • When the spleen is so large that parts of it bleed or die

As an alternative to surgery, radiation therapy can sometimes be used to shrink the spleen.

People who have had their spleen removed need to be vaccinated against infections caused by Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. They should also make sure they receive the influenza vaccine every year, as is now recommended for all people.

After splenectomy, people are particularly susceptible to severe sepsis, particularly if they regularly come into contact with children, and they may have to take antibiotics daily to prevent infections.

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