The spleen acts as part of the immune system by filtering blood. Splenomegaly occurs when the spleen grows larger or becomes heavier.
Healthcare professionals consider splenomegaly when the spleen is anywhere from 12 to 20 centimeters (cm) (4.7 to 7.9 inches [in]) in length and weighs more than 400 grams (g) (0.88 pounds [lb]).
Massive splenomegaly occurs when the spleen is larger than 20 cm (7.9 in) or weighs more than 1,000 g (2.2 lb).
This article will discuss some potential causes and symptoms of splenomegaly, as well as the treatment options currently available.
Some of the most common causes of splenomegaly include:
- Blood-related disorders: Conditions such as leukemia, lymphoma, or myeloproliferative conditions can cause cancer cells to invade the spleen and multiply rapidly, thereby increasing the spleen’s size. An estimated 64% of massive splenomegaly cases are due to blood-related disorders.
- Liver diseases: Liver diseases such as cirrhosis or hepatitis can cause increased pressure in the liver that backs up to the spleen. As a result, the spleen starts to enlarge. Hepatosplenomegaly occurs when enlargement and swelling affect both the liver and the spleen.
- Spleen infections: Because the spleen is part of the immune system, infections such as mononucleosis, tuberculosis, bacterial endocarditis, or HIV can cause the spleen to enlarge.
Some less common causes of splenomegaly include:
- connective tissue disorders, including systemic lupus erythematosus and rheumatoid arthritis
- cytopenias, such as autoimmune hemolytic anemia or immune thrombocytopenia purpura
- infiltrative disorders, such as amyloidosis or sarcoidosis
- splenic congestion, including congestive heart failure and portal hypertension
- splenic sequestration, which includes conditions such as pediatric sickle cell disease and hemolytic anemias
- venous thrombosis, such as hepatic or portal vein thrombosis
- rare conditions, including Banti’s syndrome and wandering spleen
Regardless of the cause, splenomegaly is a rare condition. An estimated 2% of the population experiences splenomegaly in their lifetime.
Older individuals are slightly more at risk of developing the condition because the outer covering of the spleen, known as the capsule, becomes slightly thinner with age.
Splenomegaly may not always cause symptoms. However, if symptoms do occur, they may include:
- abdominal bloating
- feelings of abdominal fullness, even after eating only a small amount
- frequent infections
- discomfort or pain around the left ribs
- bleeding easily
However, the symptoms of splenomegaly often depend upon the underlying cause. For example, a person with splenomegaly related to cancer may experience:
- night sweats
- unexplained weight loss
However, a person who has splenomegaly related to an infection may experience different symptoms altogether. These may include:
- a general feeling of being unwell (malaise)
Meanwhile, a person with splenomegaly related to a blood disorder can have symptoms that include:
- easy bleeding
- easy bruising
- shortness of breath
A doctor will consider a person’s symptoms along with any known underlying medical conditions.
In most circumstances, a person cannot feel their spleen. However, a doctor may be able to feel an enlarged spleen just under the left side of the ribs.
To diagnose splenomegaly, a doctor will start by having the person describe their symptoms. They will also perform a physical examination to see whether or not they can feel an enlarged spleen.
A doctor who suspects splenomegaly will likely order laboratory and imaging tests. Some examples of these tests include:
- A complete blood count: This includes measurements of white and red blood cells and platelets. Having low counts of these three measurements may indicate splenomegaly.
- Imaging studies: Typically, these will include CT scans and ultrasounds.
- Liver function tests: Having high levels of liver enzymes such as AST and ALT may suggest splenomegaly.
Again, the tests a doctor orders may depend on the potential underlying cause.
Because other medical conditions tend to cause splenomegaly, treatment will usually start with addressing the underlying condition. For example, a person with splenomegaly related to sickle cell anemia will require blood transfusions or blood exchange transfusions.
In some cases, such as a rupture or cancer, a surgeon may have to remove a person’s spleen in a procedure known as splenectomy. Like the gallbladder or appendix, a person can live without their spleen. However, because the spleen contains so much blood, this type of surgery can be high risk due to excessive bleeding concerns.
While undergoing treatment for the underlying condition, a person should be very careful to avoid sustaining abdominal injuries. Trauma to an enlarged spleen can easily cause the spleen to rupture, which can lead to life threatening bleeding. For example, a person should avoid playing contact sports when they have splenomegaly to reduce their risk of injury.
Splenomegaly can lead to rupture of the spleen. This results in the need for surgery and often blood transfusions to restore blood volumes.
If a person has their spleen removed, they have a higher risk of some infection types. These include Streptococcus pneumoniae and Neisseria meningitidis.
The spleen usually carries immune cells that can help fight such illnesses. However, people who undergo splenectomy may require stronger antibiotics to fight infections than a person who has not had this surgery.
A person should see their doctor if they have any symptoms associated with splenomegaly — such as abdominal symptoms they cannot explain, including swelling, pain, or appetite loss — or can feel their spleen on their left side.
If a person has a known condition that leads to splenomegaly, they should be aware of the potential symptoms and call their doctor if they experience any of them.
Splenomegaly is a rare but potentially life threatening occurrence that can lead to splenic rupture.
The condition can develop due to several underlying medical conditions, ranging from blood disorders to liver disease.
If a person suspects that they have splenomegaly, they should see their doctor and take steps to protect against abdominal injury.