- Take the Tummy Trouble Quiz
- Digestive Disease Myths Slideshow Pictures
- Ulcerative Colitis Slideshow
- Patient Comments: Enlarged Spleen - Cause
- Patient Comments: Enlarged Spleen - Symptoms
- Patient Comments: Enlarged Spleen - Treatment
- Patient Comments: Enlarged Spleen - Experience
- Enlarged spleen (splenomegaly) facts
- What is the spleen, and what does it do (function)?
- What type of pain, and where is the pain located with an enlarged spleen?
- What are other signs and symptoms of an enlarged spleen?
- Where is the spleen, and what does it look like?
- What are the causes of an enlarged spleen?
- How is the diagnosis of an enlarged spleen made?
- What is the treatment for an enlarged spleen?
- What complications are associated with an enlarged spleen?
- Can an enlarged spleen be prevented?
- What is the prognosis for someone with an enlarged spleen?
What are the causes of an enlarged spleen?
The spleen will enlarge when it performs more of its duties to filter blood or to manufacture blood cells. Therefore, any disease or condition that damages red blood cells, and requires them to be filtered and removed from the blood stream, will cause the spleen to become larger.
Conditions such as hemolytic anemia, where red blood cells are damaged and broken down (hemolyzed) can cause the spleen to enlarge. Misshapen red blood cells, like those found in sickle cell disease, thalassemia, and spherocytosis, may be damaged when they try to squeeze through small capillary blood vessels. These damaged red blood cells need to be culled from the bloodstream and are filtered out by the spleen.
Decreased blood flow
The spleen will enlarge if there is a decrease in blood flow through the splenic vein. This may cause spleen congestion and enlargement. This situation may be associated with liver disease and portal hypertension. Damage to liver cells makes it difficult for blood to flow normally, and as blood backs up in the portal vein system, it may also affect pressure in the splenic vein. The decreased ability of blood to drain from the spleen causes it to become congested and grow larger. People with congestive heart failure may have an enlarged liver and spleen because of poor blood flow to and from the heart.
Other cancers can spread or metastasize to the spleen and cause it to enlarge.
Certain metabolic diseases may cause the spleen to enlarge, including Hurler Syndrome, Gaucher disease and Niemann-Pick Disease.
In sarcoidosis and amyloidosis the spleen can be involved and become enlarged with the abnormal protein deposits.
Some infections may cause splenomegaly including:
- Infectious mononucleosis caused by the Epstein-Barr virus
- Viral hepatitis
Trauma, for example, from a car accident, can damage the spleen.
How is the diagnosis of an enlarged spleen made?
An enlarged spleen is most often found on physical examination. Either the health care practitioner is looking for an enlarged spleen because of a diagnosis that has already been made, or it is found incidentally when initially examining a patient (and it then serves as a clue to an underlying diagnosis).
With its location protected beneath the left lower ribs, a normal spleen is usually not felt on physical exam, except in some unusually thin individuals. As it enlarges, the spleen grows from the left upper quadrant of the abdomen towards the umbilicus (the belly button). Sometimes the doctor will ask the patient to roll on their right side to better attempt to feel the spleen. An enlarged spleen may not be felt in obese patients.
On occasion, an enlarged spleen may be diagnosed by plain X-ray, ultrasound, abdominal CT scan, or MRI (magnetic resonance imaging).