Your spleen is an organ that sits just below your left rib cage. Many conditions — including infections, liver disease and some cancers — can cause an enlarged spleen. An enlarged spleen is also known as splenomegaly (spleh-no-MEG-uh-lee).
An enlarged spleen usually doesn't cause symptoms. It's often discovered during a routine physical exam. A doctor usually can't feel the spleen in an adult unless it's enlarged. Imaging and blood tests can help identify the cause of an enlarged spleen.
Treatment for an enlarged spleen depends on what's causing it. Surgery to remove an enlarged spleen usually isn't needed, but sometimes it's recommended.
An enlarged spleen typically causes no signs or symptoms, but sometimes it causes:
See your doctor promptly if you have pain in your left upper belly, especially if it's severe or the pain gets worse when you take a deep breath.
A number of infections and diseases can cause an enlarged spleen. The enlargement might be temporary, depending on treatment. Contributing factors include:
Your spleen is tucked below your rib cage next to your stomach on the left side of your belly. Its size generally relates to your height, weight and sex.
This soft, spongy organ performs several critical jobs, such as:
An enlarged spleen affects each of these jobs. When it's enlarged, your spleen may not function as usual.
Anyone can develop an enlarged spleen at any age, but certain groups are at higher risk, including:
Potential complications of an enlarged spleen are:
An enlarged spleen is usually detected during a physical exam. Your doctor can often feel it by gently examining your left upper belly. However, in some people — especially those who are slender — a healthy, normal-sized spleen can sometimes be felt during an exam.
Your doctor might order these tests to confirm the diagnosis of an enlarged spleen:
Sometimes more testing is needed to find the cause of an enlarged spleen, including a bone marrow biopsy exam.
A sample of solid bone marrow may be removed in a procedure called a bone marrow biopsy. Or you might have a bone marrow aspiration, which removes the liquid portion of your marrow. Both procedures might be done at the same time.
Liquid and solid bone marrow samples are usually taken from the pelvis. A needle is inserted into the bone through an incision. You'll receive either a general or a local anesthetic before the test to ease discomfort.
A needle biopsy of the spleen is rare because of the risk of bleeding.
Your doctor might recommend surgery to remove your spleen (splenectomy) for diagnostic purposes when there's no identifiable cause for the enlargement. More often, the spleen is removed as treatment. After surgery to remove it, the spleen is examined under a microscope to check for possible lymphoma of the spleen.
Treatment for an enlarged spleen focuses on the what's causing it. For example, if you have a bacterial infection, treatment will include antibiotics.
If you have an enlarged spleen but don't have symptoms and the cause can't be found, your doctor might suggest watchful waiting. You see your doctor for reevaluation in 6 to 12 months or sooner if you develop symptoms.
If an enlarged spleen causes serious complications or the cause can't be identified or treated, surgery to remove your spleen (splenectomy) might be an option. In chronic or critical cases, surgery might offer the best hope for recovery.
Elective spleen removal requires careful consideration. You can live an active life without a spleen, but you're more likely to get serious or even life-threatening infections after spleen removal.
After spleen removal, certain steps can help reduce your risk of infection, including:
Avoid contact sports — such as soccer, football and hockey — and limit other activities as recommended to reduce the risk of a ruptured spleen.
It's also important to wear a seat belt. If you're in a car accident, a seat belt can help protect your spleen.
Finally, be sure to keep your vaccinations up to date because your risk of infection is increased. That means at least an annual flu shot, and a tetanus, diphtheria and pertussis booster every 10 years. Ask your doctor if you need other vaccines.
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