Diagnosis

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:

• Blood tests, such as a complete blood count to check the number of red blood cells, white blood cells and platelets in your system and liver function
• Ultrasound or CT scan to help determine the size of your spleen and whether it's crowding other organs
• MRI to trace blood flow through the spleen

Finding the cause

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.