Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get Started
About our e-newsletters
- Free e-newsletters
- Mayo Clinic expertise
- We do not share your e-mail address
Housecall, our weekly general-interest e-newsletter, keeps you up to date on a wide variety of health topics with timely, reliable, practical information, recipes, blogs, questions and answers with Mayo Clinic experts and more. Our biweekly topic-specific e-newsletters also include blogs, questions and answers with Mayo Clinic experts, and other useful information that will help you manage your health.
Housecall Archives
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Causes
By Mayo Clinic staff
Your spleen is tucked under your rib cage next to your stomach on the left side of your abdomen. It's a soft, spongy organ that performs several critical jobs and can be easily damaged. Among other things, your spleen:
- Filters out and destroys old and damaged blood cells
- Plays a key role in preventing infection by producing white blood cells called lymphocytes and acting as a first line of defense against invading pathogens
- Stores blood and platelets, the cells that help your blood clot
- May act as an intermediary between your immune system and your brain, leading researchers to speculate that they may one day be able to trigger the spleen's infection-fighting abilities by manipulating the nervous system
An enlarged spleen affects each of these vital functions. For instance, as your spleen grows larger, it begins to filter normal red blood cells as well as abnormal ones, reducing the number of healthy cells in your bloodstream. It also traps too many platelets. Eventually, excess blood cells and platelets can clog your spleen, interfering with its normal functioning. An enlarged spleen may even outgrow its own blood supply, which can damage or destroy sections of the organ.
What causes it?
A number of infections and diseases can contribute to an enlarged spleen, including:
- Viral infections, such as mononucleosis
- Bacterial infections, such as syphilis or an infection of your heart's inner lining (endocarditis)
- Parasitic infections, such as malaria
- Cirrhosis and other diseases affecting the liver
- Various types of hemolytic anemia — a condition characterized by premature destruction of red blood cells
- Blood cancers, such as leukemia and Hodgkin's disease
- Metabolic disorders, such as Gaucher's disease and Niemann-Pick disease
- Pressure on the veins in the spleen or liver or a blood clot in these veins
- Johnson HA, et al. Massive Splenomegaly. Surg Gynecol Obstet. 1989 Feb;168(2):131-7, http://www.ncbi.nlm.nih.gov/pubmed/2911790. Accessed July 15, 2008.
- Splenomegaly. Merck Manuals Online Medical Library. November 2005, http://www.merck.com/mmhe/sec14/ch179/ch179b.html. Accessed July 15, 2008.
- Patient Information for Spleen Removal (Splenectomy) from SAGES. The Society of American Gastrointestinal and Laparoscopic Surgeons, http://www.sages.org/sagespublication.php?doc=PI12.
- Chronic Myloproliferative Disorders. National Cancer Institute, http://cancernet.nci.nih.gov/templates/doc.aspx?viewid=0edcce21-e137-437f-82d6-7f81a60337e0&version=1&allpages=1. Accessed July 15, 2008.
- The Spleen. Journal of the American Medical Association. http://jama.ama-assn.org/cgi/reprint/294/20/2660.pdf. Accessed July 15, 2008.
- Martin MB, et al. Thalassemia and the Spleen. The Cooley's Anemia Foundation. http://www.cooleysanemia.org/updates/Spleen1.pdf. Accessed July 15, 2008.
- Splenomegaly. Merck Manuals Online Medical Library, http://www.merck.com/mmpe/sec11/ch138/ch138b.html. Accessed July 15, 2008.
