Hypersplenism

What is hypersplenism?

Hypersplenism is when your spleen becomes overactive in doing its job. Its job is to filter out old and damaged cells from your bloodstream. When your spleen becomes overenthusiastic about filtering your blood, it removes too many blood cells too soon, leaving you with a deficit of blood cells (cytopenia).

How does this condition affect my body?

Hypersplenism may lead to a deficit of certain types of blood cells or all of them. You might have:

• Anemia: Low red blood cell count. Symptoms include feeling cold and tired.
• Leukopenia: Low white blood cell count. This can make you more prone to getting sick.
• Thrombocytopenia: Low platelet count. This can make you bleed and bruise more easily.

Hypersplenism can be mild to severe, and so can the deficit of blood cells you’re left with. Some people won’t notice the effects of hypersplenism and may not need treatment for it. In other cases, it can be a significant factor in your overall health — especially when it occurs with a serious underlying disease.

How does hypersplenism occur?

Hypersplenism occurs when your spleen becomes abnormally enlarged (splenomegaly). When your spleen enlarges, its blood volume increases. Your spleen retains a greater percentage of your total blood cells at one time. As it retains them, it filters and discards more of them, eventually even healthy ones.

Common causes of splenomegaly that may lead to hypersplenism include:

• Liver disease: Conditions affecting your liver, such as chronic hepatitis or cirrhosis, can cause pressure to build up in the blood vessels that run through your liver and spleen. This is called portal hypertension. It causes the blood volume in your spleen to increase and your spleen to swell.
• Infections: Viral infections such as mononucleosis and HIV, bacterial infections such as tuberculosis and endocarditis and parasitic infections such as malaria and toxoplasmosis stress the immune function of the spleen. They can cause it to overproduce antibodies and immune cells. The overproduction of cells (hyperplasia) adds to the overall volume of the spleen.
• Autoimmune diseases: Chronic inflammatory conditions such as lupus, sarcoidosis and rheumatoid arthritis can cause an overactive immune response and spleen hyperplasia (overproduction of cells).
• Cancer: Blood cancers such as leukemia or myeloproliferative neoplasms (MPNs) and lymphomas can infiltrate the spleen with foreign cells that continue to multiply.
• Blood disorders: Conditions such as hemolytic anemia and neutropenia that cause early destruction of red blood cells can overload the spleen, whose job is to remove them.
• Inherited metabolic disorders: Conditions that cause various substances to build up in your blood and store in your organs, such as Niemann-Pick disease, Gaucher disease and sickle cell disease, can infiltrate the spleen.

What are the symptoms of hypersplenism?

You may not notice symptoms with hypersplenism. If you do, you may have:

• Symptoms of an enlarged spleen: Your spleen may be sore (pain in your upper left abdomen) or you may notice that you can feel it with your hand, which you usually can’t. If your swollen spleen presses down on your stomach below, you may feel fuller sooner after eating.
• Symptoms of anemia: Red blood cells carry oxygen to your body tissues, so when you don’t have enough of them, your tissues become oxygen deprived. As a result, you might feel dizzy, weak or tired. You might get cold easily or get headaches, and your skin might look pale.

How is hypersplenism diagnosed?

A healthcare provider will look for evidence of splenomegaly and measure your blood cell levels. They may be able to feel your swollen spleen during a physical exam. They may also take an ultrasound to confirm it. A complete blood count will tell them which types of blood cells you are low in, and how low.

How is hypersplenism treated?

Hypersplenism is usually a side effect and an indicator of another, more important condition. If you haven’t yet been diagnosed or aren’t yet receiving treatment for that condition, your healthcare provider will focus on that first. They may need to order additional tests to determine the cause.

Treatment for hypersplenism itself will depend on how severe it is. It may include:

• Blood transfusion: Your provider will restore your low blood cell counts with donated blood.
• Low-dose radiation therapy or radiofrequency ablation: These are two methods healthcare providers use to target and destroy body tissues, such as tumors. They can treat hypersplenism by reducing your enlarged spleen to a more normal size. Your provider might suggest this if your hypersplenism is severe and if they can’t reduce it by treating your underlying condition.
• Splenectomy: In severe cases when other treatments haven’t worked, your provider might suggest removing part or all of your spleen. You can live without a spleen, but it does weaken your immune system. This may do more harm than good, depending on your underlying condition. For this reason, splenectomy is usually a last resort. If you do have one, your provider will recommend specific vaccines to protect you against common infections. In some cases, they may prescribe daily prophylactic (preventative) antibiotics to take after your splenectomy.

What can I expect if I have this condition?

Hypersplenism is treatable, but your prognosis will depend on your underlying condition. Some conditions are temporary, some are chronic (long-lasting) and some are progressive (long-lasting and worsening.) If hypersplenism causes cytopenia, you can restore your blood cell count with transfusion.

What is the difference between hypersplenism and splenomegaly?

Hypersplenism is a side effect of splenomegaly. Splenomegaly is when your spleen is abnormally enlarged. Many things can cause your spleen to enlarge and to become overactive, but hypersplenism doesn’t always occur. All overactive spleens are enlarged, but not all enlarged spleens are overactive.