Splenomegaly (Enlarged Spleen)
An enlarged spleen, usually a sign of another condition
Quick Facts
- Type: Sign of an underlying condition
- Location: Upper left abdomen, under the ribs
- Common causes: Infections, liver disease, blood disorders
- Key risk: Rupture after injury
Overview
The spleen is a fist-sized organ tucked under the rib cage on the upper left side of the abdomen. It filters the blood, helps fight infection, and removes old or damaged blood cells. Splenomegaly means the spleen has become larger than normal.
An enlarged spleen is usually not a disease in itself but a sign of another problem, such as an infection, liver disease, or a disorder of the blood. Many people have no symptoms, and the enlargement is found during an exam or imaging done for another reason. Because an enlarged spleen is more fragile, protecting it from injury is an important concern.
Symptoms
An enlarged spleen often causes no symptoms. When symptoms occur, they may include:
- Fullness or discomfort in the upper left abdomen, sometimes spreading to the left shoulder
- Feeling full quickly after eating only a little, because the spleen presses on the stomach
- Fatigue, which may be related to anemia
- Frequent infections
- Easy bruising or bleeding
Symptoms of the underlying cause, such as fever with an infection or jaundice with liver disease, are often present as well. Sudden, severe pain in the upper left abdomen can signal a ruptured spleen and needs emergency care.
Causes
Many conditions can enlarge the spleen, including:
- Infections: Viral infections such as mononucleosis, as well as some bacterial and parasitic infections such as malaria.
- Liver disease: Cirrhosis and other liver conditions that raise pressure in nearby blood vessels.
- Blood disorders: Certain anemias, including sickle cell-related conditions, and disorders affecting blood cells.
- Cancers: Leukemias and lymphomas.
- Other causes: Inflammatory and metabolic conditions and, sometimes, congestion from blocked blood flow.
Finding the cause is the main goal of evaluation, since treatment is usually directed at the underlying condition.
Risk Factors
- Recent or current infections such as mononucleosis or malaria
- Liver disease, including cirrhosis
- Blood disorders and certain cancers
- Living in or traveling to areas where infections like malaria are common
- Conditions that cause chronic inflammation
Diagnosis
An enlarged spleen may be felt during an abdominal exam. To confirm it and find the cause, tests may include:
- Imaging: Ultrasound or CT scan to measure the spleen and look at nearby organs.
- Blood tests: A complete blood count and other tests to check blood cells, the liver, and for infections.
- Tests for the underlying cause: Such as tests for specific infections, liver function studies, or, in some cases, a bone marrow exam.
The pattern of results helps point to the condition responsible for the enlargement.
Treatment
Treatment is aimed mainly at the underlying cause rather than the spleen itself.
- Treating the cause: For example, antibiotics or antiviral support for infections, or managing liver disease or a blood disorder.
- Watchful waiting: When the spleen is enlarged from a temporary cause such as mononucleosis, it may return to normal as the illness resolves.
- Activity precautions: Avoiding contact sports and heavy activity while the spleen is enlarged, to reduce the risk of rupture.
- Spleen removal (splenectomy): Occasionally needed for severe symptoms or specific conditions. People without a spleen need certain vaccinations and prompt treatment of infections.
Prevention
Splenomegaly itself often cannot be prevented, but you can reduce some risks and complications:
- Take precautions against infections such as malaria when traveling
- Manage chronic conditions such as liver disease as advised
- Avoid contact sports and heavy lifting while the spleen is known to be enlarged
- Wear a seatbelt to protect the abdomen in vehicles
- If you have had your spleen removed, keep recommended vaccinations up to date
When to See a Doctor
See a doctor if you have ongoing fullness or pain in the upper left abdomen, feel full after small meals, or have symptoms such as unexplained fatigue, frequent infections, or easy bruising.
Seek emergency care immediately for sudden, severe pain in the upper left abdomen, especially after an injury or fall, as this may indicate a ruptured spleen, which can cause dangerous internal bleeding.
Frequently Asked Questions
Is an enlarged spleen serious?
It depends on the cause. Splenomegaly is usually a sign of another condition rather than a disease itself, and some causes are mild and temporary while others are serious. Because an enlarged spleen is fragile and can rupture, sudden severe upper-left abdominal pain is an emergency.
What are the most common causes of splenomegaly?
Frequent causes include infections such as mononucleosis or malaria, liver disease such as cirrhosis, blood disorders, and cancers like leukemia and lymphoma. Evaluation focuses on finding the underlying cause, since that guides treatment.
Why should I avoid contact sports with an enlarged spleen?
An enlarged spleen sits lower and is more exposed and fragile than normal, so a blow to the abdomen can rupture it and cause serious internal bleeding. Doctors usually advise avoiding contact sports and heavy activity until the spleen returns to normal size.
Can the spleen return to normal size?
Yes, when the cause is temporary, such as a viral infection like mononucleosis, the spleen often shrinks back to normal as the illness resolves. With chronic causes, treating the underlying condition is needed and the spleen may stay enlarged.
What happens if the spleen has to be removed?
People can live without a spleen, but they are more prone to certain serious infections. They need recommended vaccinations, sometimes preventive antibiotics, and prompt medical attention for fevers and infections.
References
- Mayo Clinic. Enlarged spleen (splenomegaly) — Symptoms and causes.
- MedlinePlus, U.S. National Library of Medicine. Enlarged spleen.
- Merck Manual Consumer Version. Enlarged Spleen.
- Centers for Disease Control and Prevention (CDC). Asplenia and vaccination.