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Harry S. Jacob

, MD, DHC, University of Minnesota Medical School

Last full review/revision Apr 2021| Content last modified Apr 2021
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Splenomegaly is abnormal enlargement of the spleen.

Splenomegaly is almost always secondary to other disorders. Causes of splenomegaly are myriad, as are the many possible ways of classifying them (see table Common Causes of Splenomegaly). In temperate climates, the most common causes are

In the tropics, the most common causes are

If splenomegaly is massive (spleen palpable 8 cm below the costal margin), the cause is usually

Splenomegaly can lead to cytopenias, a disorder called hypersplenism.

Evaluation of Splenomegaly


Most of the presenting symptoms result from the underlying disorder. However, splenomegaly itself may cause early satiety by encroachment of the enlarged spleen on the stomach. Fullness and left upper quadrant abdominal pain are also possible. Sudden, severe pain suggests splenic infarction. Recurrent infections, symptoms of anemia, or bleeding manifestations suggest cytopenia and possible hypersplenism. In patients who have had blunt abdominal trauma within the last several weeks, splenic enlargement may have resulted from splenic subcapsular hematoma and sudden severe pain and/or shock may indicate splenic rupture.

Physical examination

The sensitivity for detection of ultrasound-documented splenic enlargement is 60 to 70% for palpation and 60 to 80% for percussion. Up to 3% of normal, thin, people have a palpable spleen. Also, a palpable left upper quadrant mass may indicate a problem other than an enlarged spleen such as a hypernephroma.

Other helpful signs include a splenic friction rub and shoulder pain that suggest splenic infarction as well as epigastric or splenic bruits that may occur due to increased blood flow. Adenopathy may suggest a lymphoproliferative, infectious, or autoimmune disorder.


Common Causes of Splenomegaly



Chronic hemolytic anemia

Hemoglobinopathies, including the thalassemias, sickle cell hemoglobin variants (eg, hemoglobin S-C disease, sickle/beta thalassemia), and congenital Heinz body hemolytic anemias

Red blood cell enzymopathies (eg, pyruvate kinase deficiency)

Red blood cell shape abnormalities (eg, hereditary spherocytosis, hereditary elliptocytosis)


Certain malformations of the portal venous vasculature

External compression or thrombosis of portal or splenic veins

Infectious and inflammatory

Connective tissue disorders (eg, rheumatoid arthritis with Felty syndrome), systemic lupus erythematosus

Secondary amyloidosis

Myeloproliferative and lymphoproliferative

Leukemias, especially chronic lymphocytic, large granular lymphocytic, and chronic myelogenous leukemia

Lymphomas, especially hairy cell leukemia and splenic marginal zone lymphoma

Storage diseases


Splenic cysts, usually caused by resolution of previous intrasplenic hematoma

Adapted from Williams WJ, et al: Hematology. New York, McGraw-Hill Book Company, 1976.


If confirmation of splenomegaly is necessary because the examination is equivocal, ultrasonography is the test of choice because of its accuracy and low cost. CT and MRI may provide more detail of the organ’s consistency. MRI is especially useful in detecting portal or splenic vein thromboses. Nuclear scanning is accurate and can identify accessory splenic tissue often found after splenectomy due to "work hypertrophy" of overlooked splenules or fragments released from a fractured spleen at the time of surgery. Occasionally, multiple spleen remnants can be found throughout the abdomen, often embedded in the neighboring pancreas, a condition called splenosis.

Specific causes suggested clinically should be confirmed by appropriate testing. If no cause is suggested, the highest priority is exclusion of occult infection, because early treatment affects the outcome of infection more than it does most other causes of splenomegaly. Testing should be thorough in areas of high geographic prevalence of infection or if the patient appears to be ill. Complete blood count (CBC), blood cultures, and bone marrow examination and culture should be considered. If the patient is not ill, has no symptoms besides those due to splenomegaly, and has no risk factors for infection, the extent of testing is controversial but probably includes CBC, peripheral blood smear, liver tests, and abdominal CT. Flow cytometry and immunochemical assays such as light chain measurements of peripheral blood and/or bone marrow sections is indicated if lymphoma is suspected. Lymphoma in the splenic marginal zone, which is uncommon, is often associated with hepatitis C infection (and is important to detect because it can be successfully treated with viral eradication).

Specific peripheral blood findings may suggest underlying disorders (eg, small-cell lymphocytosis in chronic lymphocytic leukemia, large granular lymphocytosis in T-cell granular lymphocyte [TGL] hyperplasia or TGL leukemia, atypical lymphocytes in hairy cell leukemia, and leukocytosis and immature forms in other leukemias). Excessive basophils, eosinophils, or nucleated or teardrop RBCs suggest a myeloproliferative neoplasm. Cytopenias suggest hypersplenism. Spherocytosis suggests hypersplenism or hereditary spherocytosis. Target cells, sickle-shaped cells, or spherocytes can suggest a hemoglobinopathy.

Liver test results are diffusely abnormal in congestive splenomegaly with cirrhosis; an isolated elevation of serum alkaline phosphatase suggests hepatic infiltration, as in myeloproliferative and lymphoproliferative disorders, miliary tuberculosis, and chronic fungal diseases (eg, candidiasis, histoplasmosis).

Some other tests may be useful, even in asymptomatic patients. Serum protein electrophoresis identifying a monoclonal gammopathy or decreased immunoglobulins suggests lymphoproliferative disorders or amyloidosis; diffuse hypergammaglobulinemia suggests chronic infection (eg, malaria, visceral leishmaniasis, brucellosis, tuberculosis), cirrhosis with congestive splenomegaly, sarcoidosis, or connective tissue disorders (eg, systemic lupus erythematosus, Felty syndrome in patients with rheumatoid arthritis) . Flow cytometry can identify a small monoclonal lymphocyte population suggestive of lymphoma. Elevation of serum uric acid suggests a myeloproliferative or lymphoproliferative disorder. Elevation of leukocyte alkaline phosphatase (LAP) suggests a myeloproliferative neoplasm, whereas decreased levels suggest chronic myelocytic leukemia.

If testing reveals no abnormalities other than splenomegaly, the patient should be reevaluated at intervals of 6 to 12 months or when new symptoms develop.

Treatment of Splenomegaly

  • Treatment of underlying disorder

Treatment is directed at the underlying disorder. An enlarged spleen itself in an asymptomatic patient needs no treatment unless severe hypersplenism is present. Patients with palpable or very large spleens probably should avoid contact sports and weight-lifting to decrease the risk of splenic rupture.

Key Points

  • Splenomegaly is almost always secondary to other disorders.

  • When testing for etiology of splenomegaly and no cause is immediately apparent, infectious causes are important to exclude.

  • Asymptomatic patients with an enlarged spleen do not require treatment but should avoid contact sports and weight-lifting to decrease the risk of splenic rupture.

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