From the Guidelines
Splenomegaly is primarily caused by conditions such as infections, hematologic disorders, portal hypertension, inflammatory conditions, storage diseases, and splenic cysts or tumors, which lead to congestion, infiltration, or hyperplasia of the spleen. These conditions can cause the spleen to enlarge as it responds by increasing its filtering and immune functions. According to 1, splenic abscess, a complication of infective endocarditis, is a rare cause of splenomegaly, and it develops through bacteremic seeding of a bland infarction or direct seeding of the spleen by an infected embolus.
Common Causes of Splenomegaly
- Infections (such as mononucleosis, malaria, tuberculosis, and bacterial endocarditis)
- Hematologic disorders (like hemolytic anemias, leukemias, lymphomas, and myeloproliferative disorders)
- Portal hypertension from liver disease
- Inflammatory conditions (such as sarcoidosis and rheumatoid arthritis)
- Storage diseases (like Gaucher's disease)
- Splenic cysts or tumors
As noted in 1, treatment of splenomegaly often focuses on addressing the underlying cause, and in cases of symptomatic splenomegaly, hydroxyurea is considered the first-line treatment of choice. The management of splenomegaly should prioritize treating the underlying condition, and splenectomy may be considered in severe cases where the spleen becomes extremely enlarged or causes complications like hypersplenism. Symptoms of splenomegaly may include left upper quadrant pain, early satiety, and sometimes a palpable mass below the left costal margin.
Diagnosis and Treatment
- Abdominal CT and MRI are the best tests for diagnosing splenic abscess, with sensitivities and specificities ranging from 90% to 95% 1
- Hydroxyurea is the first-line treatment of choice in PMF-associated splenomegaly 1
- Splenectomy is a viable treatment option for drug-refractory splenomegaly, but it is generally avoided when possible due to the spleen's important immune functions.
From the Research
Causes of Splenomegaly
The causes of splenomegaly can be diverse and are often associated with systemic conditions. Some of the common causes include:
- Liver disease, which is one of the most common causes of splenomegaly in the United States 2
- Malignancy, including lymphoma, which can be primary or secondary 2, 3
- Infection, such as malaria and schistosomiasis, which are common in tropical regions 2
- Hematologic diseases, such as lymphoma and other blood disorders 2, 4
- Hepatic diseases, including liver cirrhosis 5, 4
Systemic Conditions
Splenomegaly can also be associated with other systemic conditions, including:
- Infectious diseases, such as infectious mononucleosis 2
- Genetic disorders, such as Gaucher disease, although this is rare 4
- Autoimmune disorders, which can cause inflammation and enlargement of the spleen
Diagnostic Challenges
In some cases, the cause of splenomegaly may not be immediately apparent, and extensive diagnostic work-up may be necessary to determine the underlying cause 6, 4. This can include laboratory tests, imaging studies, and splenic biopsy. In some cases, the cause of splenomegaly may remain unknown, even after extensive evaluation 4.