Splenomegaly in Adults

Background

• Splenomegaly most often occurs as a secondary manifestation of a primary disease process or condition and may present with symptoms related to impingement of the enlarged spleen on other organs or with symptoms related to underlying cause. An enlarged spleen may also present as an incidental finding on imaging.
• Splenomegaly is typically defined as an enlarged spleen weighing > 250 g and with width > 4-5 cm, diameter > 7 cm, and length > 11 cm in adults by ultrasound or maximal craniocaudal dimension of 13 cm by computed tomography (CT) and may be palpable on physical exam.
• Enlargement of the spleen occurs through one or more mechanisms.
  • Causes associated with increased splenic function (work hypertrophy) include:
    • conditions that increase sequestration of abnormal red blood cells from circulation, such as sickle cell disease, hereditary spherocytosis, beta thalassemia, and congenital nonspherocytic hemolytic anemia
    • conditions associated with immune hyperplasia including infections and conditions of chronic inflammation and abnormal immunoregulation, such as autoimmune hemolytic anemia, immune-mediated thrombocytopenia, collagen vascular diseases, Felty syndrome, and sarcoidosis
    • conditions associated with extramedullary hematopoiesis, such as primary and secondary myelofibrosis
  • Causes associated with infiltration include:
    • conditions involving malignant infiltration into the spleen due to hematologic malignancies (for example, lymphoma and leukemia) or solid tumor metastases, and rarely, angiosarcoma (primary splenic malignancy)
    • conditions involving benign mass infiltration into the spleen such as, hemangiomas, splenic hamartomas, and splenic cysts
    • conditions involving abnormal intracellular or extracellular deposition of substances such as, amyloidosis, Gaucher disease, and glycogen storage disease
  • Causes associated with passive congestion (reduced venous outflow from the spleen) including cirrhosis with portal hypertension, heart failure, and splenic/portal/hepatic vein thrombosis.
• Presence of massive splenomegaly (usually defined as clinically palpable > 8 cm below left costal margin) may help limit diagnosis.

Evaluation

• Diagnostic approach involves a combination of history and physical exam, laboratory testing, and imaging to determine the cause of splenomegaly and to direct treatment.
• Obtain a complete history and perform a physical exam, including spleen percussion and palpation to evaluate presence and extent of splenomegaly.
• Perform blood and urine tests to evaluate hematologic and biochemical indices and examine for presence of infection and immunologic and inflammatory disorders.
• Most patients will require abdominal imaging with ultrasound and/or CT scan to evaluate size and characteristics of the spleen, as well as to evaluate adjacent organs.
• The clinical presentation of the patient can often help guide the initial diagnostic testing to be performed.
  • Patients presenting with left upper quadrant (LUQ) pain or tenderness suggests subscapular hematoma or rupture of spleen due to trauma or as complication of acute infectious disease, acute and chronic leukemias, or rarely lymphoma and should be evaluated by imaging of the spleen.
  • Patients without LUQ pain but presenting with acute or subacute febrile illness suggests subacute bacterial endocarditis which can be confirmed by blood culture. If negative for subacute bacterial endocarditis, peripheral blood smear and chest x-ray may help pursue investigation for infections such as mononucleosis, cytomegalovirus, toxoplasmosis, tuberculosis, or viral illness, and Hodgkin lymphoma.
  • In patients presenting with symptoms of anemia (without LUQ or acute or subacute febrile illness), complete blood count and peripheral blood smear may help point towards further investigation for conditions such as autoimmune hemolytic anemia, acute lymphocytic leukemia, or acute monocytic leukemia.
  • In patients presenting with symptoms or signs of liver disease, liver function tests and imaging of spleen and liver to test for congestive splenomegaly from liver disease (such as portal hypertension) should be performed.
  • For patients presenting with other signs and symptoms of chronic illness such as ruddy complexion and weight loss, complete blood count and peripheral blood smear should be obtained.
• If cause of splenomegaly remains unknown after thorough history and physical and diagnostic testing:
  • Consider watchful waiting for patients who are young and in otherwise relatively good health and splenic biopsy in other patients.
  • Consider diagnostic splenectomy if biopsy is contraindicated or when diagnosis remains essential after non-diagnostic biopsy.

Management

• Management of splenomegaly usually involves treatment of the underlying condition.
• Additional therapies:
  • Splenic irradiation provided pain relief and improve cytopenias from hematological malignancies.
  • Therapeutic splenectomy
    • Partial or complete removal of the spleen is not curative for most underlying causes of splenomegaly. Exceptions include some benign hematologic diseases (such as immune thrombocytopenia) and in rare instances of isolated splenic lesions.
    • Surgical approaches include laparoscopic or hand-assisted laparoscopic techniques (especially for spleen size < 2,000 g) and laparotomic (open) splenectomy (especially for spleen > 2,000 g).
    • Generally indicated in the presence of splenic rupture, abscess/cysts, neoplasms, and aneurysm of splenic artery.
    • Splenectomy may also be performed to relieve symptoms of severe/massive splenomegaly and cytopenias, such as anemia severe enough to require blood transfusion, and hypersplenism. Specific indications for splenectomy depends on the clinical context.
• Additional considerations include:
  • management of splenic cysts
  • management of patients with primary splenic lymphoma