What is the initial workup for a patient presenting with splenomegaly (enlargement of the spleen)?

Initial Workup for Splenomegaly

The initial workup for a patient presenting with splenomegaly should include a complete blood count with differential, peripheral blood smear review, comprehensive metabolic panel, and abdominal imaging (preferably ultrasound) to confirm and characterize the enlargement.

Confirming Splenomegaly

• Physical examination should include careful percussion and palpation of the entire liver and spleen with measurement of the liver span at the mid-clavicular line 1
• Abdominal ultrasound is the recommended first-line imaging modality to confirm splenomegaly and assess for focal lesions 1, 2
• A spleen size of 11-13cm in length is considered mild splenomegaly, while >13cm is considered clinically significant 3

Essential Laboratory Testing

• Complete blood count with differential to evaluate for cytopenias or abnormal cell populations 1, 2
• Peripheral blood smear review to identify abnormal cells suggestive of hematologic malignancy 1, 3
• Comprehensive metabolic panel to assess liver function 1, 2
• Lactate dehydrogenase (LDH) levels to screen for hemolysis or malignancy 1

Additional First-Line Testing Based on Clinical Suspicion

• Infectious disease workup:

  • Viral studies for EBV, CMV, HIV, and hepatitis (especially if immunosuppressed or with risk factors) 1, 4
  • Consider testing for endemic infections based on travel history (malaria, schistosomiasis) 2

• Hematologic evaluation:

  • Flow cytometry of peripheral blood for immunophenotyping if lymphoproliferative disorder is suspected 1
  • Testing for JAK2, CALR, and MPL mutations if myeloproliferative neoplasm is suspected 1, 3

Imaging Considerations

• Abdominal ultrasound should evaluate:

  • Splenic size and echotexture 1
  • Presence of focal lesions 1
  • Liver size and appearance 1, 2
  • Evidence of portal hypertension 2

• Consider CT or MRI of the abdomen if:

  • Ultrasound findings are equivocal 1
  • Lymphadenopathy needs further characterization 1
  • Evaluation of potential splenic infarction is needed 5

Further Diagnostic Steps Based on Initial Findings

• Bone marrow aspiration and biopsy should be performed if:

  • Abnormal cells are found in peripheral blood 1, 3
  • Unexplained cytopenias are present 1, 3
  • Myeloproliferative or lymphoproliferative disorder is suspected 1, 3

• Consider lymph node biopsy if lymphadenopathy is present and lymphoma is suspected 1

Common Etiologies to Consider

• Hematologic disorders:

  • Lymphoproliferative disorders (lymphomas, leukemias) 1, 3
  • Myeloproliferative neoplasms (polycythemia vera, essential thrombocythemia, myelofibrosis) 1, 5
  • Hairy cell leukemia 1

• Infectious causes:

  • Viral infections (EBV, CMV, HIV, hepatitis) 2, 4
  • Bacterial infections (endocarditis, tuberculosis) 2
  • Parasitic infections (malaria, schistosomiasis) 2

• Other causes:

  • Portal hypertension from liver disease 2
  • Autoimmune disorders 1
  • Infiltrative diseases 3

Special Considerations

• Patients with massive splenomegaly (>15cm below costal margin) may require more urgent evaluation due to higher risk of complications 6
• Patients on immunosuppressive medications (like biologics) have increased risk of infectious causes of splenomegaly 4
• Consider splanchnic vein thrombosis in patients with myeloproliferative disorders and splenomegaly 6

Management Considerations

• Treatment should be directed at the underlying cause 3
• Patients with splenomegaly should avoid contact sports due to risk of splenic rupture 2
• For symptomatic splenomegaly without clear etiology, referral to hematology is recommended 3, 2