Pediatric Splenomegaly Workup

Updated: Mar 29, 2022
  • Author: Trisha Simone Natanya Tavares, MD; Chief Editor: Vikramjit S Kanwar, MBBS, MBA, MRCP(UK)  more...
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Approach Considerations

Splenomegaly is usually the result of a systemic disorder rather than primary splenic disease. Therefore, diagnostic studies are not directed solely towards the spleen. Instead, the goal of testing should be to evaluate any abnormal findings detected during the history or physical examination. 

The most useful initial laboratory test is the complete blood count (CBC) with manual differential and peripheral blood smear. This test should be performed on all patients with an enlarged spleen.

Assessment of transaminase levels and other examinations of hepatobiliary function may be indicated. Additional diagnostic studies will depend on the patient presentation and should be tailored to each individual.

Imaging is not required for all children who are being evaluated for splenomegaly. If imaging is performed, ultrasonography is recommended; this modality can be used to measure splenic dimensions and show splenic architecture. Ultrasonography will also rule out the presence of space-occupying lesions and will provide information about other intra-abdominal organs. 

Computed tomography (CT) scanning and magnetic resonance imaging (MRI) of the left upper quadrant can help in further evaluating splenic parenchymal architecture, and can be used in defining splenic size and shape. [7, 8] These imaging modalities are, however, rarely indicated. Ultrasonography alone is the most appropriate means of imaging the spleen in pediatric patients, since it is noninvasive and does not employ ionizing radiation; moreover, it lacks radiographic magnification, and patients are not subject to the osmotic side effects of iodinated contrast. In addition to being safe, ultrasonography displays real-time images and is easily repeated, with no anesthesia required. [1]

CT scanning or MRI should be used only if there is a clear need for additional imaging detail that cannot be provided by ultrasonography. Emitting gamma radiation, technetium-99m (99mTc) sulfur colloid can be used to examine the reticuloendothelial system via scintillation scanning; moreover, it is the only test that provides functional information about the spleen. It is not indicated in routine evaluation of splenomegaly. [9]


Laboratory Studies

The most useful initial laboratory tests include a complete blood count (CBC) with differential, peripheral blood smears, and liver function tests. [52]

The CBC may be revealing, as follows:

  • Pancytopenia may be present because of bone marrow infiltration and hypersplenism.

  • The WBC count may reveal atypical lymphocytes (eg, neutropenia, or neutrophilia (eg, due to infection or leukemia).

  • Hemoglobin concentrations, RBC smears, and reticulocyte counts may reveal anemia, abnormal erythrocyte morphology, reticulocytosis (eg, due to hemolysis), or malarial parasites.

  • The platelet count may indicate thrombocytopenia due to decreased production (eg, due to bone marrow infiltration), increased destruction (eg, due to immunologic causes, drug reactions, or viral infections), or sequestration or hypersplenism.

Hepatobiliary function tests may identify abnormalities, as follows: 

Obtain an antinuclear antibody titer to screen for systemic lupus erythematosus if there are signs or symptoms that indicate a rheumatologic etiology for splenomegaly.

Measure immunoglobulin levels, neutrophil function, and T-cell subclasses (eg, due to immunodeficiency).

Viral testing may be appropriate for some patients. Consider testing for EBV, CMV, Toxoplasma gondii, parvovirus, and HIV, as indicated. Perform appropriate testing to detect malaria in high-risk populations.

Cultures may reveal bacterial, fungal, or other infections.

Examine the bone marrow to screen for leukemia, lymphoma, storage diseases, and disseminated fungal or mycobacteria infections, if indicated based on other findings on history and physical examination.


Imaging Studies

Ultrasonography can confirm the presence of the enlarged spleen or space-occupying lesions (eg, cyst, abscess), provide accurate dimensions, and help in distinguishing between splenic enlargement and other causes of a left subchondral mass (eg, kidney). Confirming or excluding splenomegaly in patients with obesity, in whom palpation can be very challenging, is useful. Often, a single craniocaudal measurement is used to report spleen size; awareness of the normal values for age is important. [58] Collateral blood vessels develop secondary to portal hypertension, and reversal of portal vein blood flow direction may be visualized with Doppler ultrasonography.

CT scanning and MRI of the left upper quadrant can help in further clarifying abnormalities in size and shape and in defining parenchymal pathology. The "splenic index" is the product of the length, width, and thickness of the spleen and has limited value. [7, 8]

Radioisotopic scanning with a 99mTc sulfur colloid (spleen scan) can provide functional information about the spleen that other radiologic studies do not provide. [30]


Histologic Findings

Biopsy of the spleen may be performed. The results are of limited value in common diagnoses, and the procedure is associated with a notable risk, particularly bleeding.

The diagnosis is occasionally recognized after splenectomy.

Examples of disease that might be examined with biopsy include infiltrative diseases, such as Gaucher disease, Niemann-Pick disease, amyloidosis, Tangier disease, and glycogen-storage diseases. Other diseases that may be diagnosed with splenic tissue include Langerhans cell histiocytosis, sarcoidosis, systemic lupus erythematosus, and Hodgkin disease. In Hodgkin disease, biopsy samples were often obtained in the past with staging laparotomy, but this is no longer performed because of improved imaging and systemic therapy.