Pediatric Splenomegaly

Updated: Jul 08, 2019
  • Author: Alexander Gozman, MD; Chief Editor: Vikramjit S Kanwar, MBBS, MBA, MRCP(UK), FAAP  more...
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Practice Essentials

Splenomegaly refers to splenic enlargement, as assessed by size or weight. [1] Splenomegaly in childhood is generally first suspected upon physical examination. One third of newborns and 10% of children may normally have a palpable spleen. The tip of the normal, palpable spleen is soft, smooth, nontender and less than 1-2 cm below the left costal margin. A pathologically enlarged spleen is often firm, may have an abnormal surface, and is frequently associated with signs and symptoms of the underlying disease. When any of these features are noted, or if the tip of the spleen is enlarged more than 1-2 cm below the costal margin, further evaluation should be considered. [2, 3] Because splenomegaly is usually the result of a systemic disease, the primary goal is treatment of the underlying process, although in some cases, splenectomy may be employed.

Signs and symptoms

These include the following:

  • Failure to thrive
  • Ill appearance
  • Pallor
  • Petechiae
  • Jaundice
  • Itching
  • Rashes
  • Eczematous rash
  • Icterus
  • Cherry red retinal spots
  • Cloudy corneas
  • Dyspnea
  • Fatigue
  • New murmur
  • Abdominal tenderness
  • Enlarged liver
  • Joint pain
  • Poor bone growth
  • Bone pain
  • Poor vision
  • Uveitis
  • Iritis
  • Loss of developmental milestones


Splenomegaly is usually the result of systemic disease rather than primary splenic disease. Therefore, diagnostic studies are not directed at the spleen itself. Instead, they are oriented at diagnosing disease states that result in splenomegaly. The most useful initial laboratory tests include the complete blood count (CBC) with differential, peripheral blood smears, and liver function tests. [4]

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).

Computed tomography (CT) scanning and magnetic resonance imaging (MRI) of the left upper quadrant can help in further clarifying abnormalities in splenic size and shape and in defining parenchymal pathology. [5, 6]


Because splenomegaly is usually the result of a systemic disease, the primary goal is treatment of the underlying process. In certain circumstances, splenectomy may be the therapy of choice for symptoms or complications caused by the enlarged organ. However, because of the risk of overwhelming sepsis in children who are asplenic, the risks and benefits must be carefully weighed when splenectomy is being considered. [7, 8]

Splenic trauma is the most common indication for splenectomy, although attempts at splenic preservation are important. Nonsurgical management for splenic trauma has success rates of 52-98%, with failure usually occurring in the first 96 hours. Splenic cysts, tumors, and vascular lesions may also require surgical removal.




The spleen is the largest lymphoid organ in the body. Using ultrasonographic measurements, Rosenberg et al proposed that normal splenic lengths should be no greater than the following [9] :

  • 6.0 cm at age 3 months
  • 6.5 cm at age 6 months
  • 7.0 cm at age 12 months
  • 8.0 cm at age 2 years
  • 9.0 at age 4 years
  • 9.5 cm at age 6 years
  • 10.0 cm at age 8 years
  • 11.0 cm at age 10 years
  • 11.5 cm at age 12 years
  • 12.0 cm at age 15 years or older (females);13.0 cm at age 15 years or older (males)

The spleen and the lymph nodes are the major components of the mononuclear-phagocyte system (MPS). They serve as filters that remove damaged cells, microorganisms, and particulate matter and deliver antigens to the immune system. The MPS, originally called the reticuloendothelial system, consists of fixed phagocytic cells in different organs. These phagocytes locally interact with lymphocytes and play an essential role in the recognition of antigens and their interaction with immunocompetent cells. [10]

The splenic tissue consists of red and white pulp lying in a capsule. Blood enters the spleen through the splenic artery, a branch of the celiac artery. It then travels into the smaller arterioles and approaches the white pulp. The white pulp, rich in T and B lymphocytes, receives plasma for antigen processing. Splenic macrophages efficiently ingest these antigens and deliver them to the immunocompetent cells of the spleen for antibody production and stimulation of T-lymphocyte immune responses. The remaining hemoconcentrated blood continues into the contiguous red pulp, the sinuses and cords of which are also lined with macrophages.

The red pulp forms most of the splenic tissue and consists of splenic cords, the circulation of which is designated as open because no well-defined endothelial lining is present. To exit the cords, blood must pass through 1-µm to 5-µm slits in this fenestrated basement membrane to reach the venous sinusoids. The circulation through the cords is slow and congested. This delay provides prolonged exposure of blood cells, bacteria, and particulate matter to the dense mononuclear-phagocyte elements in the red pulp.

After reaching the sinuses, blood from the red pulp empties into the splenic vein, which joins the superior mesenteric vein to form the hepatic portal vein. Because no valves are present in the splenic venous system, the pressure in the splenic vein reflects the pressure in the portal vein.


One of the primary functions of the spleen is the filtration of defective cells. Erythrocytes slowly pass through the hypoxic and acidotic environment of the splenic cords and then squeeze through narrow slits into the sinusoids. Although healthy erythrocytes readily accomplish this passage, aged and abnormal red cells, such as spherocytes and sickle cells, remain behind to be ingested by the macrophages lining the cords. [11] Fc receptors on splenic macrophages also bind to IgG antibody-coated erythrocytes or platelets, which are mainly cleared by the spleen.

The spleen is also critical for clearing circulating, particularly encapsulated, bacteria. The amorphous polysaccharide coat of encapsulated bacteria greatly impairs their clearance in the absence of antibody, and only the spleen's highly efficient phagocytic cords can effectively clear them. The splenic white pulp processes these intravenous antigens and produces antibody that, during subsequent exposures, allows for efficient clearance by the rest of the MPS.

The splenic cords are uniquely capable of removing erythrocytic inclusions, such as nuclear remnants (ie, Howell-Jolly bodies) or precipitated globin (ie, Heinz bodies), without destroying the cell. The spleen also serves as a reservoir for platelets and produces blood components (extramedullary hematopoiesis) if the bone marrow is unable to meet demands. [12]




United States

A 1-cm to 2-cm splenic tip is palpable in 30% of full-term neonates and in as many as 10% of healthy children. Approximately 3% of healthy college freshmen have palpable spleens. Initial and follow-up studies confirm that these college freshmen are not at high risk for subsequent serious disease. [13, 14, 2]


Malaria, schistosomiasis, and other infections in endemic areas are frequent causes of splenomegaly. [15]

In malaria-endemic areas, the prevalence of splenomegaly (ie, spleen rate) is a measure of malaria exposure. In hyperendemic areas (eg, Papua New Guinea), the spleen rate in children exceeds 50%. [16] Such hyperendemic areas have a prevalence of massive splenomegaly (hyperreactive malarial splenomegaly) of 1-2% in children. [17]


Splenic rupture may occur in acute splenomegaly associated with infectious mononucleosis. The incidence is 1:1000, and it usually occurs in the first 3 weeks of illness. [18]

Splenectomy is uncommonly performed in children with splenomegaly. Nevertheless, should it be clinically indicated, the overall risk of postsplenectomy sepsis is approximately 2%, with increased incidence and mortality in young children. [7, 8]

Hypersplenism is the occurrence of thrombocytopenia, and occasionally leukopenia and anemia, in the context of significant splenomegaly. [19] The cytopenias are usually mild but may contribute to overall morbidity. [20]


Specific causes of splenomegaly are most common in certain racial groups. Examples include splenic sequestration as a complication of sickle cell disease in patients of African or Mediterranean ancestry and noncirrhotic portal fibrosis in patients of Iranian, South Asian, or Japanese ancestry. [21]


The etiology of splenomegaly varies with age. For example, splenic sequestration in sickle cell disease occurs early in life, before the splenic involution that ultimately occurs in most patients with sickle cell disease.