Splenomegaly

Background

• The spleen normally weighs 150-200g in adults and is not palpable on exam
• A palpable spleen tip below the left costal margin generally indicates at least 1.5-2× enlargement — by the time a spleen is palpable, it is significantly enlarged
• Massive splenomegaly (spleen extends beyond the umbilicus or >20 cm on imaging) has a narrower differential: chronic myeloproliferative disorders (especially CML), myelofibrosis, hairy cell leukemia, malaria, kala-azar (visceral leishmaniasis), Gaucher disease
• Hypersplenism = splenomegaly + cytopenias (from splenic sequestration and destruction of blood cells) — may see anemia, thrombocytopenia, and/or leukopenia

Clinical Features

Symptoms

• Often asymptomatic — discovered incidentally
• Left upper quadrant pain or fullness, early satiety (mass effect on stomach)
• Left shoulder pain (Kehr sign — referred diaphragmatic irritation from splenic pathology, classically splenic rupture or infarct)
• Symptoms of the underlying disease (fever, weight loss, night sweats, fatigue, bleeding, bruising)

Physical Exam

• Palpate from the right lower quadrant toward the left costal margin with the patient supine or in right lateral decubitus position
• A palpable spleen moves with respiration, has a medial notch, and cannot be balloted (distinguishes from left kidney)
• Percussion: Castell's sign (dullness to percussion in the lowest left intercostal space in full inspiration) — sensitivity ~60-80% for splenomegaly
• Assess for associated findings: lymphadenopathy, hepatomegaly, jaundice, petechiae/purpura, stigmata of liver disease

ED Complications of Splenomegaly

• Splenic rupture: Both traumatic and atraumatic (especially EBV/mononucleosis, hematologic malignancy, malaria); presents with LUQ pain, peritoneal signs, and hemodynamic instability — surgical emergency
• Splenic infarction: Sudden LUQ pain, often pleuritic; associated with embolic sources (atrial fibrillation, endocarditis), myeloproliferative disorders, sickle cell disease, and hypercoagulable states
• Splenic abscess: Fever + LUQ pain + splenomegaly; associated with endocarditis, IV drug use, immunosuppression; diagnosed on CT
• Splenic sequestration crisis: Acute painful enlargement with acute anemia in sickle cell disease — more common in children; can be rapidly fatal

Differential Diagnosis

Infectious

• Viral: EBV (mononucleosis — most common infectious cause in young adults), CMV, HIV, viral hepatitis
• Bacterial: Endocarditis, tuberculosis, brucellosis, typhoid, splenic abscess
• Parasitic: Malaria (massive splenomegaly in endemic areas), kala-azar (visceral leishmaniasis), schistosomiasis
• Fungal: Disseminated histoplasmosis, disseminated candidiasis (immunocompromised)

Hematologic Malignancy

• Leukemia: CML (often massive), CLL, ALL, AML, hairy cell leukemia
• Lymphoma: Hodgkin and non-Hodgkin (especially splenic marginal zone lymphoma)
• Myeloproliferative neoplasms: Polycythemia vera, essential thrombocythemia, primary myelofibrosis (often massive)
• Myelodysplastic syndromes

Congestive (Portal Hypertension)

• Cirrhosis — most common cause of splenomegaly in adults in developed countries
• Portal vein thrombosis
• Splenic vein thrombosis
• Congestive heart failure (severe right-sided)
• Budd-Chiari syndrome

Hemolytic Anemias

• Sickle cell disease (before autosplenectomy in adults; splenic sequestration in children)
• Hereditary spherocytosis
• Thalassemia major
• Autoimmune hemolytic anemia
• G6PD deficiency (during hemolytic crisis)

Autoimmune/Inflammatory

• Systemic lupus erythematosus
• Adult-onset Still's disease / Systemic JIA
• Rheumatoid arthritis (Felty syndrome = RA + splenomegaly + neutropenia)
• Sarcoidosis
• Macrophage activation syndrome / Hemophagocytic lymphohistiocytosis

Infiltrative/Storage Diseases

• Gaucher disease (most common lysosomal storage disease; can cause massive splenomegaly)
• Niemann-Pick disease
• Amyloidosis
• Glycogen storage diseases

Other

• Splenic cysts (congenital, post-traumatic, hydatid)
• Splenic hemangioma or other benign tumors
• Metastatic disease to spleen (rare)

Massive Splenomegaly (Short Differential)

Spleen palpable >8 cm below costal margin or >20 cm on imaging:

• CML
• Myelofibrosis
• Hairy cell leukemia
• Malaria (chronic/hyperreactive)
• Kala-azar (visceral leishmaniasis)
• Gaucher disease
• Polycythemia vera
• Splenic marginal zone lymphoma

Evaluation

Workup

• CBC with differential and peripheral blood smear — cytopenias suggest hypersplenism; blasts or abnormal cells suggest malignancy; spherocytes or schistocytes suggest hemolysis; atypical lymphocytes suggest EBV/CMV
• Reticulocyte count — elevated in hemolytic anemias
• LFTs, albumin, INR — assess for liver disease/cirrhosis
• LDH, haptoglobin, indirect bilirubin — hemolysis panel
• CRP, ESR — inflammatory/infectious evaluation
• Ferritin — markedly elevated in MAS/HLH, AOSD/sJIA, malignancy
• Peripheral blood smear — do not skip this — may show blasts (leukemia), teardrop cells (myelofibrosis), target cells (thalassemia/liver disease), hairy cells, or parasites (malaria)
• Blood cultures — if febrile
• Monospot or EBV VCA IgM — in young adults with pharyngitis, lymphadenopathy, and splenomegaly
• HIV — screen in all unexplained splenomegaly
• Hepatitis B/C serologies — if liver disease suspected
• Imaging:
  • Ultrasound — first-line to confirm and measure spleen size; also assesses liver, portal vein, and hepatic vasculature
  • CT abdomen with contrast — if concern for splenic infarction, abscess, mass, or if evaluating for lymphadenopathy/malignancy
• Lactate, coagulation studies — if concern for sepsis, splenic rupture, or DIC
• Type and screen — if concern for splenic rupture or significant anemia

Management

• Treat the underlying cause
• Splenic rupture: Hemodynamic resuscitation, emergent surgical consultation, massive transfusion protocol if indicated (see Splenic injury)
• Splenic infarction: Supportive care, analgesia, anticoagulation if embolic source identified; surgical consultation if concern for abscess formation or rupture
• Splenic abscess: IV antibiotics + interventional radiology or surgical drainage
• Splenic sequestration crisis (sickle cell): Aggressive IV fluids, transfusion (target Hgb rise of 1-2 g/dL — avoid over-transfusion which can cause auto-transfusion from the spleen and hyperviscosity), emergent hematology consultation
• Activity restriction: Counsel patients with newly diagnosed splenomegaly (especially EBV/mononucleosis) to avoid contact sports and heavy lifting until splenomegaly has resolved — risk of splenic rupture

Disposition

• Admit: Splenic rupture, splenic infarction with hemodynamic instability, splenic abscess, splenic sequestration crisis, new diagnosis of hematologic malignancy, unexplained massive splenomegaly with cytopenias, suspected MAS/HLH
• Discharge with urgent follow-up (24-72h): Hemodynamically stable patients with incidentally discovered mild-moderate splenomegaly and non-critical initial labs; ensure follow-up with hematology, hepatology, or primary care with pending workup communicated
• Return precautions: LUQ pain, lightheadedness/syncope, worsening fatigue, fevers, bleeding/bruising; avoid contact sports

See Also

• Splenic injury
• Mononucleosis
• Cirrhosis
• Leukemia
• Lymphoma
• Sickle cell disease
• Macrophage activation syndrome
• Adult-onset Still's disease
• Fever of unknown origin
• Ferritin