EM@3AM: Splenomegaly

Author: Elizabeth Adams, MD (EM Resident Physician, UTSW, Dallas, TX) // Reviewed by: Sophia Görgens, MD (EM Resident Physician, Zucker-Northwell NS/LIJ, NY), Cassandra Mackey, MD (Assistant Professor of Emergency Medicine, UMass Chan Medical School), and Alex Koyfman, MD (@EMHighAK) 

Welcome to EM@3AM, an emDOCs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

Vitals: HR 108, BP 118/78, RR 20, Temp 100.8F, SpO2 100% on room air.  On exam, she has a scaphoid abdomen with a left-sided palpable mass extending 8cm past her rib cage, consistent with splenomegaly. She is fatigued-appearing and tachycardic, but the rest of her physical exam is normal.   

What is the approach to the patient with splenomegaly? 

Diagnosis:  Splenomegaly, unclear etiology 

Background: 

• The spleen is responsible for removal of damaged red blood cells and plays an important role in the immune system by filtering pathogens out of the blood and initiating immune reactions by bringing those foreign antigens into contact with specialized cells of the immune system^1,2
• The spleen plays an important role in hematopoiesis (production of blood cell lineages) during fetal development but can become a site of extramedullary hematopoiesis in pathologic states.^3,4

Pathophysiology:  

• A pathologically enlarged spleen, identified either on exam or imaging, warrants evaluation to determine the underlying etiology
• The definition of splenomegaly varies, but most agree that a spleen larger than 10-13cm in any direction is enlarged, although slightly larger spleens up to 14cm can be physiologic in tall individuals^2,3,4
• A spleen measuring larger than 20cm is considered massive splenomegaly³
• The three most common causes of splenomegaly are liver disease (33%), hematologic malignancy (27%), and infection (23%).⁴

History and Exam: 

• Important historical elements to obtain: 
  • Patient age – for example, a child presenting with splenomegaly may be a new diagnosis of sickle cell disease, while an older individual may be a new cancer diagnosis
  • Duration of symptoms 
  • Presence of symptoms that suggest anemia or thrombocytopenia, including easy bruising/bleeding, shortness of breath, fatigue
  • Presence of symptoms that may suggest malignancy or infection, including weight loss, night sweats, lymphadenopathy or fever
  • Past medical history of cardiac disease, liver disease, sickle cell disease, autoimmune disease or cancer
  • Recent trauma
•  Physical exam technique for identifying splenomegaly:
  • Have the patient lie flat or in the right lateral decubitus position with arms at their sides, then slowly palpate the left side starting at the rib cage and moving caudally all the way down to the pelvis to locate the bottom edge of the spleen, which can vary greatly with respiration.⁵ 
  • The use of bedside ultrasound in addition to physical exam significantly increases the sensitivity of identifying splenomegaly.⁶ 
• The presence of splenomegaly may be missed on the exam for multiple reasons: 
  • The spleen is enlarged but still too small to palpate successfully – some articles suggest that the spleen must be enlarged by at least 40% to be palpable below the rib cage⁷
  • The spleen is significantly enlarged, and the lower edge of the spleen is in the pelvis 
  • The patient’s body habitus may limit the exam

Differential: 

• The differential diagnosis for splenomegaly is broad and can be broken into 3 main categories: 1) congestion due to increased vascular pressure 2) increased size due to hemolysis of blood 3) infiltration by other cells/material.⁵
• Differential for splenomegaly related to increased vascular pressure:
  • Cirrhosis
  • Congestive heart failure
  • Splenic vein, portal vein, or splanchnic vein thrombosis
  • Vaso-occlusive crisis secondary to sickle cell disease leading to splenic sequestration
• Differential for splenomegaly related to hemolysis of blood:
  • Autoimmune hemolytic anemia 
    • Seen in patients with other autoimmune disorders including SLE, rheumatoid arthritis, Sjogren’s, Hashimoto’s thyroiditis, Felty syndrome
  • Immune thrombocytopenia
  • Hemolytic uremic syndrome
  • Thrombotic thrombocytopenic purpura
• Differential for splenomegaly related to infiltration by cells/material
  • Infiltration by cancerous cells: primary malignancy (splenic marginal zone lymphoma), hematologic cancers (ALL, CLL, CML, polycythemia vera) or metastasis (most commonly melanoma, breast and lung cancer)⁵
  • Infiltration by blood/lymph cells in response to infection: EBV, CMV, HIV, mycobacteria, brucellosis, babesiosis, bartonella, histoplasmosis, leptospirosis, malaria, visceral leishmaniasis⁵
  • Amyloidosis
  • Sarcoidosis
  • Gaucher disease
• Other conditions
  • Splenic hemangioma
  • Splenic hemangiosarcoma
  • Traumatic injury resulting in splenic hematoma

ED Evaluation: 

• Given the broad differential for splenomegaly, the evaluation in the emergency department typically includes obtaining the initial workup and determining if the patient needs to be admitted for additional workup versus discharged with outpatient follow up.
• Obtain lab-work including:
  • Complete blood count with differential and smear
  • Liver function tests
  • Serologic testing for possible infections (see above)
  • Hemolysis labs including lactate dehydrogenase (LDH), unconjugated bilirubin (indirect bilirubin), haptoglobin and reticulocyte count

Management: 

• An ill-appearing individual with splenomegaly needs to be admitted for an expedited workup of underlying etiology and consideration of splenic rupture.
• A well-appearing individual with atraumatic splenomegaly can be reasonably discharged with outpatient primary care and hematology follow up.
• Management varies greatly depending on the etiology of the splenomegaly. For example, admission and resuscitation for splenic sequestration due to sickle cell vaso-occlusive crisis versus discharge with supportive care and precautions in the patient found to have infectious mononucleosis with mild splenomegaly.

Complications: 

• Splenic rupture is a feared and life-threatening complication of splenomegaly; therefore, it is generally recommended to avoid contact sports to reduce this risk
• Cytopenia and immune dysfunction related to sequestration of cells within the spleen can lead to bleeding and infections⁴

Take-home Points: 

• Bedside ultrasound in combination with physical exam is more sensitive for identifying splenomegaly compared to physical exam alone.
• The differential diagnosis for splenomegaly is broad but can be simplified into 3 main groups: 1) increased vascular pressure; 2) hemolysis of blood; 3) infiltration by cells/material.
• Management of splenomegaly in the emergency department is centered on initial testing to identify possible underlying causes and appropriate determination of the need for expedited inpatient workup versus outpatient workup and possible referral to hematology.
• Undiagnosed splenomegaly can lead to a delay in diagnosis of the underlying condition or potential splenic rupture, particularly in those involved in contact sports.

Further Reading:

#FOAMed

EMDocs on splenic infarction: http://www.emdocs.net/splenic-infarction-in-mononucleosis-pearls-and-pitfalls/ 

Ultrasonography technique for measuring the spleen: https://ultrasoundpaedia.com/spleen-normal/ 

References: 

1. Cesta MF. Normal structure, function, and histology of the spleen. Toxicol Pathol. 2006;34(5):455-65. doi: 10.1080/01926230600867743. PMID: 17067939.
2. Gaillard, F., Niknejad, M. Splenomegaly. Radiopaedia.org. https://doi.org/10.53347/rID-6003
3. Chapman J, Goyal A, Azevedo AM. Splenomegaly. [Updated 2021 Aug 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan.
4. Sjoberg BP, Menias CO, Lubner MG, Mellnick VM, Pickhardt PJ. Splenomegaly: A Combined Clinical and Radiologic Approach to the Differential Diagnosis. Gastroenterol Clin North Am. 2018 Sep;47(3):643-666. doi: 10.1016/j.gtc.2018.04.009. Epub 2018 Jul 7. PMID: 30115442.
5. Bona R. Evaluation of splenomegaly and other splenic disorders in adults. UpToDate. 2022 Jul 25. 
6. Olson AP, Trappey B, Wagner M, Newman M, Nixon LJ, Schnobrich D. Point-of-care ultrasonography improves the diagnosis of splenomegaly in hospitalized patients. Crit Ultrasound J. 2015 Dec;7(1):13. doi: 10.1186/s13089-015-0030-8. Epub 2015 Sep 17. PMID: 26383010; PMCID: PMC4574040.
7. Yang JC, Rickman LS, Bosser SK. The clinical diagnosis of splenomegaly. West J Med. 1991 Jul;155(1):47-52. PMID: 1877230; PMCID: PMC1002911.
8. Hindi C, Pastores G, Brady R et al. Gaucher Disease. NORD (National Organization for Rare Disorders), 27 Mar. 2020, rarediseases.org/rare-diseases/gaucher-disease/.