Splenomegaly

Overview Splenomegaly generally denotes a palpably enlarged spleen. Splenomegaly can be found in 3% of the normal population. Causes of an enlarged spleen are multiple (hepatic, haemotological, infection or inflammation).

Definition
Hypersplenomegaly: abnormal enlargement of the spleen
Hypersplenism: defined as one or more blood cytopenias in the setting of splenomegaly.
Pancytopaenia: reduction in the number of RBCs, WBCs, and platelets in the peripheral blood below the lower limits of the age-adjusted normal range for healthy people. It is therefore the combination of anaemia, leukopenia, and thrombocytopenia.
Anatomy of the spleen

  • Location: Left hypochondrium
  • Rule of odds (1,3,5,7,9-11):
    • 1 inch thick
    • 3 inches broad
    • 5 inches long
    • 7 ounces weight
    • Underlies 9-11 ribs
  • Position: obliquely along long axis of 10th rib; directed downward, forward and laterally
  • Arterial supply: Splenic artery from celiac trunk
  • Venous drainage: Splenic vein → Portal vein
  • Lymphatic drainage: Celiac (Para-aortic) nodes
  • Nerve supply: Sympathetic from celiac plexus

Histology of the spleen

  • Red pulp: sinuses lined by endothelial macrophages and cords (spaces)
  • White pulp: structure similar to lymphoid follicles

Physiology of the spleen

  • Red pulp
  • White pulp
  • Removal of antibody-coated bacteria and antibody coated blood cells from circulation
  • Extramedullary haematopoesis
Watch Video Spleen anatomy and physiology
MAJOR CAUSES OF SPLENOMEGALY
Aetiology Conditions
Congestion Cirrhosis, Heart Failure, Thrombosis of portal/hepatic/splenic vein
Malignancy Lymphoma, Leukaemia, Myeloproliferative disorders, Primary or secondary tumour
Infection Viral (hepatitis, infectious mononucleosis, cytomegalovirus), bacterial (Salmonella, TB), parasitic (malaria, toxoplasmosis, schistosomiasis), infective endocarditis
Inflammation Sarcoids, SLE, Rheumatoid arthritis (Felty syndrome)
Infiltrative, nonmalignant Gacuher's disease, Niemann-pick disease, Amyloid, Langerhan cell histiocytosis
Haematologic (hypersplenic) states Haemolytic anaemias, Sick cell disease (children)
COMMON CAUSE OF SPLENOMEGALY
Adults Children
Liver disease Infection
Haematologic malignancy Sickle cell anaemia
Infection Thalassaemia
Congestion or inflammation
Primary splenic disease (splenic vein thrombosis)

Classification of Splenomegaly

  • Mild - just palpable
  • Moderate - below left costal margin and umbilicus
  • Massive (>8cm) - beyond umbilicus and goes up to pelvic brim
    • Myeloproliferative disorder
    • Chronic malaria
    • Storage disorders
    • Thalassaemia major
    • Sarcoidosis
    • Gaucher disease

Approach in Children

  • History
    • Fever
    • Race
    • Recent infection
    • Recent travel
    • Constitutional signs - systemic illness
    • Signs and symptoms of splenomegaly - Satiety, abdominal discomfort, dragging sensation, abdominal pain, shoulder tip pain
Remember Fever, pharngitis and malaise suggest viral aetiology
  • Examination - Perform GIT examintion
    • Lymphadenopathy - infection or malignancy
    • Jaudine - haemolytic anaemia or liver disease
    • Hepatomegaly  - Liver disease, myeloproliferative disorder
    • Spider angiomata - Liver disease
    • Rashes and or joint swelling - Systemic autoimmune disease
    • Petechiae and ecchymoses - thrombocytopaenia , malignant haemotolgic disease
Side note Proper examination of the spleen requires relaxation of both the abdominal musculature (arms at the side of abdomen) of the patient and the examiner hands (beware of tender spleen)
DIFFERENCE BETWEEN ENLARGED SPLEEN AND KIDNEY EXAMINATION
Enlarged Spleen Kidney
Sharpe edge Round edge
Crosses midline Does not cross midline
Moves with respiration Does not move with respiration
Cannet get above it Can get above it

Approach in Adults

  • History
    • Recent trauma
    • Race
    • Fever
    • Recent infection
    • Recent travel
    • Constitutional signs - systemic illness including malignancy and autoimmune disease
    • Pruritis - Myeloproliferative disorder
    • Alcohol or hepatitis - portal hypertension secondary to liver disease
    • Symptoms of splenomegaly - Satiety, abdominal discomfort, dragging sensation, abdominal pain, shoulder tip pain
Remember symptoms of splenomegaly include early satiety, abdominal discomfort and pain, irritation of diaphragm may cause shoulder tip pain
Remember Fever, pharngitis and malaise suggest viral aetiology
  • Examination - Perform GIT examination
    • Murmur- infective endocarditis, amyloidosis, rheumatic fever
    • Lymphadenopathy - infection or malignancy
    • Jaundice - haemolytic anaemia or liver disease
    • Hepatomegaly  - Liver disease, myeloproliferative disorder
    • Spider angiomata - Liver disease
    • Rashes and or joint swelling - Systemic autoimmune disease
    • Petechiae and ecchymoses - thrombocytopaenia , malignant haemotologic disease
Spider angiomata or spider naevus are common on the face and upper chest. They are given that name because they have a central red papule with feeding capillary legs. Occur in presence of extra oestrogen (pregnancy or liver disease)

Laboratory Investigations

Remember FBC and peripheral blood smear are very important in determining cause of the enlarged spleen!
  • Full blood count
    • Neutropaenia
    • Anaemia
    • Thrombocytopaenia
    • Neutrophilia - infection
  • Blood smear
    • Sepsis or malaria - Invading organisms maybe identified
    • Mycoplasma pnenomiae - Red blood cell agglutination due to presence of cold agglutinins
    • Infectious mononucleosis - Red blood cell agglutination due to presence of cold agglutinins and atypical lymphcytes
    • Bone marrow malignancy - band forms and nucleated red cells, tear drop red blood cells
    • Myelofibrosis - nucleated red cells, tear drop red blood cells
    • Polycythaemia rubra vera
    • Sickle cell anaemia - multple sickle cells
    • Beta thalassaemia trait - hypochromic and microcytic red blood cells
    • Beta thalassaemia intermedia - hypochromic, microcytic red blood cells. Red cell fragements, red cells with bizzare shapes as well
    • Systemic Lupus erythematosus - LE cells (viable neutrophil has ingested nuclear material)
    • Herediatary spherocytosis or autoimmune haemolytic anaemia - spherocytes
Remember Myelofibrosis blood smear findings include nucleated RBC, tear drop RBC (dacrocytes)
Side note Dacro comes from Greek word dakryo meaning tear or lacrimal
  • LFT
  • Coagulation profile
  • Amylase/Lipase
  • AMA, Anti CCP, RA factor
  • Bone marrow analysis
    • Bone marrow aspiration
    • Bone marrow biopsy

Imaging Investigations

  • MRI
  • CT
  • Ultrasound

Special investigation

  • Hemoglobin electrophoresis (↑HbF in B-thalssemia)
  • Coomb’s test (+ve in autoimmune hemolysis and -ve in hereditary spherocytosis)
  • Red cell enzyme testing (G6PD deficiency)
  • Osmotic fragility testing (+ve in Hereditary spherocytosis)
  • Flow cytometry for lymphoproliferative profile (CLL, Hairy cell leukemia, lymphomas)
  • Erythropoietin level (↓ in Polycythemia vera)
  • Coagulation test (Chronic liver disease, DIC in AML, SLE)
  • Serum lipase and amylase (Pancreatitis)
  • Serum LDH (NHL, AML)
  • Serum iron (↑ in Hemochromatosis, Thalassemia)
  • Paul-Bunnell test (Infectious Mononucleosis)
  • Congo red test (Amyloidosis)
  • Serum ACE (Sarcoidosis)
  • Napier’s Aldehyde test (Chronic Kala-azar)
  • Anti-nuclear antibodies (SLE)
  • Rheumatoid factor (RA, Felty’s syndrome)
  • HBsAg (Hepatitis)
  • Rose-Waaler test (Felty’s syndrome)
  • Glucocerbrosidase activity (Gaucher’s disease)
  • Sphingomyelinase (Niemann-Pick disease)
  • Mantoux skin test (TB)
  • Kveim skin test (Sarcoidosis)

Management

  • Splenectomy

Splenectomy is surgery to remove the entire spleen

  • Problems after splenectomy:
    • Immediate: Increased platelet count may lead to thromboembolic phenomenon
    • Long-term: Increased risk of infection with capsulated organisms (like Streptococcus pneumoniae, Nisseria meningitidis, H.influenzae or E.coli), malarial parasites, babesia
  • Prophylaxis for Post-splenectomy infection:
    • Vaccinate 2-3 weeks before elective splenectomy: Pneumococcal vaccine, Hemophilus influenza type B (Hib) vaccine, Meningococcal group C vaccine, Influenza vaccine
    • Lifelong Antibiotic prophylaxis: Long-term penicillin V 500mg 12 hourly (erythromycin if allergic to penicillin)
    • Revaccination of pneumococcal vaccine: in every 5 years and influenza vaccine anually
    • Antimalarial chemoprophylaxis: if needed (travel to endemic area)
  • Post splenectomy hematological features:
    • Thrombocytosis: persists in 30% cases
    • WBC count: usually normal but there may be mild lymphocytosis and monocytosis
    • Red cell morphology: Howell-Jolly bodies (Nuclear remnants), Pappenheimer bodies (contain sideroblastic granules), Heinz bodies (Denatured hemoglobin), Target cells, Nucleated erythrocyte (occasionally)
Indications for splenectomy
Isolated thrombocytopaenia, haemolytic anaemia or neutropaenia
Painfully enlarged spleen
Traumatic or atraumatic splenic rupture
Splenic artery aneurysm
To allow adjuvant treatment when multiple cytopaenias due to hypersplenism are present
To allow diagnosis in the case of splenomegaly of unclear cause
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