Definition and Background
Normally, the spleen weighs 150g and its craniocaudal length is approximately 11 cm. The spleen is not a vital organ; the body can manage without the spleen all immune reactions and utilization of redundant erythrocytes; the liver can adopt and take over all functions of the spleen when it is removed due to particular reasons (injury, blood diseases).
The spleen consists of the two formations: the red pulp and the white pulp that are covered by a dense fibrous covering called the splenic capsule.
The white pulp is the place where white cells grow and mature (extramedular hemopoiesis); the red pulp filters damaged red cells, hosts microgages and platelets, releasing them when it is necessary into the blood stream.
Also, the spleen is responsible for the synthesis of immunoglobulin G (IgG), properdin taking part in compliment activation and tuftsin (an immunostimulatory tetrapeptide).
Causes of splenomegaly include:
- Haematological: Chronic myeloid leukaemia (CML), Chronic lymphocytic leukaemia (CLL), Acute leukaemia lymphoma, Primary myelofibrosis, Polycythaemia vera, Hairy cell leukaemia, Thalassaemia major or intermedia, Sickle cell anaemia (before splenic infarction), Haemolytic anaemias, Megaloblastic anaemia.
- Portal hypertension: Cirrhosis Hepatic, Portal, Splenic vein thrombosis, Storage diseases, Gaucher’s disease, Niemann–Pick disease.
- Histiocytosis X
- Systemic diseases: Sarcoidosis, Amyloidosis, Collagen diseases – Systemic lupus erythematosus, Rheumatoid arthritis
- Systemic mastocytosis
- Infections: Severe septicaemia, Bacterial endocarditis, Typhoid, Infectious mononucleosis; Chronic: Tuberculosis, Brucellosis, Syphilis, Malaria, Leishmaniasis, Schistosomiasis Tropical: Malaria (massive (>20 cm) splenomegaly)
In the USA, it is reported that, in 2% – 5.6% of patients, a palpable spleen is found. Tropical splenomegaly syndrome is detected the most frequently in persons who have a close affiliation to the countries where malaria causes a great concern (tropical Africa, as well as visitors to that region).
Tropical splenomegaly syndrome (or hyperactive malarial syndrome) – there is a female-to-male incidence ratio of 2:1. Normally, the capsules of spleens in older people are much thinner than in a younger group. This combination of factors: capsular thinning, increased spleen weight and size, makes the occurrence of splenic injury more common in elderly persons; thus, the likelihood of splenectomy for trauma in this subgroup becomes more probable.
These symptoms are usually found in the patients with splenomegaly:
- Pallor (very pale skin surfaces)
- Fatigue, feeling permanently exhausted
- Easy bruising (little petechial rash or merging bruises all over the body)
- Sweats, without fever or with
- Weight loss, sometimes significant in advanced forms of malignant processes
- Stomach-ache, abdominal distention
- Pancreatic symptoms (in the case of the splenic vein thrombosis)
- Breathlessness, as ascetic symptoms become more prominent
The hallmarks and predisposed factors in the anamnesis of the patients with supposed splenomegaly are:
- Severe infections (Epstein–Barr virus contributes to the enlargement of the organ)
- Trauma (transport accidents and fights)
- Family history of malignancies (lymphomas in the anamnesis)
- Family history of blood diseases (leukemias and amenias)
- Travel history (tropical countries with outbreaks of malaria)
- Risk factors of infectious hepatitis (B and C)
- Family history of connective tissue disease (autoimmune diseases)
Normally, the spleen is not palpable, apart from young children and adolescents, also those people who have specific body anatomy. Liver failure symptoms have to be taken into account while diagnostics
Lymphadenopathy may lead physicians to the thought of a cancerous process in the bone marrow and the whole lymph system.
Skin symptoms may appear, including petechial rash and bruising.
A spleen weighing over 400-500 gm and the length of the spleen exceeding 15-20 cm is considered to be enlarged. A mega-enlarged spleen is the one the weight of which account for over 1000gm.
Splenomegaly is more a symptom rather than a full diagnosis, thus may accompany numerous conditions; in most cases associated with neoplasm growth or autoimmune disorder.
- CBC may reflect low vice versa high blood count, depending on the condition associated with the enlargement of the spleen.
- A liver function test is elevated when there are symptoms of portal arteries hypertension.
- Urea and electrolytes might be elevated as well as the multi-organ failure grows.
- LDH may be increased when the splenomegaly is associated with malignant neoplasms growth.
- Autoimmune screen and inflammatory markers is necessary in order to exclude the connective tissue diseases, which may trigger the enlargement of the organ.
- Ultrasound examination of the abdomen
- CT of the abdomen
- Bone marrow aspirate
- Lymph node biopsy
- Full liver screen
Massive splenomegaly associated with listed below conditions for a differential diagnosis:
- Myeloproliferative disease
- Portal vein obstruction/portal hypertension
- Niemann-Pick disease
- Gaucher disease 
- Hereditary spherocytosis
- Thalassemias – major, alpha or beta
- Histiocytosis X
Moderate splenomegaly includes all the listed above conditions for the differential diagnosis, including these next ones:
- Severe bacterial sepsis
- Infective endocarditis
- Sickle cell anemia
- Secondary to severe infection splenic abscess
- Acute infectious illnesses (typhoid, malaria, other tropical diseases)
- Acute viral infections (infectious mononucleosis)
- Systemic lupus erythematosus
- Tuberculosis (chronic forms)
- Angioimmunoblastic lymphadenopathy
- Banti disease
- Congestive heart failure due to cirrhosis
- Drug reactions with serum sickness syndromes
- Idiopathic splenomegaly
- Immune hemolytic anemia
- Immune thrombocytopenic disorders
- Leukocyte disorders
- Splenic vein obstruction
- Symptomatic human immunodeficiency virus (HIV) infection
There is another option, namely conservative management of splenomegaly, which includes blood transfusions/exchange transfusions that are performed in order to reduce the number of sickled red blood cells, or refrain from a splenectomy.
Low-dose radiotherapy has been used as palliative care in patients with advanced hematological problems (primary myelofibrosis).
Some cases of splenomegaly require the removal of the organ, as its malfunction may cause even more severe consequences as it may become a reason of the aggravation of the basic condition.
Indications for splenectomy:
- Trauma causing splenic rupture
- Chronic immune thrombocytopenia
- Hemolytic anaemia (massive hemolysis of red cells, the spleen is packed with the cells), including Autoimmune hemolytic anaemia, thalassemia major or intermediate
- Hereditary spherocytosis (Sickle cell disease), here splenectomy may prevent further sequestration and may reduce the relapse of an acute splenic sequestration crisis. However, recent research states a doubt regarding splenectomy as a means of improvement of survival and decreases morbidity in sickle cell disease.
- Chronic lymphocytic leukemia (CLL) and lymphomas
- Primary myelofibrosis
- Tropical splenomegaly
The correct answers can be found below the references.
1. A patient, a 27 year old man, was brought by an ambulance from the place of a car accident, and he is unconscious. The CBC reveals pancytopenia, hematocrit 23% (N for males 40-54%). The skin is pale and, in the left part of the abdomen, there is a palpable mass. A helical CT scan detected an intra-parenchymal blush in the spleen area.
What is the most probable diagnosis? What is the most appropriate management for the condition?
- Spleen rapture/Splenectomy
- Spleen rapture/Fluid infusion
- None of the above
- An Afro-American patient
2. A 20 year old complains about the deterioration of his general condition, namely weight loss, fatigue, yellow color of the skin, poor appetite and dizziness. His hands and feet are swollen. History: the patient frequently contracts infectious diseases, and easily bruises. A CBC reveals: hemoglobin S and numerous deformed red blood cells (sickle-shape). What is the most probable primary diagnosis? What imaging findings would follow this condition?
- Sickle cell anemia/hepatosplenomegaly
- Hemolytic anemia/hepatosplenomegaly
- Hodgkin`s lymphoma/hepatosplenomegaly
- Non-Hodgkin`s lymphoma/hepatosplenomegaly
3. A 58 year old male patient complains about vomiting, nausea, weight loss, abdominal pain and “heaviness” in the right side of the abdomen. History: he abuses alcohol; his brother suffers from hemolytic anemia. Physical examination: There are obvious signs of cirrhosis, namely caput medusa, ascites, jaundice, telangiectasias; heart murmur witnessing congestive heart failure. A CT reveals an enlarged spleen. What is the most probable reason for the spleen enlargement, and what scale of the enlargement would be found in this patient?
- Splenic vein obstruction due to cirrhosis/moderate splenomegaly
- Splenic vein obstruction due to cirrhosis/massive splenomegaly
- Portal vein obstruction/moderate splenomegaly
- Portal vein obstruction/moderate splenomegaly
- None of above