Download Problem 05- Enlarged Spleen

Basic Medical Sciences
Rotation of stomach liver and spleen occurs between the 6th-11th week of embryology.
Normally the spleen weighs 200g and is the largest lymphoid organ in the body, it is oval in shape
and is located between the 9th and 11th rib.
Two anatomical components: Red pulp (consists of sinuses lined by endothelial macrophages and
cords (spaces). White pulp (structure similar to lymphoid follicles)
The spleen plays an important role immune defence and removes expired or abnormal blood cells.
4 Key Functions
1) Removal of old or abnormal RBCs
2) Proliferation of stem cells in severe haematological stress (e.g. haemolytic anaemia or
thalassaemia major)
3) Immunilogical function (25% T-lympocytes and 15% B-lymphocytes present in spleen. Spleen
shared production of antibodies with other lymphoid tissue.
4) Blood pooling (up to 1/3 of platelets are pooled by the spleen and can be rapidly mobilised if
needs be).
Reticulo-endothelial system- This is concerned with the defence against microbial infection and the
removal of worn out red blood cells from the blood stream. It is a community of cells including
phagocytes, macrophages and monocytes. The spleen plays a key part in this system.
Clinical Sciences
Hyperspienism- excess removal of blood cells leading to pancytopenia
The term asplenia refers to the absence of the spleen, a condition that is rarely congenital and
mostly post-surgical.
Differential diagnosis of enlarged spleen
Broadly speaking, there are five things that an enlarged spleen is likely to be caused by: infection,
haematological cancer, abnormal blood flow, increased RBC removal, or autoimmune. (More
rarely, blood disorders resulting in increased RBC removal, such as haemolytic anaemias, will result
in an increase in spleen size.)
Infection

Viral - this is usually infectious mononucleosis, CMV, malaria, HIV or hepatitis.

Bacterial - endocarditis or some forms of TB.
Blood Flow

This is caused by some form of blockage or other backflow. Liver cirrhosis, right heart failure,
sickle cell anaemia (can cause small spleen due to infarct) and schistosomiasis.
Haematological cancer

Essentially, any of the haematological cancers can cause an enlarged spleen. These are
leukaemia and lymphoma by and large.
Increased RBC removal

The spleen is involved in the breakdown of red blood cells. In a condition where lots are
being broke down (haemolysis), the spleen is part of that breakdown process. It gets bigger
in order to deal with the extra RBCs it's breaking down.
Autoimmune

Any connective tissue disorder which is autoimmune: rheumatoid arthritis, SLE or
sarcoidosis are all examples.
Portal Hypertension due to Cirrhosis
Portal hypertension is an increase in the blood pressure within a system of veins called the portal venous
system. Normally, the veins come from the stomach, intestine, spleen, and pancreas, merge into the portal
vein, which then branches into smaller vessels and travels through the liver. If the vessels in the liver are
blocked, it is hard for the blood to flow causing high pressure in the portal system.
The most common cause of portal hypertension is cirrhosis of the liver. Cirrhosis results from scarring of a
liver injury caused by hepatitis, alcohol abuse, or other causes of liver damage. In cirrhosis, scar tissue
blocks the flow of blood through the liver.
Other causes of portal hypertension include blood clots in the portal vein, blockages of the veins that carry
the blood from the liver to the heart, and a parasitic infection called schistosomiasis. Sometimes the cause
is unknown.
Behavioural Sciences
Medi-alert post splenectomy... SEPSIS (most commonly from Streptococcus pneumoniae, also
known as the pneumococcus).
In people without a spleen or with abnormal spleen function, symptoms of sepsis may develop
quickly following a minor infection, such as a RTI. Early symptoms of a respiratory infection can
include throat or chest pain, coughing, ear pain, or sinus pain and congestion.
In other cases, sepsis develops abruptly. People without a functional spleen should begin antibiotic
treatment and seek medical care at the earliest sign or symptom of sepsis including the following:

Fever greater than 100.4ºF or 38ºC

Uncontrollable chills and/or shivering

Headache

Drowsiness, confusion, and/or disorientation

Nausea, vomiting, and/or diarrhea

Severe abdominal pain

Pinpoint purplish red spots on the skin (petechiae) or larger, bluish bruises

Low blood pressure, lightheadedness or fainting (syncope)

Rapid heart rate
Risk of sepsis — If the spleen stops working normally or is surgically removed, the body's immune
system can usually compensate. However, there is a small but significant risk of sepsis (particularly
first 2yrs post splenectomy). Lifetime risk is 1-2%
The risk of sepsis is highest in the following groups:

Children whose spleen is removed during infancy

People with lymphoma who are treated with splenectomy, radiation, and chemotherapy
Population Health Sciences
Patients are immunocompromised by the operation so be on penicillin V for 2yr post-splenectomy.
Should start amoxicillin at first sign of infection.
Pre-op patients should have pneumococcal, haemolphilus type B and meningitis A+C vaccines (if
necessary can be post op) and yearly flu vaccines post op.
Index conditions
Common or less common but dangerous
Portal hypertension due to cirrhosis (see above pathophysiology and causes)
Diagnosis
Treatment
GI bleeding (varices), Ascites, Encephalopathy
(confusion and forgetfulness caused by poor
liver function, reduced platelet count.
Treatment of the cause. May involve lifestyle
changes, medication, endoscopic therapy
(banding or sclerotherapy for variceal bleeding)
If these do not work.

Transjugular intrahepatic portosystemic
shunt (TIPS): This procedure involves placing
a stent (a tubular device) in the middle of the
liver. The stent connects the hepatic vein
with the portal vein.

Distal splenorenal shunt (DSRS): This
procedure connects the vein from your
spleen to the vein from your left kidney in
order to reduce pressure in the varices and
control bleeding.
Haemological malignancies
Leukaemias and lymphomas (hodgkins and non hodgkins)
Diagnosis
Blood count and blood film. In lymphadenopathy
a lymph node biopsy is undertaken.
Treatment can occasionally consist of "watchful
waiting" (e.g. in CLL) or symptomatic treatment
(e.g. blood transfusions in MDS). The more aggressive
forms of disease require treatment
with chemotherapy, radiotherapy, immunotherapy and
- in some cases - a bone marrow transplant.
Treatment
Haemological disorders
Includes: Anaemia, Thrombocytopenia,Neutropenia Etc.
Less common but illustrative
Infiltrative (e.g. amyloid)
Amyloidosis
This refers to a variety of conditions in which amyloid proteins are abnormally deposited in organs and/or tissues.
A protein is described as being amyloid if, due to an alteration in its secondary structure, it takes on a particular
aggregated insoluble form similar to the beta-pleated sheet.
Amyloidosis can occur as an isolated disease or secondary to another illness e.g.Myeloma
Clinical features
Symptoms in patients with amyloidosis result from
abnormal functioning of the particular
organs.involved. E.g. Heart: Arrhythmia, heart
failure. Lungs: Haemoptosis. Spleen:
enlargement and rupture.
If the diagnosis of amyloidosis is suspected,
a biopsy (tissue sample) of suspected organ is
ideal. A biopsy of abdominal wall fat,
the rectum or a salivary gland can be examined
for evidence of characteristic systemic amyloid
deposits. The most useful stain in the diagnosis
of amyloid is Congo red, which combined
with polarized light makes the amyloid proteins
appear apple-green on microscopy.
Diagnosis
Treatment
Initial treatment of amyloidosis involves correcting
organ failure and treating any underlying illness
(such as myeloma, infection, or inflammation)
Infective (e.g. malaria and infectious mononucleosis)
Infectious mononucleosis (glandular fever)
Clinical features
Diagnosis



Droplet transmission (30-50 days incuabation period)
Assymptomatic in childhood but most common in adolescents
Fever, malaise, pharyngitis and cervical lymphadenopathy.
Petechiae might be seen on palate and sparse macularpapular rash
may occur.
 Slenomegaly is present in 50% cases and hepatomegaly with
hepatitis in 10%
 Infection can persist for 3 months
 Florid rash may occur in amoxicillin is given
Usually clinical
Specific EBV serology- IgM to viral capsid antigen
Management
Blood shows atypical lymphocytes and heterophile antibody (basis for
agglutination tests like monospot and Paul-Bennel tests- nb only appears in
second week and may not at all in young children)
Symptomatic Rarely massive pharyngeal swelling can compromise air way
(corticosteroid treatment helps this)