The Spleen

Question 1

the spleen is made up of

Answer 1

red pulp and white pulp

Question 2

The spleen is one of the main organs in the

Answer 2

reticuloendothelial system (RES), who’s function is to identify and act against foreign pathogens (using phagocytic cells).

Question 3

All of the body’s blood passes through the spleen

Answer 3

via the splenic artery, and the reticuloendothelial (RE) cells filter it.

Question 4

red pulp

Answer 4

removes old red blood cells and metabolises haemoglobin

- made up of endothelial macrophages

Question 5

white pulp

Answer 5

similar structure to lymphoid tissue- removes any bacteria and erythrocytes coated in antibodies.

Question 6

White cells and plasma preferentially pass through the ……. pulp and red blood cells through the ….. pulp.

Answer 6

1) white

2) red

Question 7

functions of the spleen

Answer 7

1) Sequestration and phagocytosis
2) Blood pooling
3) Extramedullary haemopoiesis
4) Immunological function

Question 8

Sequestration and phagocytosis

Answer 8

red cells removed by macrophages

Question 9

Blood pooling

Answer 9

Platelets and red cells can be rapidly mobilised during bleeding

Question 10

Extramedullary haemopoiesis

Answer 10

a. Pluripotential stem cells proliferate during haematological stress or if marrow fails (haemopoesis in the spleen opposed to bone marrow e.g. thalassaemia)
b. Spleen will increase in size

Question 11

Immunological function

Answer 11

25% T cells and 15% B cells stay in the spleen

Question 12

blood enters the spleen via the

Answer 12

splenic artery

Question 13

examination of the spleen

Answer 13

never normal form the spleen to be palpable below the costal margin

• start to palpate the rich iliac fossa
• feel for spleen edge moving towards your hand on inspiration
• feel for the splenic notch
• measure in CM from costal margin in mid-clavicular line

Question 14

Splenomegaly

Answer 14

– Enlargement of the Spleen

Question 15

Splenomegaly usually occurs when

Answer 15

the spleen has an increased workload (e.g. overworking red or white pulp).

e.g. systemic infection/ parasitic

Question 16

other causes of splenomegaly

Answer 16

• Back pressure due to portal hypertension.
• Infiltrated by foreign cells – cancer cells of blood origin (e.g. leukaemia) and other cancer metastases; infectious diseases (e.g. malaria, schistosomiasis and HIV).

Question 17

risk of splenomegaly

Answer 17

As it is no longer protected by the ribs, the risk of rupture is increased. This could cause a haematoma

*must avoid contact sports *

Question 18

why can low blood count occur in hypersplenism

Answer 18

low blood counts can occur due to pooling of blood in enlarged spleen

Question 19

causes of hyposplenism

Answer 19

• Splenectomy
• Sickle cell disease-
• GI disease
• Autoimmune disorders

Question 20

splenectomy

Answer 20

may be required due to splenic rupture from trauma or because of cancer

Question 21

sickle cell disease

Answer 21

in older children and adults due to multiple infarcts and fibrosis

Question 22

GI disease

Answer 22

o Coeliac disease
o Crohns disease
o UC

Question 23

Autoimmune disorders

Answer 23

o Systemic lupus
o Rheumatoid arthritis
o Hashimotos disease

Question 24

Hyposplenic or asplenic patients have an increased risk of…

Answer 24

of developing sepsis, especially from encapsulated organisms

This is because the white pulp can no longer remove the bacteria and therefore they remain in the body, allowing them to cause further infection.

Patients are usually given various vaccinations to compensate for this and lifelong prophylaxis antibiotics

Question 25

encapsulated organisms

Answer 25

Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae

Question 26

A blood film for hyposplenic patients would contain

Answer 26

Howell-Jolly bodies (red blood cells with remnants of DNA still in the cytoplasm).

Question 27

Howell-Jolly bodies are indicative of

Answer 27

of damage as a functioning spleen would remove these as they passed through.