Haematology

Question 1

What does a raised reticulocyte count tell you about the general cause of anaemia?

Answer 1

It is a problem with removal of RBCs.

Question 2

What does a decreased reticulocyte count tell you about the general cause of anaemia?

Answer 2

It is a problem with production of RBCs.

Question 3

Give three events that happen as a red blood cell matures.

Answer 3

• Size decreases
• Cytoplasm ratio decreases
• Nucleus disappears

Question 4

What is the lifespan of an erythrocyte?

Answer 4

120 days

Question 5

What is the lifespan of a platelet?

Answer 5

7-10 days

Question 6

Describe the four globin chains on adult haemaglobin.

Answer 6

2 alpha chains

2 beta chains

Question 7

Describe the four globin chains in foetal haemoglobin.

Answer 7

2 alpha chains

2 gamma chains

Question 8

Describe how the gamma globin chain differs from alpha and beta chains.

Answer 8

It has a much stronger affinity for oxygen.

Question 9

Give a disease in which abnormal qualities of Hb are produced.

Answer 9

Sickle cell

Question 10

Give an disease where abnormal quantities of Hb are produced.

Answer 10

Thalassaemia

Question 11

What is meant by MCV?

Answer 11

Mean corpuscular volume - the average volume if the red blood cells in a sample.

Question 12

What is meant by MCH?

Answer 12

Mean corpuscular haemoglobin - the average amount of haemoglobin in each red blood cell.

Question 13

What is meant by MCHC?

Answer 13

Mean corpuscular haemoglobin concentration - the average concentration of haemoglobin in each red blood cell

Question 14

What is meant by the haematocrit?

Answer 14

The percentage of blood volume which is red blood cells.

Question 15

Name the cell from which platelets are derived.

Answer 15

Megakaryocytes

Question 16

What is platelet production regulated by?

Answer 16

Thrombopoietin

Question 17

Where is thrombopoietin produced?

Answer 17

Liver

Question 18

What is the normal platelet count?

Answer 18

150-400x10^9 /L

Question 19

How are platelets removed from the blood stream?

Answer 19

By the spleen

Question 20

Which receptor attaches platelets to collagen?

Answer 20

GP1b

Question 21

Which receptors attach platelets to von Willebrand factor?

Answer 21

GP1b and GpIIb/IIIa

Question 22

Name four things that are released from platelets when they degranulate.

Answer 22

• ADP
• Fibrinogen
• Thrombin
• Calcium

Question 23

How do platelets facilitate healing?

Answer 23

They release platelet derived growth factor (PDGF).

Question 24

Give two ways that hepcidin lowers iron concentration in the blood.

Answer 24

• Decreases intestinal absorption

- Inhibits degradation of RBC by macrophages so iron can’t be recycled

Question 25

How does chronic disease lower iron concentration in the blood?

Answer 25

Inflammatory cytokines promote hepcidin production by the liver.

Question 26

Give one way to tell the difference between iron deficiency anaemia and anaemia of chronic disease.

Answer 26

Ferritin is low in iron deficiency and high in anaemia of chronic disease because it is an acute phase protein.

Question 27

Why does autoimmune haemolysis occur in chronic lymphocytic leukaemia?

Answer 27

B cells produce faulty antibodies which can attack red blood cells.

Question 28

Describe myelodysplastic syndrome.

Answer 28

Failure of the bone marrow, in which immature blast cells are produced but do not proliferate (like in leukaemia).

Question 29

Give a virus which is associated with the development of lymphoma?

Answer 29

Epstein Barr Virus

Question 30

Describe myelofibrosis.

Answer 30

Fibrosis of the bone marrow due to hyperplasia of abnormal megakaryocytes, which produce platelet derived growth factor to stimulate fibroblasts.

Question 31

Why does itching occur in polycythaemia?

Answer 31

Heat causes degranulation of mast cells, and as more are produced, more histamine is released.

Question 32

What is hydroxycarbamide/hydroxyurea used in?

Answer 32

- Sickle cell anaemia - Leukaemia - Polycythaemia

Question 33

Name the monoclonal antibody against tyrosine kinase which is used in CML.

Answer 33

Imatinib/Gleevec

Question 34

Name a cytotoxic drug against blood cells.

Answer 34

Hydroxycarbamide/Hydroxyurea

Question 35

Why do hepatomegaly and splenomegaly occur in myelofibrosis?

Answer 35

The liver and spleen take on the role of producing blood cells.