Haematology

Question 1

What proportion of EPO comes from kidneys vs liver?

Answer 1

85% kidneys
15% liver

Also in brain and uterus

Question 2

What is the usual stimulus for EPO secretion?

Answer 2

Hypoxia
Alkalosis
Cobalt salts
Androgens
Catecholamines

Question 3

What percentage of Hb is foetal Hb at birth?

In comparison to adult Hb, what is its affinity to

• 2-3 BPG
• O2

Answer 3

40% at birth
10% at 4 months

• lower affinity for O2
• greater affinity to O2

Question 4

What agglutinins will be present in the following blood types?

• O
• A
• B
• AB

Answer 4

• Anti-A, Anti-B
• Anti-B
• Anti-A
• none

Type A individuals have the A antigen; type B individuals have the B antigen; type AB have both & type O have neither. Infants rapidly develop antibodies against the antigens not present in their own cell.

Question 5

Whihc of Hb vs plasma proteins has the greater buffering capacity?

Answer 5

Hb has a greater buffering capacity not because it works at a pH closer to physiological, but because each Hb has 38 histidine residues to buffer, whereas plasma proteins each only have a carboxyl/amino group.

Hb has 6 x the buffering capacity

Question 6

In which of the following anaemias will you get bone marrow hyperplasia?

• haemolytic
• megaloblastic
• iron deficiency
• chronic disease

Answer 6

• haemolytic: YES increased erthropoesis
• megaloblastic: YES increased levels of growth factors
• iron deficiency: increased erythroid activity in bone marrow, hypochromic microcytic
• chronic disease: poor proliferation in absences of adequate EPO levels

Question 7

10 conditions classically produce intravascular haemolysis?

Answer 7

1. clostridium perfringens infection
2. DIC
3. mechanical heart valves
4. incompatible blood transfusion
5. G6PD deficiency
6. RBC fragmentation
7. Immune hemolytic anaemia (autoimmune, drug, infection)
8. Unstable Hb
9. March Hemoglobinuria
10. Paroxysmal nocturnal hemoglobinuria

Question 8

Which factors are affected in Haemophilia A and Hemophilia B respectively? How common are they?

Answer 8

there is deficiency of factor VIII or factor IX respectively

Haemophilia A happens in 1 in 10,000
Haemophilia B 1 in 30,000