Other Haem Topics

Question 1

Hepcidin and feroprotin regulate systemic absorption of iron by inhibition of what?

Answer 1

Enterocyte basolateral iron release

Question 2

What are the three forms of iron that can be absorbed from the gut?

Answer 2

• Haem iron
• Ferric iron (Fe3+ reduced to Fe2+ iron at the brush boarder)
• Ferretin

Question 3

Basic pathophysioplogy of anaemia of chronic disease?

Answer 3

Chronic inflammation leads to increased hepcidin production which down regulates iron absorption from the enterocytes leading to anaemia

Question 4

Where is hepcidin produced?

Answer 4

Hepatocytes

Question 5

What are blood film findings of thalasaemia?

Answer 5

Aniso-poikilocytosis (different size and shaped red cells)
Target cells
Contracted cells

Question 6

What is HbH disease?

Answer 6

Alpha thalasaemia in which 3 of the 4 copies of teh alpha globin gene have been lost

Question 7

What is hydrops faetalis?

Answer 7

It is death of the faetus due to no alpha thalamasia in which all copies of the alpha globin gene have been lost. Not compatible with life

Question 8

How many alpha globin genes do you have?

Answer 8

4 copies. 2 copies on each chronasome

Question 9

Features of hyposplenism on blood film?

Answer 9

acanthocytes (spiked cells)
Howel jolly bodies

Question 10

What test is best for distinguishing non immune intravascular haemolysis from AIHA?

Answer 10

Urinary haemosiderin will be increased in non immune. Not increased in AIAH

Question 11

What are some differentials for for low platlets in pregnancy?

Answer 11

Gestational thrombocytopenia
ITP
HELLP
TTP
Pre-eclampsia

Question 12

What platlet level is expected in gestational thrombocytopenia?

Answer 12

almost always >100
- ie someone with a plt of 60 does not have gestational thrombocytopenia

Question 13

What is the highest risk period of thrombosis in pregnancy?

Answer 13

post partum period

Question 14

What tests are abnormal for a pt on theraputic dabigatran? What test is used to detect drug precence / action?

Answer 14

Prolongued thrombin time and APTT

Dilute thrombin clotting time (hemeclot assay)

Question 15

What tests are abnormal for a pt on theraputic rivaroxaban? What test is used to detect drug precence / action?

Answer 15

PT prolonged (varies according to lab)

Modified anti Xa assay specific for rivaroxaban

Question 16

What tests are abnormal for a pt on theraputic Apixaban? What test is used to detect drug precence / action?

Answer 16

PT prolonged or NORMAL (varies according to lab)

Modified anti Xa assay specific for apixaban

Question 17

What is the psychophysiology of TTP?

Answer 17

ADAMTS13 deficiency

ADAMTS13 is a protein that cleaves vWF multimers into smaller sections that then form a organised clot. Pts with TTP have an antibody against ADAMTS13 which results in decreased activity (usually <10%). this means that they retain teh very long multimers of vWF wqhich creates a mesh like network of clot that results in microangiopathic haemolysis

This results in consumption of clotting factors and platlets leading to bleeding
Also results in thrombus formaiton and tissue ischemia

Question 18

What is one of the main side effects of cyclophosphamide?

Answer 18

Bladder irritation and haematuria

Question 19

What is sytemic mastocytrosis? What organs / tissues are affected?

Answer 19

It is a disease characterized by the infiltration of different tissues by clonaly derived Mast cells
- Typically involves Bone marrow, skin, GI tract, liver and spleen

Question 20

What is the characteristic mutation in systemic mastocytosis

Answer 20

c-KIT D816V

Question 21

What specific blood test is typically used to investigate for systemic mastocytosis?

Answer 21

Tryptase level
- will be high in systemic mastocytosis. Normal level does not exclude

Total:beta tryptase ratio > 20:1

Question 22

What can systemic mastocytosis evolve into?

Answer 22

-> Indolent systemic mastocytosis
-> agresive systemic mastocytosis
-> acute mast cell leukaemia

Question 23

What is an important sequelae of burkits lymphoma?

Answer 23

spontaneous TLS due to high doubling rate

Question 24

What is the treatment of TLS?

Answer 24

Monitor urate level and UEC/CMP BD

Treatment:
- Aggressive rehydration
- Allopurinol to control urate level
- Rasburicase if very bad TLS (very expensive alternative to allopurinol)

Question 25

What is the treatment for MTX induced myelosupression?

Answer 25

Folinic Acid (IV preparation)