Haematology

Question 1

What chromosomal abnormality is seen in CML?

Answer 1

Philadelphia chromosome (BCR-ABL) - a translocation between the long arm of chromosome 9 and 22

Question 2

What is the first line treatment of CML?

Answer 2

Imatinib - this is an inhibitor of the tyrosine kinase associated with the BCR ABL defect

Question 3

What are the four main types of sickle cell crisises?

Answer 3

1. Thrombotic
2. Sequestrian
3. Aplastic
4. Haemolytic

Question 4

What virus causes an aplastic crisis in sickle cell anaemia?

Answer 4

Parovirus

Question 5

What is a sequestrian crisis in suckle cell anaemia?

Answer 5

Sickling within organs such as the spleen or lungs which then causes pooling of the blood with worsening anaemia.

Question 6

What is an aplastic crisis in sickle cell anaemia?

Answer 6

A sudden fall in haemoglobin caused by an infection with parovirus.

Question 7

What is an thrombotic crisis in sickle cell anaemia?

Answer 7

also known as painful crises or vaso-occlusive crises
A crisis precipitated by infection, dehydration, deoxygenation
infarcts occur in various organs including the bones (e.g. avascular necrosis of hip, hand-foot syndrome in children, lungs, spleen and brain

Question 8

What is glucose 6 phosphate dehydrogenase deficiency?

Answer 8

• Commonest red blood cell defect
• More common in people from the Mediterranean and Africa
• X linked recessive

Low levels of G6PD which means less glutathione which means the red blood cells are more susceptible to oxidative stress.

Many drugs (and fava beans) can precipitate a crisis. Features of a crisis include haemolysis, jaundice and splenomegaly.

Can cause neonatal jaundice

Can cause gallstones

Heinz bodies on blood films

Diagnosis by using a G6PD assay.

Question 9

What is hereditary spherocytosis?

Answer 9

Autosomal dominant condition where there red blood cells are shaped like spheres instead of biconcave discs.

Causes chronic symptoms but infection an precipitate a haemolytic crisis.

Tested for using an osmotic fragility test.

managed with folate replacement and splene3ctomy

Question 10

What is aplastic anaemia? What can cause it?

Answer 10

Pancytopenia and a hypoplastic bone marrow

Normochromic normocytic anaemia

can be idiopathic, caused by drugs (phenytoin and chloramphenicol) infection (parovirus, hepatitis) and radiation.

Question 11

What is idiopathic thrombocytopenic purpura?

Answer 11

Immune mediated reduction in the platelet count. Antibodies are made aginst glycoprotein IIb.IIIa complex.
It can be acute (more commonly seen in children following an infection or vaccination and it self limiting) or chronic (more common in young women and runs a relapsing remitting course)

Question 12

What is factor V leiden deficiency?

Answer 12

activated protein C resistance. Thisis the most common inherited thrombophilia. It causes activated factor V (a clotting factor) to be inactivated more slowly by activated protein C. This then increases the tendency to clot.

Question 13

What is von willebrands disease?

Answer 13

Most common inherited bleeding disorder. Autosomal dominant. Platelet disorder (less platelet aggregation)
Tranexemic acid can be given for mild bleeding. Desmopressin ca riase levels of von willebrand factor

Question 14

What are the different types of sickle cell crisis?

Answer 14

1. Thrombotic
   - Painful
   - precipitated by infection, dehydration and deoxygenation
   - Infarcts occur in the organs and bones
2. Sequestrian
   - Cickling within organs such as the spleen or lungs causing pooling of blood with worsening of anaemia
3. Aplastic
   - caused by partovirus infection
   - Sudden fall in haemoglobin
4. Haemolytic
   - rare
   - fall in haemoglobin and increased haemolysis

Question 15

What is hereditary haemorrhagic telangectasia?

Answer 15

An autosomal dominant condition characterised by multiple telangiectasia over the skin and mucous membranes. 4 main diagnostic criteria are:

1. Epistaxis
2. Telangiestasis
3. Visceral tract lesions
4. Family history