Myeloproliferative Disorders

Question 1

What is myelofibrosis?

Answer 1

Hyperplasia of megakaryocytes causes secretion of platelet-derived growth factor.

Platelet-derived growth factor activates fibroblasts causing fibrosis of bone marrow, therefore haematopoiesis occurs in spleen and liver.

Question 2

What is the presentation of myelofibrosis?

Answer 2

Anaemia with massive hepato-splenomegaly.

Typically in an elderly person

Question 3

What do tear-drop poikilocytes indicate on blood film?

Answer 3

Myelofibrosis

Question 4

What would the result of a bone-marrow biopsy be in myelofibrosis?

Answer 4

Inconclusive aș unable to take sample.

Question 5

What lab results are expected in polycythaemia vera? (3)

Answer 5

High red cell volume (high haematocrit)
High neutrophils
High platelets in 50%

EPO low, unlike secondary polycythaemia.

Question 6

What are the main symptoms of polycythaemia vera?

Answer 6

Pruritis (after hot bath especially)
Splenomegaly
Haemorrhage
Plethoric appearance (red face)
Hypertension in 1/3
Low ESR

Question 7

What is the mutation in polycythaemia vera?

Answer 7

JAK2 mutation

Question 8

What is the management of polycythaemia vera?

Answer 8

Aspirin - reduced risk of thrombosis
Venesection
Chemotherapy