Polycythaemia Vera

Question 1

Primary and Secondary causes of polycythaemia

Answer 1

Primary:
polycythaemia rubra vera

Secondary:
- COPD
- altitude
- obstructive sleep apnoea
- excessive EPO

Question 2

What is polycythaemia vera?

Answer 2

myeloproliferative disorder

• clonal proliferation of stem cells leading to an increase in red cell volume

Question 3

At what age do most patients develop polycythaemia vera

Answer 3

60s

Question 4

What mutation is associated with Polycythaemia vera?

Answer 4

JAK2

Question 5

Clinical features of polycythaemia

Answer 5

pruritus (typically after hot bath)
splenomegaly
hypertension
hyperviscosity
arterial thrombosis
venous thrombosis
haemorrhage (secondary to abnormal platelet function)

Question 6

Investigations for diagnosis of polycythaemia vera

Answer 6

FBC/film (raised haematocrit)

JAK2 mutation

serum ferritin

renal and liver function tests

Question 7

What tests are useful for polycythaemia vera if JAK2 is negative?

Answer 7

red cell mass
arterial oxygen saturation
abdominal ultrasound
serum EPO level
bone marrow biopsy
cytogenetic analysis
erythroid burst-forming unit (BFU-E) culture

Question 8

Management of Polycythaemia Vera

Answer 8

aspirin - lowers thrombotic risk
venesection - lowers Hb
chemotherapy - hydroxycarbamide

Question 9

What other conditions can polycythaemia progress to?

Answer 9

5-15% of patients progress to myelofibrosis

5-15% of patients progress to acute leukaemia