Myeloproliferative disorders

Question 1

Polycythaemia vera

Answer 1

Increased erythropoiesis, independent of EPO production

JAK2 V617F mutation

Itchy after a hot bath

Tx with venesection

Question 2

Relative polycythaemia

Answer 2

Increased hct due to volume loss

Occurs in obesity, alcoholism, diuretics

Question 3

Essential thrombocythaemia

Answer 3

Sustained thrombocythaemia >600x10^9/L

50% have JAK2 V617F mutation

Tx

• aspirin
• anagrelide
• hydroxycarbamide

Question 4

Idiopathic erythrocytosis

Answer 4

• Isolated erythrocytosis with low EPO

- Tx: venesection

Question 5

Myelofibrosis

Answer 5

Clonal proliferation of myelocytes and granulocytes
BM responds with FIBROSIS

DRY TAP + MASSIVE SPLENOMEGALY

Blood film - leukoerythroblastic anaemia, teardrop cells, giant platelets

Tx:

• Supportive
• Hydroxycarbamide
• Thalidomide
• BMT

Question 6

CML

Answer 6

• t(9;22) BCR-ABL
• Massive splenomegaly and raised WCC
• Blood film shows myelocytes, not blasts
• Tyrosine kinase inhibitors (Imatinib is first line)