Haem: Myeloproliferative Disorders

Question 1

Define Myeloproliferative disorders

Answer 1

Clonal proliferation of 1+ mature cell line

Question 2

Philadelphia Chr positive

Answer 2

Chronic Myeloid Leukaemia

Question 3

Philadelphia Chr negative
(3)

What mutation is associated with Ph -ve?

Answer 3

Polycythaemia Vera
Essential thrombocytosis
Primary myelofiborsis

JAK2 (esp in PV)

Question 4

Middle aged
Massive splenomegaly +/- hepatomegaly
BM failure, gout, lethargy, CVA, one eye blindness

Ph+ve (in 80%)
PCR BCR-ABL +ve
WCC 50-500 x 10^9

No blast cells. High neutrophils, mature myelocytes, basophils

Answer 4

Chronic Myeloid Leukaemia

Question 5

Ph Chr translocation?

Answer 5

9;22

Question 6

Chronic myeloid leukaemia definitions for:
Chronic Phase
Acceleration Phase
Blast Phase

Answer 6

Chronic Phase <5% blasts in BM/blood
Tx = IMATINIB (Tyrosine Kinase Inhibitor)

Acceleration Phase >10% blasts in BM/blood
less responsive to therapy

Blast Phase >20% blasts in BM/blood
poor prognosis, may have allogeneic SCT

Question 7

Myeloproliferative disorder
JAK2 Mutation
Ph Chr -ve

Hyperviscosity/hypervolaemia/hypermetabolism
Blurred vision, headache
Aquagenic pruritis

High Hb, Hct +/- N or high WCC and plt
LOW EPO

Answer 7

Polycythaemia Vera

Tx = Venesection + Hydroxycarbamide

Question 8

Myeloproliferative disorder
-> fibrosis of BM or replacement with collagen
Primary (idiopathic) or secondary (after PV, ET, leukaemia)
Ph Chr -ve
Elderly

Pancytopenia (as BM failure)
MASSIVE splenomegaly + systemic Sx 
Budd Chiari-syndrome 
Hyperuricaemia 
Film: Leukoerythroblastic anaemia 

Do BM dry tap

Answer 8

Myelofibrosis

Leukoerythroblastic anaemia = teardrop RBC, high no myeloid blast cells

Tx = support with blood products
Splenectomy if neeses
Hydroxycarbamide, thalidomide, steroids, SCT

Question 9

Myeloproliferative disorder
Ph Chr -ve
megakaryocytes dominate BM
50% have JAK2 mutation

Stroke, MI, gangrene, haemorrhage
Increased bleeding, menorrhagia, headache, visual distrubance

Plt >600 x 10^9
Increased BM megakaryocytes

Answer 9

Essential thrombocythaemia (or thrombocytosis)

Tx = aspirin, Anagrelide (reduce formation plt), Hydroxycarbamide

Question 10

Polycythaemia definition

Answer 10

Raised Hb, Raised hct

as too many RBC

Question 11

Primary (true) Polycythaemia causes

normal plasma, high Hb

Answer 11

Polycythaemia Vera (myeloproliferative disorder)
Familial Polycythaemia

Question 12

Secondary (true) Polycythaemia causes

normal plasma, High Hb

Answer 12

high EPO
non malignant causes
Renal Ca, high altitude, chronic hypoxia e.g. COPD, uterine myoma

Question 13

Relative Polycythaemia causes

Answer 13

relative is when looks like high Hb, but Hb is normal, just plasma that is low

Causes = obesity, alcohol, diuretics
often in elderly