Myeloproliferative Neoplasms/Disorders

Question 1

What are MPNs?

Answer 1

rapid growth of granulocytes, red cells and platelets

maturation is preserved

Question 2

How do MPNs present on investigation?

Answer 2

high granulocyte count
high red cell count/Hb
high platelet count
eosinophilia/basophilia
splenomegaly
thrombosis in unusual places

Question 3

What are examples of MPNs?

Answer 3

Chronic myloid leukaemia
Polycythaemia Vera
Myelofibrosis
essential thrombocythaemia

Question 4

What diferentiates MPNs?

Answer 4

BCR-ABL 1 gene

Question 5

What MPNs are BCR-ABL 1 gene positive?

Answer 5

CML

Question 6

What MPNs are BCR-ABL 1 gene negative?

Answer 6

Polycythaemia Vera
Myelofibrosis
essential thrombocythaemia

Question 7

What is PV?

Answer 7

high Hb/Hct accompanied by erythrocytosis but can also have excessive production of other lineages

Question 8

How does PV present?

Answer 8

headache
fatigue
itch
increased blood viscosity

Question 9

What is a common mutation found in PV? What does it cause?

Answer 9

JAK 2 - leads to loss of auto inhibition and activation of erythropoesis in the absence of a ligand

Question 10

How is PV treated?

Answer 10

venesect to Hct <0.45
aspirin
cytotoxic oral chemo

Question 11

What are differentials of PV?

Answer 11

secondary polycythaemia - chronic hypoxia, smoking, EPO secreting tumours
pseudopolycythaemia - dehydration, diuretic therapy, obesity

Question 12

What is essential thrombocythaemia?

Answer 12

uncontrolled proliferation of abnormal platelets

Question 13

How does essential thrombocythaemia present?

Answer 13

bleeding and classical MPN features

Question 14

What are the genetics behind essential thrombocythaemia?

Answer 14

20% of pts will have triple negative - JAK2, CALR, MPL

Question 15

How is essential thrombocythaemia treated?

Answer 15

antiplatelets - aspirin

cytoreductive therapy to control proliferation - hydroxycarbamide, interferon alpha

Question 16

What is Myelofibrosis?

Answer 16

MPN that causes extensive scarring in the bone marrow

Question 17

What are the 3 types of myelofibrosis?

Answer 17

idiopathic
post polycythaemia
essential thrombocythaemia

Question 18

How does myelofibrosis present?

Answer 18

marrow failure
splenomegaly
hypercatabolism

Question 19

What does myelofibrosis look like on blood film?

Answer 19

tear drop shaped RBCs and leucoerythroblastic picture

Question 20

What is a leucoerythroblastic film?

Answer 20

presence of immature erythrocytic and neutrophilic precursors in the peripheral blood

Question 21

What can cause a leucoerythroblastic film?

Answer 21

reactive - sepsis
marrow infiltration
lymphoma
severe bleeding
shock 
myelofibrosis

Question 22

How is myelofibrosis treated?

Answer 22

supportive - blood transfusion, platelets, antibodies
allogenic stem cell transplant
JAK2 inhibitors
splenectomy

Question 23

What can a splenectomy treat?

Answer 23

ITP and AIHA

Question 24

What must you vaccinate against if you give a splenectomy?

Answer 24

meningococcus
H. influenzae type B
penumococcus

Question 25

Why do you need to vaccinate after doing splenectomy?

Answer 25

spleen is needed for immunity against encapsulated organisms