myelofibrosis

Question 1

pathology

Answer 1

• mutation in haematopoitic progenitors - JAK2 (primary)
• activated jak stat pathway
• leading to overproduction of megakaryocytes
• these release cytokines attracting fibroblasts
• fibrobasts undergo fibrosis making scar tissue in bone marrow
• the scarring causes ineffective haematopoisis - low RBC, abnormal WBC and platelets
• this causes blood cell production to shift to liver and spleen causing enlargement of these

secondary
- essential thrombocythemia
- polycythemia vera

Question 2

testing

Answer 2

RBC, WBC platelet count
genetic testing
ultrasound of spleen
bone marrow aspirate and biopsy

Question 3

treatment

Answer 3

• ruxolintinb (JAK2 inhibitor)
• erthythropoiten injections for anaemia
• anagelsia for splenic discomfort
• blood transfusion for (pancytopenia) support if required
• haematopoitic stem cell transplant - potential cure

Question 4

symptoms

Answer 4

bone pain
weight loss
fever
itching
hepatomegaly
fatigue - anaemia
infections - keukopenia

Question 5

level of blood cells

Answer 5

initial inc in all blood cells esp plateletys
drop then

Question 6

blood smear findings

Answer 6

• teardrop rbc
• immature rbc
• nucleated rbc
• immiture wbc
• immateure platelets

rbc called poikilocytosis - meaning irregularly shaped

Question 7

biopsy findings

Answer 7

early myelofibrosis:
- inc in haematopoeitic stem cells

later myelofibrosis:
- dec in haematopoietic cell number
- fibrosis

dry tap

Question 8

JAK2

Answer 8

60% patients are JAK2 positive