Other myeloid disorders

Question 1

MYELOPROLIFERATIVE DISORDERS
i) what are they? what do they have the potential to progress to?
ii) what is primary myelofibrosis a result of? what is PCV a result of? what is essential thrombocytopenia a result of?
iii) name three genes that are implicated in MPDs
iv) name three systemic symptoms they may px with?

Answer 1

i) uncontrolled proliferation of a single type of stem cell > potential to progress to AML
ii) PM due to prolif of haematopoeitc stem cells
PCV prolif of erythroid cells
ET prolif of megakaryotic cell line
iii) JAK2, MPL, CALR
iv) fatigue, WL, NS, fever

Question 2

MYELOFIBROSIS
i) what three things can it be a result of? what happens?
ii) which cytokine is particularly implicated? what may be seen in blood results? (2)
iii) what happens to the location of haematopoeisis? what is this known as? what does it lead to? what emergency can it lead to?
iv) what gene mutation is usually present? what does it eventually usually transform to?
v) name two treatments

Answer 2

i) can be due to PM, PCV, ET
proliferation of the cell line leads to fibrosis of the bone marrow and it is replaced by scar tissue
ii) release of FGF > see anaemia and low WCC
iii) location of haemato moves to other areas such as liver and spleen > massive splenomegaly = extramedullary haematopoesis
can also lead to portal HTN or spinal cord compression
iv) usually JAK2 +ve (JAK V617F) and usually transforms to AML
v) treat with hydroxycarbamide or JAK inhibtiors

Question 3

POLYCYTHAEMIA VERA
i) how is it defined?
ii) what are the three key signs on examination?
iii) what is first line tx? what can be used to reduce risk of blood clots? what can be used to control the disease

Answer 3

i) raised Hb >185 in men or 165 in women (high Hb and haematocrit)
ii) o/e - conjunctival plethora (red conjunctiva), ruddy complexion, splenomegaly
iii) venesection is first line
aspirin to reduce risk of clots
chemo to control the disease

Question 4

ESSENTIAL THROMBOCYTOPENIA
i) what is found on blood?
ii) what can be used to reduce risk of clots? what can be used to control the disease?

Answer 4

i) plats >600
ii) aspirin
chemo
also use hydroxycarbamide