Myeloproliferative disorders Flashcards
Myeloproliferative - definition
Proliferation of myeloid cells within the bone marrow
Myeloid cells within the bone marrow - categories
Granulocytes
Red cells
Platelets
Histology
Mixture of different cell types
Hypercellular
What are the 2 subtypes
BCR-ABL1 negative
BCR-ABL1 positive
Which 3 conditions are BCR-ABL1 negative?
Polycythaemia Rubra Vera
Essential thyombocythaemia
Idiopathic myelofibrosis
What condition is BCR-ABL1 positive?
Chronic myeloid leukaemia
When should you consider MPD as a diagnosis?
When there is NO reactive (secondary) explanation
High granulocyte count +/- High RBC count / Hb +/- High platelet count +/- Eosinophilia/basophilia +/- Splenomegaly
MPD is always a primary problem in the bone marrow itself. True or false?
True
Eosinophilia/basophilia is more likely to indicate primary or secondary problem
Primary (MPD)
If patient has bloods taken and the results are significantly abnormal, what is the course of action?
Re-check the blood count to make sure there haven’t been any errors
Clinical features
Asymptomatic
Increased cell turnover
- gout, fatigue, weight loss, sweats
Symptoms/signs due to splenomegaly
erythromelalgia
Polycythaemia rubra vera - blood count features
High Hb / HCT
Erythrocytosis (too many red cells)
Low EPO levels
May have excessive production of other lineages
Secondary polycythaemia - features
Chronic hypoxia
Smoking
EPO-secreting tumour
Pseudopolycythaemia
Normal amount of RBC but on blood count it appears to be high as it is relative to a reduction in the plasma volume
Polycythaemia rubra vera - clinical features
Common to MPD Headache Fatigue Itch (aquagenic puritis) - worse on exposure to warm water
Patient with an itch that is worse on exposure to warm water has which condition?
Polycythaemia rubra vera
Polycythaemia rubra vera - genetics
JAK2 mutation
- present in over 95% of patients
Polycythaemia rubra vera - mutational analysis forms part of initial screening. True or false?
True
Polycythaemia rubra vera - management
Venesect to haematocrit <0.45 (ie - take pints of blood off)
Aspirin (too many red cells means they are more likely to thrombose)
Cytotoxic oral chemo
Essential thrombocythaemia - definition
Too many platelets
- also, platelets are larger than normal
- platelets are ABNORMAL
Essential thrombocythaemia - clinical features
Common to MPD
Bleeding
Digital ischaemia
Common reactive reason for high platelet count
Churning out platelets to combat the haemostatic challenge they have had with past
Essential thrombocythaemia - investigations
JAK2 mutations (in 50%)
JAK2 mutations are specific to PRV. True or false?
False
Essential thrombocythaemia - if the patient doesn’t have a JAK2 mutation, then what mutation may they have
CALCR mutation
Essential thrombocythaemia - management
Anti-platelets eg aspirin
Cytoreductive therapy to control proliferation
- hydroxycarbomide
- anagrelide
- interferon alpha
myelofibrosis - types
Idiopathic
Post-polycythaemic or
Myelofibrosis - definition
Marrow failure
Scarring in the bone marrow
Extramedullary haematopoiesis
Myelofibrosis - blood film appearance
Leukoerythroblastic
Tear drop shaped RBCs in peripheral blood
Myelofibrosis - clinical features
Marrow failure
- anaemia
- bleeding
- infection
Splenomegaly
- LUQ pain
- complications
Hypercatabolism
Myelofibrosis - what can you do instead of bone marrow aspiration?
Trephine biopsy
Leucoerythroblastic film - causes
Reactive (sepsis)
Marrow infiltration
Myelofibrosis
What is a leucoerythroblastic film composed of?
Myelocytes
Erythroblast (nucleated RBC)
Myelofibrosis - management
Supportive
- blood transfusion
- platelets
- antibiotics
Allogenic stem cell transplantation in select few
Splenectomy
JAK 2 inhibitors
Reactive causes of high counts are more common than MPD. True or false?
True
