Myeloproliferative Disorders Flashcards
What is a myeloproliferative disorder?
Clonal haemopoietic stem cell disorders with an increased production of one or more types of haemopoietic cells – red cells, granulocytes and/or platelets
Myelo= bone marrow lineage
Proliferative= rapid multiplication
How do myeloproliferative disorders differ from acute leukaemia?
Maturation is preserved
How do myeloproliferative disorders differ from CML?
They are BCR-ALB1 negative, whereas CML is positive
What are the 3 types of MPN?
Primary/idiopathic myelofibrosis
Essential thrombocythaemia
Polycythaemia Vera
What is the clinical presentation common to all forms of MPN?
Can be asymptomatic
Fatigue, weight loss, sweats (red flag symptoms)
Splenomegaly signs
Marrow failure
Thrombosis
What is primary/idiopathic myelofibrosis?
Fibrosis of healthy bone marrow -> leads to lack of production of normal cells
What age group does it affect?
Median age 65, but can affect younger patients
What is the underlying cause?
Unknown
But associated with JAK2, CALR, or MPL gene mutations
How does PMF present?
Marrow failure
Bone marrow fibrosis with no cause
Splenomegaly ( and assoc symptoms) due to extramedullary hematopoiesis
Catabolism- night sweats and extreme weight loss
How is PMF investigated?
FBC: Low RBCs, low platelets, low/high WBCs
Film: leukoerythroblastic features- teardrop RBCs
Bone marrow and trephine- dry aspirate and fibrotic trephine
Genetic testing for JAK2, CALR, MLP
How is PMF managed?
Supportive- transfusions, antibiotics
Allogenic stem cells for those who are fit
JAK2 inhibitors eg ruxolitnib
What is Polycythaemia Vera?
High Hb/Haematocrit x inc in red cell mass
What age group does PV it affect?
Median age 65 but can affect any age group
What causes PV?
JAK2 mutation present in over 95% of patients (so probs that)
