Myeloproliferative Disorders Flashcards
What is the disease called when too many RBCs are produced?
Polycethemia Vera
- Type of Myeloproliferative disorder (granulocytes and platelets are also increased)
What is a proliferation of mature lymphoid cells (e.g Naive B cells, CD8or4 T cells) called?
CLL
What is a neoplastic proliferation of mature myeloid cells called?
Myeloproliferative disorders
What is a proliferation of granulocytes called? (type of myeloproliferative disorder)
CML (chronic myelogenous leukemia)
What is a proliferation of the megakaryocytes called?
Essential thrombocytopenia
What is a myeodysplastic syndrome result in?
- High WBC count with hypercellular bone marrow
- All cells of myeloid lineage are increased but classified based on dominant myeloid cell produced
What are the complications of myelodysplastic syndrome?
- Increased risk of hyperuricemia (gout)
- Progression to marrow fibrosis
- Transformation to acute leukemia
What is seen on blood smear in CML?
Increase in granulocytes
- Possible early precursor granulocytes
What does 9;22 translocation result in?
- BCR-ABL fusion resulting in increased tyrosin kinase activity
What is the first line treatment of CML?
Imatinib
- Blocks tyrosine kinase activity
What are the 3 phases of CML?
Chronic, accelerated and transformation phase
What does splenomegaly suggest in CML?
Accelerated phase of disease
- Transformation to acute leukemia follows therafter
What does transformation of CML result in?
AML (2/3) or ALL (1/3)
- Mutation is in a pluripotent stem cell
How do you differentiate between CML and leukemoid reaction (e.g infection)?
- CML granulocytes are LAP negative
- CML is associated with increased basophils
- CML granulocytes exhibit t(9;22)
What mutation is associated with polycythemia Vera?
JAK2 kinase mutation
What are the clinical symptoms of polycythemia Vera?
- Blurry vision and headache
- Increased risk of venous thrombosis
- FLushed face due to congestion
- Itching after bathing (Mast cells release hsitamine)
What is the most common cause of Budd-chiari syndrome?
Polycythemia Vera
What is the treatment of Polycythemia Vera?
- Phlebotomy
- 2nd line treatment is hydroxyurea
- W/o treatment death occurs usually within 1 year
How do you differentiate between Polycythemia Vera (PV) and reactive polycythemia?
- In PV SaO2 is normal (unlike in lung disease where it is decreased)
- PV has decreased EPO (unlike in ectopic EPO production)
Essential Thrombocytopenia
- Neoplastic proliferation of mature myeloid cells, especiallt platelets (many on blood smear)
- RBCs and granulocytes also increased
- Associated with JAK2 kinase mutation
What other disease may have a lot of platelets on blood smear (not essential thrombocytopenia)?
Iron deficiency anemia
What are the symptoms of essential thrombocytopenia?
- Increased risk of bleeding (defective) and/or thrombosis
- Rarely progress to marrow fibrosis or acute leukemia
- No significant risk for hyperuricemia or gout
What is myelofibrosis?
- Neoplastic proliferation of mature myeloid cells, especially megakaryocytes
- Associated ith JAK2 kinase mutation
- Results in marrow fibrosis (due to excess PDGF)
What does marrow fibrosis look like on hsitology?
Pink collagen deposited in marrow space
- due to excess PDGF
What are the clinical features of myelofibrosis?
- Splenomegaly due to extramedullary hematpoiesis
- Leukoerythroblastic smear
- Increased risk of infection, thrombosis and bleeding
What are reticulin gates?
Prohibit immature (larger) cells from exiting into blood - Defective in myelofibrosis (leukoerythroblastic)
What kind of cells may be seen on blood smear in myelofibrosis?
Teardrop cells
