Myeloproliferative Myelodysplastic Syndromes Flashcards
myeloproliferative and myelodysplastic syndromes deal with
disorders of clonal stem lines of all three linages platelet, WBC, and RBC are affected
three types of myeloproliferative syndromes
- polycythemia vera
- essential thrombosis
- myelofibrosis
erythrocytosis
increased RBC volume, increased hemoglobin and hematocrit
polycythemia
synonym for erythorocytosis
Secondary factors can cause erythrocytosis
these condition tend to lead to erythrocytosis because tissue hypoxia induces EPO to be secrete form the kidneys
- OSA
- obesity causing hyperventilation
- high attitudes
- high affinity hemoglobin
- cardiopulmonary disorders
- high carboxyhemoglobin levels
- tumor
- treatment with androgens or EPO
- rare genetic disorders
erythrocytosis can lead to _______
hyperviscosity
hyperviscosity symptoms
thickening of the blood; headache, tinnitus, decreased mental functioning, dizziness, visual changes, paresthesias
how to treat hyperviscosity?
phlebotomy
polycythemia vera clinical characteristics
erythromelalgia pruritis hypermetabolic state thrombosis - Budd Chiari syndrome Hemorrhage splenomegaly hepatomegaly facial plethora
Budd Chiari syndrome can develop from what two disorders?
polycythemia vera and PNH
phases of polycythemia vera
- latent- asymptomatic
- proliferative- hypermetabolic and hyperviscosity
- spent- anemia, leukopenia, increasing liver and spleen size, fever, weight loss, secondary myelofibrosis
- AML
What mutation is common in patient’s with polycythemia vera?
JAK2
Lab findings for polycythemia
- increased hemoglobin hematocrit
- increased platelets
- increased EPO
- positive for JAK2 mutation
- BASOPHILIA - increased basophils present
- increased uric acid –> can lead to gout
how does polycythemia usually arise?
from a single neoplastic stem cell, mutations in JAK2
treatment for polycythemia?
- phlebotomy
- low dose aspirin
- hydroxyurea
90% of patients with essential thrombocytosis have
somatic genetic mutation
ex. JAK2, CALR, MPL
essential thrombocytosis similar symptoms to p vera except there is increased risk of
arterial or venous thrombosis
essential thrombocytosis clinical symptoms
- pruritis
- erythromelagia
- thrombosis
- hemorrhage
differences compared to p vera
1. digital ischemia
2. no facial plethora
first step in diagnosing essential thrombocytosis
- rule out other causes of thrombocytosis
- order a ferritin level
1. infection
2. cancer
3. iron deficiency
4. bleeding
5. inflammation
who do we treat for essential thrombocytosis?
- patients who are greater than 65
- have greater than 450 platelets on two occasions 1 month apart
- increased risk of thrombosis
treatment is focused on
- decreasing platelet count
- hydroxyurea
laboratory findings for essential thrombocytosis
- JAK2 mutation
- abnormal irregular platelet, usually giant sized
- increased megokaryocytes
- ferritin level should be normal
between the three myeloproliferative disorders which one has the most risk to turn into AML?
myelofibrosis then polycythemia vera then essential thrombocytosis
myelofibrosis is mainly a disorder that
arises from a disorder that affects the clonal stem line for megakaryocytes
treatment for myelofibrosis
- there is not definitive treatment
- supportive care
- splenomegaly to relieve abdominal pain but increased risk of hemorrhage
- if young bone marrow transplant
clinical features of myelofibrosis
- splenomegaly and heptamegoly
- fever, chills, weight loss
- extramedullary hematopoesis that causes splenomegaly which can lead to early satiation
laboratory findings of myelofibrosis
- blood smear- teardrops, NRBC, and granulocytes, leukoerythroblastic (immature leukocytes)
- dry bone marrow tap
- early on the RBC, WBC and Hb are all elevated but as the disease progresses they will all decrease
all myeloproliferative disorders can result in spent phase which is
similar to myelofibosis
myeloid metaplasia
refers to the early proliferative phase of myelofibrosis where there is extrameduallary hematopoiesis
myelodysplastic syndrome
- abnormal clonal line that results in cytopenia
myelodysplastic syndrome is usually found in the
elderly population due to lower levels on CBC
peripheral smear for myeldysplastic syndrome should show
- bilobed neutrophils
- monocytosis- increased number of monocytes
- macrocytosis - with normal levels of B12 and folate
bone marrow biopsy should show
- ringed sideroblast
- megaloblastic erythropoiesis
- blast cells should account for less than 20 % of slide (more than 20 would be leukemia)
- dyserythropoiesis- abnormal nucleus on RBC
- small megokaryocytes with abnormally hypolobated nuclei
mylodysplastic is usually are result of
cytogenetic abnormalities
mylodysplastic treatment
- treatment is usually supportive
- platelet and rbc transfusion
- hypermethylation of DNA
- growth factors
once the patient develops AML
the chances of achieving remission is much shorter
