Ch18 Chronic Myeloproliferative Disorders Part II Flashcards
Characteristics of polycythemia Vera:
Cyanosis, polycythemia, and splenomegaly
Granulocytes and megakaryocytic precursors mildly elevated
Bone marrow fibrosis
RBC levels can be normal or decreased
A chronic abnormality of the hematopoietic stem cell characterized by uncontrolled proliferation of erythroid, granulocytic and megakaryocytic cells defines:
Polycythemia Vera
What is the median age of diagnosis for polycythemia Vera?
60, slightly predominant in men
What is the genetic abnormality found in nearly all PV patients?
JAK2 Exon 12 mutation
What is the JAK2?
A cytoplasmic tyrosine kinase encoded by a gene on the short arm of chromosome 9
What are some symptoms of PV?
Headach Ischemic Hemorrhage stroke Angina Myocardial infraction Cramping pain in leg muscle
What is the most common diagnostic finding in PV?
Elevated hemoglobin and hematocrit, plasma volume
The LAP score is ________ in PV in 97% of cases
Elevated
What is the most common treatment of PV?
Phlebotomy - take 1L of blood out to control symptoms
treat patients with iron to replace lost
A chronic myeloproliferative disorder characterized by marked thrombocytosis associated with abnormal platelet function and increased risk of thrombosis and hemorrhage:
Essential thrombocythemia (ET)
What is the most frequent myeloproliferative disorder?
ET
Diagnostic criteria of ET?
Elevated platelet count
Megakaryocytic hyperplasia in the BM
Absence of significant marrow fibrosis
Normal hematocrit and MCV
The JAK2 gene mutation is found in ______ patients with ET
30-50%
What is the most common clinical complication in ET?
Thrombosis and hemorrhage
The peripheral blood smear of ET patients will show ________ marked thrombocytes
> 600,000/ul
ET has no unique marker therefore it is by nature a diagnosis of:
Exclusion
What is the recommended treatment for ET patients that are asymptotic
Carefully monitoring platelet count
What is the ET treatment recommended for high risk patients?
Drugs can be used - chemotherapy
Need to control hemorrhaging and manifestations of thrombosis
Name a clonal myeoloproliferative disease
IMF
Fibrosis of the BM, extra medullary hematopoiesis involving the liver and spleen, and leukoerthroblastosis in the peripheral blood are characteristic what what myeoloproliferative disorder
IMF
Characterized by the proliferation of mainly granulocytes and megakaryocyte leading to the characteristic finding of BM fibrosis
IMF
IMF occurs mainly in patients of _____ years old
67
IMF originates at the level of:
CD34 hematopoietic stem cell
Splenomegaly is seen in ______ at time of IMF diagnosis
85-99%
Symptoms of IMF include:
Fever
Anorexia
Bone pain
What type of anemia is seen in 50-90% of IMF patients?
Normalcy tic normochromic anemia
What causes significant teardrop poikilocytosis in IMF?
When RBC pass through the marrow, the fibrotic sinusoids of the BM and the spleen
What is the only curative treatment for IMF?
Allogenic stem cell transplantation
What is the origin of MPDs?
Neoplastic transformation of multipotential stem cells
The Philadelphia chromosome involves:
t(9:22)
BCR and c-ABL genes
210-kD protein possessing increased tyrosine kinase activity
What is the predominant abnormal erythrocytes morphology associated with idiopathic myelofibrosis?
Teardrop cells
Which featured of chronic myelogenous leukemia are the most important characteristics that distinguish it from myelofibrosis?
Low LAP score and presence of Ph chromosome
What factors cause fibroblast proliferation?
TGF-B
bFGF
PDGF
What are the lab findings in PV?
Increased hematocrit; increased RBCs; increased granulocytes and platelets
What is the expected erythropoietin value in PV?
Decreased
When us myelosuppression advocated in patients with PV?
When thrombosis-associated risk factors are present
What features help distinguish secondary erythrocytes is and relative erythrocytosis from PV?
Absence of splenomegaly; normal leukocyte, platelet and LAP levels
What is the safest and least expensive treatment for patients with PV?
Therapeutic phlebotomy
What condition is characteristically associated with reactive thrombocytesis?
Acute hemorrhage
Chronic inflammatory disorders
Iron deficiency anemia
Which MDP is associated with the best prognosis?
CML