Myloproliferative Flashcards
What are Myeloproliferative Disorders (MPDs)?
Group of diseases characterized by overproduction of one or more formed elements of the blood without significant dysplasia.
How does WHO classify MPDs?
WHO classifies MPDs into eight disorders.
What is a common feature of MPDs?
Predilection to extramedullary hematopoiesis
Which diseases express primarily a myeloid phenotype?
Chronic myelogenous leukemia (CML)
Which MPDs show erythroid or megakaryocytic hyperplasia?
Polycythemia vera (PV)
What is Polycythemia Vera (PV)?
A clonal disorder involving a multipotent hematopoietic progenitor cell
What is the incidence of PV?
2 per 100
What is the most common cytogenetic abnormality in PV?
Loss of heterozygosity on chromosome 9p due to mitotic recombination.
What mutation is central to the pathogenesis of PV?
JAK2 V617F mutation.
What percentage of PV patients express the JAK2 V617F mutation?
More than 90%.
What are common clinical features of PV?
Splenomegaly
What are some neurologic symptoms of PV?
Vertigo
What is a common vascular complication of PV?
Venous or arterial thrombosis
What is erythromelalgia?
A symptom complex of erythema
What metabolic complications can occur in PV?
Hyperuricemia
How is PV diagnosed?
By elevated hemoglobin
What is a key diagnostic criterion for PV?
Hemoglobin >16.5 g/dL in men or >16 g/dL in women.
What is the treatment goal for PV?
Maintain hemoglobin <14 g/dL in men and <12 g/dL in women to avoid thrombotic complications.
What is the role of phlebotomy in PV treatment?
Reduces hyperviscosity and induces iron deficiency to prevent red cell mass reexpansion.
What is the risk of hydroxyurea in PV treatment?
Risk of leukemogenesis.
What is Primary Myelofibrosis (PMF)?
A clonal disorder of a multipotent hematopoietic progenitor cell
What is the incidence of PMF?
It is the least common chronic MPD.
What are common cytogenetic abnormalities in PMF?
9p
What percentage of PMF patients have the JAK2 V617F mutation?
Approximately 50%.