277b myeloproliferative neoplasms Flashcards
myeloproliferative disorders
JAK2 is involved in hematopoietic growth factor signaling.
Mutations are implicated in myeloproliferative disorders other than CML.
JAK2 fxn
GF –> JAK P self –> downstream signals via STAT
mutation –> active without GF
CML - mutation?
(no JAK2 mutation)
philadelphia chromosome: bcr-abl transformation –> tyrosine kinase activity –> increased cell division, inhibition of apoptosis
CML -Rx?
Rx imatinib
CML findings -
RBCs
WBCs
Platelets
RBC decreased
WBC increased
platelets increased
Essential thrombocytosis - findings?
increased platelets (little purple dots on smear)
BM have enlarged megakaryocytes that are clustered together
Essential thrombocytosis - what most be excluded?
anything that can cause increased platelet accounts which is more common than ET
post-surgery, splenectomy, infection, etc.
Essential thrombocytosis - clinical presentation?
thrombus –> stroke, PVT, PE
bleeding if ET bad enough
Essential thrombocytosis - mutations
JAK2 or CALR
polycythemia vera - RBC, WBC, Platelets, EPO, mutation
increased x 3 (Hct > 55%) –> suppresses EPO
JAK2 mutation
polycythemia vera - clinical presentation?
gout from increased uric acid
intense itching after a hot shower
erythromelalgia –> severe, burning pain and red color due to episodic blood clot in vessels of extremities
Myelofibrosis - cause?
fibrotic destruction of BM
can arise from ET, PV
Myelofibrosis - smear findings?
leukoerythroblasosis (young WBCs should never see)
tear drop RBCs
Myelofibrosis - BM biopsy?stain?
hypercellularity w/ clustering of abnomral megakaryocytes
stain with reticulin for fibrosis
Myelofibrosis - RBCs? WBCs? platelets?
RBC - decreased –> huge liver and spleen
WBC/Platelets - variable
