99 - Polycythemia Vera Flashcards
What are the two groups of chronic myeloproliferative diseases?
- Myeloid phenotype
2. Megakaryocyte/erythroid hyperplasia
What are the three myeloid phenotype causing myeloproliferative diseases?
- CML (myelocytic- BCR-ABL)
- CNL (neutrophilic)
- CEL (eosinophilic)
What are the three Megakaryocyte/erythroid hyperplasia causing myeloproliferative diseases?
- PV (polycythemia vera)
- ET (essential thrombocytosis)
- PMF (primary myelofibrosis)
PV frequency increases with ____, it has a slight ____ tendency, with ____ being more prominent in sporadic cases
Age
Familial
Female
In ___ of patients we can find known chromosomal mutations such as ____ deletion or ____
30%
13q or 20q
9 trisomy
In ___ we can find ____ mutation where____ replaces ____
95%
JAK2
Phenylalanine
Valine
The mutation in JAK2 activates it without ___ dependency leading to an uncontrolled cell productio
EPO
Clinical features of PV include: (4)
Leukocytosis/Thrombocytosis
Splenomegaly
Thrombus (venous/arterial)
Aquagenic pruritus
Hypervascular erythrocytosis may lead to the following symptoms: (2)
- Systolic HTN
2. Neurological symptoms (vertigo, headache, visual impairment, TIA, tinnitus)
Thrombocytosis may lead to the following symptoms: (4)
- Thrombosis (cerebral, GI, hepatic vein)
- Acquired vWF
- Erythromelalgia
- Bleeding disorders (fingers ischemia, etc..)
What is the approach to diagnosing patients with PV?
*Increased hct/Hgb?
yes? continue
- Measure RBC mass
normal- Relative erythrocytosis
elevated- continue
*Measure serum EPO levels-
low- PV- confirm with JAK2 mutation
elevated- continue
*Measure arterial O2 saturation
low- DD (COPD, high altitude, AV shunt…)
normal? continue
*Smoker?
no?- measure hemoglobin affinity-
increased- O2 affinity hemoglobinopathy
normal- search for tumors (renal US/CT)
yes?- Measure carboxyhemoglobin
elevated? Smokers polycythemia
In order to confirm absolute erythrocytosis by measuring _____. When unavailable and O2 saturation is normal- check for ____
RBC mass
JAK2 mutation
Normal EPO does not disclose ___, but high EPO suggests ____
PV
Secondary erythrocytosis
What are the 3 situations leading to microcytic erythrocytosis (check RDW and MCV)?
- Beta thalassemia (normal RDW)
- Hypoxic erythrocytosis ( wide RDW)
- PV (wide RDW due to iron deficiency)
___ examination has no value when trying to diagnose PV
BM
The lack of ____ does not rule out PV
genetic marker
What are the two mechanisms leading to PV complications?
Hyperviscosity- due to increased amount of cells
Increased cell turnover- increase in cytokines and uric acid
_____ infection is more common in PV patients, which may lead to higher frequency of ____
H. Pylori
PUD
Men with PV should aim for Hgb of ___ and hct of ___, in order to avoid thrombosis.
<14
<45%
Women with PV should aim for Hgb of ___ and hct of ___, in order to avoid thrombosis.
<12
< 42%
What are the 3 main treatments of PV?
- Phlebotomy
- Anticoagulation
- Ruxolitinib
In PV patients, phlebotomy is recommended once every ___ months
3
If treating PV with anticoagulation, we must avoid ____ when ____ is not under control
Salicylates
RBC
Ruxolitinib is ____, and is used in PV patients who also suffer from ___ or ____.
JAK2 inhibitor
Myelofibrosis
Myeloid metaplasia
