Polycythemia vera is a bone marrow neoplasm in which the marrow makes too many red cells, often with extra white cells and platelets, driven in almost all cases by a JAK2 mutation. The thick blood raises the risk of clots such as stroke, heart attack and abdominal vein thrombosis.
Key symptoms
- Headache, dizziness and blurred vision
- Itching after a warm shower or bath
- Burning pain and redness in the hands and feet (erythromelalgia)
- Fatigue, night sweats and abdominal fullness
- Sometimes found by a high hemoglobin on routine labs
What you find on exam
- Red or ruddy face
- Enlarged spleen
- High blood pressure
- Signs of past or current clots: swollen leg or neurologic deficits
Tests
- Blood count: high hemoglobin or hematocrit, often high platelets and white cells
- JAK2 V617F mutation test (exon 12 if negative)
- Low or normal erythropoietin level
- Bone marrow biopsy in some patients; rule out secondary causes such as smoking, sleep apnea and testosterone
Treatment basics
- Phlebotomy to keep the hematocrit under 45 percent
- Low-dose aspirin for most patients
- Hydroxyurea for high-risk patients (age over 60 or past clot)
- Ruxolitinib or interferon in selected patients
- Control heart risk factors and stop smoking
Red flags
- Sudden weakness, trouble speaking or chest pain: stroke or heart attack
- Abdominal pain with ascites: hepatic vein thrombosis (Budd-Chiari)
- Painful, swollen leg or sudden shortness of breath
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.