From the Guidelines
Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by the overproduction of red blood cells, which can lead to serious complications such as blood clots, heart attacks, or strokes, and should be managed with phlebotomy, low-dose aspirin, and cytoreduction, with either hydroxyurea or interferon at any age, especially in high-risk patients. The disease typically develops slowly, with symptoms including headaches, dizziness, itchy skin (especially after warm baths), fatigue, vision problems, and a reddish or purplish skin color 1. Diagnosis involves blood tests showing elevated red blood cell counts, and often genetic testing for the JAK2 gene mutation, which is present in about 95% of cases.
Key Characteristics of PV
- Overproduction of red blood cells
- Risk of serious complications such as blood clots, heart attacks, or strokes
- Symptoms include headaches, dizziness, itchy skin, fatigue, vision problems, and a reddish or purplish skin color
- Diagnosis involves blood tests and genetic testing for the JAK2 gene mutation
Treatment of PV
- Phlebotomy (blood removal) is the simplest treatment, performed every few months as needed 2
- Medications like hydroxyurea (starting at 500-1000mg daily), ruxolitinib (10-25mg twice daily), or interferon may be prescribed to reduce blood cell production
- Low-dose aspirin (81-100mg daily) is often recommended to prevent clotting
- Lifestyle modifications include staying well-hydrated, avoiding extreme temperatures, and maintaining regular physical activity
Management of High-Risk Patients
- High-risk patients with PV should be managed with phlebotomy, low-dose aspirin, and cytoreduction, with either hydroxyurea or interferon at any age 3
- Monitoring response in PV should use the ELN clinicohematologic criteria
- Corticosteroids, androgens, eryoiesis-stimulating agents, and immunomodulators are recommended to treat anemia of PMF, whereas hydroxyurea is the first-line treatment of PMF-associated splenomegaly.
The disease is chronic but manageable, with proper treatment significantly reducing risks of serious complications. Regular monitoring of blood counts is essential for adjusting treatment as needed 1, 2, 3.
From the Research
Definition and Characteristics of Polycythemia Vera (PV)
- Polycythemia vera (PV) is a Philadelphia negative myeloproliferative neoplasm characterized by erythrocytosis, which is an increased red blood cell mass 4.
- PV is associated with an increased risk of thrombosis, hemorrhage, myelofibrosis, and acute myeloid leukemia 4.
- The major cause of morbidity and mortality in PV is thrombosis 5.
- Erythrocytosis (hemoglobin >16.5 mg/dL in men or >16.0 mg/dL in women) is a required diagnostic criterion for PV 4.
Clinical Features and Diagnosis
- Common clinical features of PV include pruritus, erythromelalgia, transient visual changes, and splenomegaly with abdominal discomfort 4.
- More than 95% of patients with PV have a JAK2 gene variant, which helps distinguish PV from secondary causes of erythrocytosis 4.
- Thrombocytosis and leukocytosis are common in PV, occurring in 53% and 49% of patients, respectively 4.
Treatment and Management
- All patients with PV should receive therapeutic phlebotomy (goal hematocrit, <45%) and low-dose aspirin (if no contraindications) 4.
- Patients who are at higher risk of thrombosis, such as those aged 60 years or older or with a prior thrombosis, may benefit from cytoreductive therapy with hydroxyurea or interferon 4.
- Ruxolitinib, a Janus kinase inhibitor, can alleviate pruritus and decrease splenomegaly in patients who are intolerant of or resistant to hydroxyurea 6, 7, 4.
- Treatment with anagrelide may be limited to situations where patients develop thrombohemorrhagic episodes in the setting of extreme thrombocytosis 7.