Polycythemia Vera: Symptoms and Clinical Manifestations
Polycythemia vera presents with a characteristic constellation of microvascular, thrombotic, and constitutional symptoms that directly result from increased blood viscosity and abnormal platelet function.
Microvascular Disturbances
The most common symptom category involves microvascular circulatory disturbances, which occur frequently in polycythemia vera patients:
- Neurological symptoms include headache, light-headedness, transient neurologic disturbances, ocular disturbances, and tinnitus 1, 2
- Transient visual changes occur in approximately 14% of patients 3
- Atypical chest discomfort and paresthesias are commonly reported 1, 2
Erythromelalgia
- Erythromelalgia manifests as a painful, burning sensation of the feet or hands associated with erythema and warmth 1, 2
- This condition occurs in approximately 3-5.3% of polycythemia vera patients 1, 2, 3
- Low-dose aspirin (81 mg/day) is highly effective for treating erythromelalgia 1, 2
Pruritus (Itching)
- Generalized pruritus is documented in 33-48% of patients, making it one of the most common symptoms 1, 2, 3
- The itching is often aquagenic (triggered by water exposure) 1
- Selective serotonin reuptake inhibitors (SSRIs) have shown effectiveness in treating pruritus 1, 2
- Interferon-α is particularly recommended for patients with intractable pruritus 1, 2
Physical Examination Findings
- Splenomegaly is present in approximately 36% of patients and may cause abdominal discomfort 1, 3
- Microcytosis from iron deficiency can occur, particularly in patients undergoing phlebotomy 1
Hematologic Abnormalities
- Erythrocytosis (hemoglobin >16.5 g/dL in men or >16.0 g/dL in women) is the defining feature 3
- Thrombocytosis occurs in approximately 53% of patients 3
- Leukocytosis is present in approximately 49% of cases 3
Thrombotic and Hemorrhagic Complications
- Arterial thrombosis occurs in approximately 16% of patients prior to or at diagnosis 3
- Venous thrombotic events occur in 7% of patients and can involve unusual sites such as splanchnic veins (Budd-Chiari syndrome) 1, 3
- Bleeding risk is increased, especially in patients with extreme thrombocytosis (platelet count ≥1000 × 10⁹/L) who may develop acquired von Willebrand disease 3
Constitutional Symptoms
- Non-specific constitutional symptoms are common and may require treatment 1
- These symptoms can significantly impact quality of life and may warrant cytoreductive therapy even in lower-risk patients 1
Critical Diagnostic Clue
- JAK2 mutation is present in >95% of polycythemia vera cases and is crucial for distinguishing it from secondary causes of erythrocytosis such as tobacco smoking or sleep apnea 2, 3, 4