Polycythemia vera
Background
- Chronic myeloproliferative disorder
- Abnormal proliferation is seen in all 3 cell lines
- Typically in elderly
- Can be asymptomatic or symptomatic
- Commonly caused by JAK2 mutation
Clinical Features
- Severe burning pain in the hands or feet accompanied by a reddish or bluish coloration of the skin
- Suspected with any combination of the following: [1]
- Abnormally elevated hemoglobin levels (>18 g/dL in men; 16 g/dL in women)
- Normal oxygen saturation
- Bleeding complications
- Portal vein thrombosis
- Splenomegaly
- Plethora
- Pruritus after bathing
- May develop hyperviscosity syndrome
Differential Diagnosis
Polycythemia (Erythrocytosis)
- Primary polycythemia (myeloproliferative disorders)
- Secondary polycythemia (due to increased EPO)
- Chronic hypoxemia (e.g. COPD, physiologic altitude adaptations or chronic mountain sickness)
- Carboxyhemoglobin (chronic smokers)
- Renal cyst or hydronephrosis
- EPO-secreting tumors (RCC, hepatocellular carcinoma)
- Anabolic steroid abuse
- Abnormal hemoglobins
Evaluation
Workup
- CBC
- Chem 7
- ESR
- EPO decreased
- Bone marrow biopsy sometimes needed
Evaluation[2]
- Criteria 1: All category A
- Criteria 2: First 3 of category A and any 2 of category B
| Category A | Category B |
|---|---|
| Increased RBC Mass (Men >18.5, Women >16.5) | Thrombocytosis (>400,000) |
| Normal SPO2 (>92%) | Leukocytosis (>12,000) |
| Splenomegaly | Leukocyte Alk Phos >100 |
| Vit B12 >900 |
Management
- Phlebotomy with goal hematocrit < 45%[3]
- Patients with severe plethora, with AMS or vascular compromise can be bled vigorously with removal of 500 mL of whole blood rapidly
- Otherwise, gradual phlebotomy of 500-1000 mL over 24 hours is preferred in less emergent cases
- ASA 81mg
- Myelosuppressive agents (hydroxyurea, interferon-α)
- If presenting with hyperviscosity syndrome:
- IVF and phlebotomy
Disposition
See Also
External Links
References
- ↑ http://emedicine.medscape.com/article/205114-differential
- ↑ Tefferi, A, et al. The 2008 World Health Organization classification system for myeloproliferative neoplasms: order out of chaos. Cancer. 2009; 115(17):3842-7,
- ↑ Marchioli R et al. Cardiovascular events and intensity of treatment in polycythemia vera. N Engl J Med. 2013; 368(1):22-33.