What is the approach to polycythemia?

From the Guidelines

The approach to polycythemia involves managing all patients with phlebotomy to maintain the hematocrit at less than 45% and low-dose aspirin 1.

Key Components of Management

• Phlebotomy: to control hematocrit levels
• Low-dose aspirin: to reduce the risk of thrombosis
• Cytoreduction: indicated in high-risk patients, with hydroxyurea or interferon as first-line therapy 1

Indications for Cytoreductive Therapy

• Poor tolerance of phlebotomy or frequent phlebotomy requirement
• Symptomatic or progressive splenomegaly
• Severe disease-related symptoms
• Platelet counts greater than 1,500 × 10^9/L
• Progressive leukocytosis

Additional Considerations

• Risk stratification: to identify patients with a low risk of vascular events 1
• Pregnancy: requires a more aggressive treatment approach, with cytoreductive therapy and strict hematocrit control 1
• Response to treatment: assessed using the ELN criteria, which includes complete remission, partial remission, no response, and progressive disease 1

From the Research

Approach to Polycythemia

The approach to polycythemia involves a standard investigative approach to identify patients with primary and secondary polycythaemia, as well as those with idiopathic erythrocytosis and apparent polycythaemia 2.

Diagnosis and Treatment

• Diagnosis of polycythemia vera (PV) is based on erythrocytosis, thrombocytosis, and leukocytosis, as well as the presence of a JAK2 gene variant 3.
• Treatment of PV involves therapeutic phlebotomy to maintain a hematocrit of less than 45%, as well as low-dose aspirin to reduce the risk of thrombosis 4, 3.
• Cytoreductive therapy with hydroxyurea or interferon may be used in patients at high risk of thrombosis or with persistent symptoms 3.
• Ruxolitinib, a Janus kinase inhibitor, may be used to alleviate pruritus and decrease splenomegaly in patients who are intolerant of or resistant to hydroxyurea 3.

Management of Secondary Polycythemia

• Secondary polycythemia may be caused by chronic hypoxemia, and treatment involves addressing the underlying cause, such as with long-term oxygen therapy or non-invasive ventilation 5.
• Measurement of serum EPO levels and search for JAK2 mutations can guide towards the etiology of polycythemia 6.

Clinical Considerations

• Polycythemia can progress to myelofibrosis or acute leukemia, and management aims to reduce the hematocrit below 45% to limit thrombo-embolic complications 6.
• Patients with polycythemia should be carefully followed up to identify possible causative mechanisms and to monitor for complications 2.