From the Guidelines
For a patient with an elevated red blood cell count of 5.39 x 10^12/L, management should focus on determining the underlying cause rather than immediate treatment, as this value is only slightly above the normal range. The first step is to order additional tests including hemoglobin, hematocrit, and red cell indices to assess for polycythemia vera or secondary erythrocytosis, as recommended by guidelines for managing hematologic problems in adults with congenital heart disease 1. Checking oxygen saturation levels and arterial blood gases can help identify if hypoxemia is causing compensatory erythrocytosis. If dehydration is suspected, rehydration with oral or IV fluids should be initiated. According to the acc/aha 2008 guidelines, therapeutic phlebotomy is only indicated for hemoglobin greater than 20 g per dL and hematocrit greater than 65%, associated with headache, increasing fatigue, or other symptoms of hyperviscosity in the absence of dehydration or anemia 1. Regular monitoring of complete blood counts is essential for all patients with elevated RBC counts to track progression and response to interventions. Key considerations include:
- Assessing for underlying causes of erythrocytosis
- Evaluating for signs of hyperviscosity
- Avoiding unnecessary phlebotomies due to the risk of iron depletion and decreased oxygen-carrying capacity 1
- Monitoring for iron deficiency, which can occur even in the presence of erythrocytosis, and managing it appropriately to prevent reduced oxygen-carrying capacity and increased risk of stroke 1.
From the Research
Management of Elevated Red Blood Cell Count
The patient's elevated red blood cell (RBC) count of 5.39 x 10^12/L may be indicative of polycythemia vera (PV), a myeloproliferative neoplasm characterized by an increased red blood cell mass and increased risk of thrombosis 2, 3, 4, 5, 6.
Diagnostic Criteria
The diagnosis of PV is based on the World Health Organization's major diagnostic criteria, which include an elevated hemoglobin or hematocrit level, abnormal results on bone marrow biopsy, and presence of the Janus kinase 2 genetic mutation 3, 4, 5, 6.
Treatment Options
The management of PV involves several treatment options, including:
- Therapeutic phlebotomy to maintain a hematocrit of less than 45% 2, 3, 4, 5, 6
- Low-dose aspirin to reduce the risk of thrombosis 2, 3, 5
- Cytoreductive therapy with hydroxyurea or interferon to lower thrombosis risk and decrease symptoms 2, 3, 5, 6
- Ruxolitinib, a Janus kinase inhibitor, to alleviate pruritus and decrease splenomegaly in patients who are intolerant of or resistant to hydroxyurea 2, 5
Risk Stratification
Patients with PV can be stratified into different risk categories based on their age, thrombosis history, and presence of JAK2 mutation 5.
- High-risk patients (age > 60 years or thrombosis history present) require cytoreductive therapy to reduce the risk of thrombosis 2, 5
- Low-risk patients (absence of both risk factors) may not require cytoreductive therapy 5
Treatment Goals
The main goal of therapy in PV is to prevent thrombohemorrhagic complications and improve quality of life 3, 5, 6.