Evaluation and Management of Erythrocytosis

Initial Assessment

The American College of Cardiology recommends determining if a patient's condition represents true erythrocytosis versus relative erythrocytosis by ensuring adequate hydration status, according to the American Heart Association guidelines 1, 2, 3
Assess for symptoms of hyperviscosity such as headache, visual disturbances, fatigue, or poor concentration in patients with erythrocytosis, as suggested by the American Heart Association 2, 4
Evaluate for potential underlying causes through targeted history and examination focusing on cardiopulmonary symptoms suggesting hypoxemia, as recommended by the American College of Cardiology 1

Assess iron status with serum ferritin and transferrin saturation to evaluate the extent of erythrocytosis, as recommended by the American College of Cardiology 1, 2
Perform peripheral blood smear to evaluate red cell morphology, as suggested by the European Hematology Association 5
Evaluate red cell distribution width (RDW) to assess for underlying pathology affecting erythrocytes, as recommended by the International Society for Laboratory Hematology 6

Ensure adequate hydration as first-line therapy for all patients with erythrocytosis, as recommended by the American Heart Association 2, 3
Avoid routine phlebotomy unless specific indications are present, such as hemoglobin >20 g/dL and hematocrit >65%, or symptoms of hyperviscosity, as suggested by the American College of Cardiology 1, 2, 3, 4
Treat the underlying cause of secondary erythrocytosis, such as hypoxemia or sleep apnea, as recommended by the American College of Cardiology 1
Monitor hemoglobin and hematocrit periodically in patients with secondary erythrocytosis, as suggested by the American College of Cardiology 1
Cautious iron supplementation with close monitoring of hemoglobin levels is recommended for patients with iron deficiency and erythrocytosis, as suggested by the American College of Cardiology 1, 2
Iron deficiency in erythrocytosis can increase stroke risk and should be corrected, as recommended by the American College of Cardiology 1

Avoid routine phlebotomies as they can lead to iron depletion, decreased oxygen-carrying capacity, and increased stroke risk, as warned by the American Heart Association 2, 3
Recognize that iron deficiency can mask the full extent of erythrocytosis while still contributing to symptoms of hyperviscosity, as noted by the American College of Cardiology 1, 2
Monitor renal function as chronic erythrocytosis can affect renal glomeruli and lead to reduced glomerular filtration rate, as recommended by the American Heart Association 2

The Mayo Clinic recommends measuring serum erythropoietin (EPO) level, as it is typically low or low-normal in polycythemia vera, while elevated levels suggest secondary erythrocytosis 7