Doctor's Notes on High Red Blood Cell Count (Polycythemia Vera) Symptoms, Causes, and Treatment
Polycythemia refers to an elevated number of red blood cells (termed erythrocytes) in the circulation. This can occur either as a primary condition in which the bone marrow produces too many red blood cells (called polycythemia vera) or it may occur as a reaction to other diseases and conditions (such as hypoxia or low oxygen levels due to any reason) that drive the body to produce an increased number of red blood cells.
Symptoms and signs of polycythemia can be non-specific and may include weakness, fatigue, easy bruising, headache, joint pain, and dizziness. Other associated signs and symptoms can include itching, problems with blood clotting, bleeding, cough, or poor exercise tolerance. The particular signs and symptoms depend on the reason for the elevated red blood cell count.
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See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.