An increased number of red blood cells (RBCs) is called polycythemia or erythrocytosis. This condition results in a higher than normal concentration of red blood cells in the blood, making the blood thicker than usual. This increased RBC mass is reflected by elevated hemoglobin levels and hematocrit, exceeding the physiological norm for a person's age and gender.
Several sources confirm this:
- Cleveland Clinic: States that a high red blood cell count is called erythrocytosis. https://my.clevelandclinic.org/health/symptoms/17810-high-red-blood-cell-count
- Mayo Clinic: While discussing the causes of a high red blood cell count, implicitly supports the terms erythrocytosis and polycythemia as applicable. https://www.mayoclinic.org/symptoms/high-red-blood-cell-count/basics/definition/sym-20050858
- NHS (National Health Service): Directly defines erythrocytosis (also called polycythemia) as a high concentration of red blood cells, resulting in thicker blood. https://www.nhs.uk/conditions/erythrocytosis/
- Medical News Today: Explains that overproduction of RBCs is known as primary polycythemia. https://www.medicalnewstoday.com/articles/what-causes-a-high-red-blood-cell-count
- Rare Diseases: Clearly states that polycythemia vera leads to an increase in red blood cells, resulting in thickened blood (hyperviscosity). https://rarediseases.org/rare-diseases/polycythemia-vera/
- nidirect: Reinforces the interchangeable use of polycythemia and erythrocytosis to describe the condition of increased red blood cell concentration. https://www.nidirect.gov.uk/conditions/polycythaemia
The increased blood thickness associated with polycythemia/erythrocytosis is due to the elevated concentration of red blood cells in the plasma. This increased viscosity can lead to various health complications.
