DefinitionBy Mayo Clinic staff
A high red blood cell count indicates there are too many red blood cells circulating in your bloodstream. Red blood cells (RBCs), also called erythrocytes, are produced in your bone marrow and transport oxygen from your lungs to tissues throughout your body. A high red blood cell count is also called erythrocytosis (uh-rith-roh-sie-TOE-sis).
The threshold for a high red blood cell count is somewhat different from one medical practice to another. A high red blood cell count is generally defined as more than 5.72 million red blood cells per microliter (mcL) of blood for men and 5.03 million per mcL for women. In children, the threshold for high red blood cell count varies with age and sex.
- Lichtman MA, et al. Williams Hematology. 8th ed. New York, N.Y.: The McGraw-Hill Companies; 2010. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=69. Accessed Nov. 6, 2012.
- Polycythemia vera (primary polycythemia). The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/sec11/ch141/ch141d.html#sec11-ch141-ch141d-694. Accessed Nov. 6, 2012.
- What is polycythemia vera? National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/poly/printall-index.html. Accessed Nov. 6, 2012.
- Familial erythrocytosis. Genetic Home Reference. http://ghr.nlm.nih.gov/condition/familial-erythrocytosis. Accessed Nov. 6, 2012.
- Renal cell carcinoma. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/sec17/ch241/ch241f.html?qt=kidney%20cancer&alt=sh. Accessed Nov. 6, 2012.
- Malyszko J, et al. Anemia and erythrocytosis in patients after kidney transplantation. Transplant International. 2012;25:1013.
- CBC with differential, blood. Mayo Medical Laboratories. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/9109. Accessed Nov. 6, 2012.