What is an abnormal excess of erythrocytes (RBCs) resulting in an increase in blood viscosity called?

The condition characterized by an abnormal excess of erythrocytes (red blood cells) leading to an increase in blood viscosity is known as polycythemia. This occurs when the body produces too many red blood cells, which can strain the cardiovascular system and increase the risk of thrombosis, or blood clots, due to the thicker nature of the blood.

Polycythemia can be primary, stemming from inherent problems in the bone marrow that increase red blood cell production, or secondary, which often results from external factors such as chronic hypoxia or certain tumors producing erythropoietin, the hormone that stimulates red blood cell production. Recognizing this condition is crucial as it can have significant implications for an individual’s health, including increased blood pressure and potential complications related to circulation.

The other conditions mentioned do not relate to an excess of red blood cells; anemia refers to a deficiency of red blood cells, leukemia involves abnormal white blood cells, and hemolysis is the destruction of red blood cells rather than an increase in their number.