What does leukocytosis refer to?

Leukocytosis refers to a condition characterized by an increase in the number of white blood cells (WBCs) in the bloodstream. Specifically, it is defined as having a white blood cell count greater than 10,000 cells per microliter (mm³) of blood. This increase can be a physiological response to various factors such as infections, inflammation, stress, or even certain medical conditions like leukemia.

The role of white blood cells is crucial in the immune response, as they help the body fight off infections and other diseases. Thus, when the body detects an issue that requires an enhanced immune response, the bone marrow may ramp up the production of white blood cells, resulting in leukocytosis.

The other definitions do not pertain to leukocytosis. A decrease in white blood cells refers to leukopenia, while an increase in red blood cells points to conditions like polycythemia, which is unrelated to white blood cells. A constant number of white blood cells would imply normalcy rather than a change in their levels.