Which term describes an increased number of leukocytes in the blood, often due to infection?

Leukocytosis is the term that refers to an increased number of leukocytes, or white blood cells, in the blood. This condition is often a response to various factors, most notably infection. When the body faces an infection, the immune system activates, leading to the production and release of more leukocytes from the bone marrow to combat pathogens. As a result, you will see a significant rise in the white blood cell count, which is an essential marker in diagnosing and monitoring infections.

In contrast, leukopenia describes a decreased number of leukocytes, thrombocytopenia indicates a low platelet count, and anemia refers to a deficiency in red blood cells or hemoglobin, leading to diminished oxygen transport in the blood. Each of these conditions affects blood composition differently, but specifically, leukocytosis is associated with the body’s defense mechanism against infection.