Which term describes a blood condition characterized by an elevated white blood cell count?

• A. Leukopenia
• B. Anemia
• C. Leukocytosis
• D. Thrombocytopenia

Answer: (C)

A rise in white blood cells signals the immune system is actively responding to infection or inflammation. The term for an elevated white blood cell count is leukocytosis. The word structure helps you see why: leuko- means white, cyt- refers to cells, and -osis indicates an increase or condition. So leukocytosis literally describes a condition of increased white blood cells.

For contrast, leukopenia would mean a low white blood cell count, anemia refers to low red blood cells or hemoglobin, and thrombocytopenia means a low platelet count.