What condition is indicated by a decreased number of white blood cells?

Leucopenia is the condition characterized by a decreased number of white blood cells (WBCs). White blood cells are crucial for the immune system as they help the body fight infections and other diseases. When the count of these cells is low, individuals may be more susceptible to infections and may experience symptoms such as fatigue, fever, and increased risk of illness.

Leucopenia can result from various factors, including bone marrow disorders, autoimmune diseases, certain medications, and severe infections. Understanding leucopenia is important for diagnosing and managing conditions that compromise the immune system, making it a critical concept in pathology.

While other options relate to blood cell counts and conditions, they do not specifically describe a decrease in white blood cells. For instance, leukocytosis refers to an increase in white blood cells, anemia pertains to a decrease in red blood cells, and leukemia is a type of cancer that typically leads to elevated white blood cell counts, although it can also cause issues with normal blood cell production. Thus, leucopenia clearly defines the condition of having fewer white blood cells.