Leukopenia

Leukocytes, commonly known as white blood cells, are a component of blood. There are five main types of leukocytes: neutrophils, eosinophils, basophils, monocytes, and lymphocytes, with neutrophils being the most abundant. Leukocytes primarily function to resist the invasion of pathogens in the human body. The normal total leukocyte count is (4.0 ~ 10.0) × 10^9/L. When the peripheral blood leukocyte count consistently falls below 4.0 × 10^9/L, it is termed leukopenia. Since neutrophils constitute the majority of leukocytes, leukopenia is, in most cases, caused by neutropenia.