Absolute neutrophil count (ANC) of <500 cells/mm3 or an ANC that is expected to decrease to <500 cells/mm3 during the next 48 h

The term “profound” is sometimes used to describe neutropenia in which the ANC is <100 cells/mm3

The term “functional neutropenia” refers to patients whose hematologic malignancy results in qualitative defects (impaired phagocytosis and killing of pathogens) of circulating neutrophils.
These patients should also be considered to be at increased risk for infection, despite a “normal” neutrophil count