Low White Blood Cell Count (leukopenia)

Leukopenia (also known as leukocytopenia, or leucopenia) is a decrease in the number of white blood cells (leukocytes) found in the blood, which places individuals at increased risk of infection.

Neutropenia is a sub-type of leukopenia that refers to a decrease in the number of circulating neutrophil granulocytes, the most abundant white blood cells. The terms leukopenia and neutropenia may occasionally be used interchangeably, as the neutrophil count is the most important indicator of infection risk.