Leukopenia (or leukocytopenia) is defined as a fall in the number of blood leukocytes to under 4,000 white cells per cubic millimetre of blood. It may only affect the granulocytes (in which case we refer to neutropenia) or the lymphocytes (lymphopenia).
It exposes the patient to a high risk of infection.
Leukopenia is a pathological fall in the number of white cells in the blood. © DR