A low white blood cell count can occur in anyone. The number of white blood cells in the body can vary, depending on a person’s age, race, and gender, and if he or she has certain medical conditions.
Pathogenic cause
A low white blood cell count is associated with certain conditions, including:
Cancer (caused by chemotherapy treatments)
Bone marrow disorders or damage
Autoimmune disorders (problems with the immune system in which the body attacks itself), such as lupus
Infections (including tuberculosis and
HIV)
Immune system conditions
Crohn’s disease
Malnutrition
Radiation treatments for cancer
Rheumatoid arthritis
Vitamin deficiencies