Low white blood cell levels

Leukopenia
Synonyms	leukocytopenia,leucopenia
Classification and external resources
Specialty	Infectious disease, hematology
ICD-10	D70
ICD-9-CM	288.50
DiseasesDB	32396
MeSH	D007970
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Leukopenia is a decrease in the number of white blood cells (leukocytes) found in the blood, which places individuals at increased risk of infection.

Neutropenia, a subtype of leukopenia, 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. This should not be confused with agranulocytosis.

The term is from Greek λευκός "white" and πενία "deficiency".

Low white cell count may be due to acute viral infections, such as a cold or influenza. It can be associated with chemotherapy, radiation therapy, myelofibrosis and aplastic anemia (failure of white cell, red cell and platelet production), stem cell transplant, bone marrow transplant, HIV and AIDS and steroids are also a threat to white cells.

Other causes of low white blood cell count include systemic lupus erythematosus, Hodgkin's lymphoma, some types of cancer, typhoid, malaria, tuberculosis, dengue, rickettsial infections, enlargement of the spleen, folate deficiencies, psittacosis, sepsis, sjogren's disease and Lyme disease. Many other causes exist, such as deficiency in certain minerals, such as copper and zinc.

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