The white blood cell differential assesses the ability of the body to respond to and fight infection, including HIV-AIDS. It can detect the severity of allergic and drug reactions, parasitic and other types of infection. It can also identify some types of leukaemia and lymphoma, and detect other diseases affecting the bone marrow.
The results indicate the relative percentage and actual numbers of each type of white blood cell that is present.
Neutrophilscan increase in response to bacterial infection, inflammatory disease, steroid medication, or more rarely leukaemia. Decreased neutrophil levels may be the result of severe infection, liver disease, enlarged spleens or other conditions, such as responses to various medications or chemotherapy.
Eosinophils can increase in response to allergic disorders, inflammation of the skin, and parasitic infections. They can also occur in response to some infections or to various bone marrow malignancies.
Basophils can increase in cases of leukaemia, long-standing inflammation, the presence of a hypersensitivity reaction to food, or radiation therapy.
Lymphocytescan increase in cases of bacterial or especially viral infection, leukaemia, lymphoma and in people with underactive or absent spleens. Decreased lymphocyte levels are common in later life but can also be due to steroid medication, stress, lupus, and HIV infection.
Monocytelevels can increase in certain leukaemias, in response to infection of all kinds as well as to inflammatory disorders. Decreased monocyte levels can indicate bone marrow injury or failure and some forms of leukaemia - especially "hairy cell leukaemia" .
This article was last reviewed on 27 October 2010. | This article was last modified on 19 October 2011.
The review date indicates when the article was last reviewed from beginning to end to ensure that it reflects the most current science. A review may not require any modifications to the article, so the two dates may not always agree.
The modified date indicates that one or more changes were made to the article. Such changes may or may not result from a full review of the article, so the two dates may not always agree.