Cyclic neutropenia

Neutropenia is a haematological disorder characterised by an abnormally low number of neutrophil granulocytes (a type of white blood cell). Neutrophils usually make up 50-70% of circulating white blood cells and serve as the primary defence against infections by destroying bacteria in the blood. Hence, patients with neutropenia are more susceptible to bacterial infections and without prompt medical attention, the condition may become life-threatening. Neutropenia can be acute or chronic depending on the duration of the illness. A patient has chronic neutropenia if the condition lasts for greater than 3 months. It is sometimes used interchangably with the term leukopenia. more...

However, neutropenia is more properly considered a subset of leukopenia as a whole.

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