leukocytosis
Last reviewed 01/2018
Leucocytosis is an increase in the number of white blood cells in the blood. It is a common feature of inflammatory reactions, particularly those caused by bacteria. The type of leucocyte increasing in number is dependent on the stimulus type and chronicity; subtypes include:
- neutrophilia
- basophilia
- eosinophilia
- lymphocytosis
- monocytosis
The level of leukocytosis is an insensitive guide to the severity of established infection. Typical values are:
- abscesses: 11-20 * 10^9 per litre
- peritonitis: >20 * 10^9 per litre
- septicaemia: up to 100 * 10^9 per litre - a leukaemoid reaction - or conversely, very low levels
Leukocytosis should be contrasted with leukopenia.