What is Leucocytosis?
Often during the course of illness, the total number of white blood cells may either increase or decrease. Sometimes this may be dramatic. The term leucocytosis is used when there is an increase of the white cells above the level of normal (usually considered to be around 11.0 per liter, usually written as 11.0 x 109/L by the doctor). Conversely, if the numbers drop to below the normal level (4.0 – 5.0), a condition referred to as leucopenia is said to be present. These figures usually refer to the number of granulated white cells, or neutrophil polymorphonuclear cells.
Leucocytosis commonly follows on from an infection of the body, for this the way in which the system defends itself. By greatly augmenting its fighting forces, the chances of the invading germs being overcome quickly escalate. But there are other conditions in which there may be an increase in white cell counts. These include hemorrhage, trauma (such as accidents or surgical operation), fractures, crash injuries, burns.
It may take place after a heart attack (myocardial infarction, or a clot in the lungs called a pulmonary infarction), in cancers (particularly if the liver is involved), in Hodgkin’s disease, in leukemias and in any of the diseases affecting the blood-production sites. In some cases the counts are very high, and often immature white cells are pumped into the general circulation. Often blood tests will show the occurrence of this phenomenon, and also serial estimations may be used as an indication of the progress of the underlying disorder.
It is important to stop medication with the implicated drug at once, treat any infections, and remove the patient from the environment where infections are likely. In some places it may be possible to have the patient nursed in specialized areas. Specialized treatment for serious cases is essential, and certain drugs may assist. Just as there may be an above- or below-normal number of neutrophil white cells, so the numbers of circulating eosinophils and basophils, the two other types of granulated white cells, may also be affected.
The eosinophil count may increase in many diseases, particularly those associated with allergies. It may therefore be found in asthma, hay fever, drug allergies, serum sickness and urticaria, all of which have a common allergic basis. It may also occur in certain parasitic worm infestations, and some skin disorders such as eczema and pemphigus. It can take place in certain malignant disorders, particularly Hodgkin’s disease and chronic leukemia.
The basophils occur in increased numbers mainly if there is disease of the blood-forming centres, particularly chronic granulocytic leukemia. Occasionally it occurs in certain chronic anemias.
The lymphocytes, another type of white cell produced in lymphoid tissue (spleen and lymph glands of the system), may normally be high in children until the age of 12 years. Increased counts may occur during certain illnesses, particularly whooping cough, viral infections, mumps, measles, chickenpox, viral hepatitis and glandular fever, as well as some bacterial infections.
In adult life the most common cause for high counts is chronic lymphocytic leukemia. Monocytes, also produced in the lymphatic tissue, may increase in numbers during glandular fever and certain leukemias.