Influenza shows a leucopenia at first, then a leucocytosis and, following the fall in fever, a second lowering. The very fatal pneumonias of the 1918 epidemic of influenza showed a marked leucopenia.
With meningitis counts of 25,000 are not unusual, in abscess of the brain the white count rarely exceeds 15,000.
Poliomyelitis and polioencephalitis give a slight leucocytosis during the febrile accession.
Erysipelas and epidemic cerebro-spinal meningitis also give a leucocytosis of from 15,000 to 20,000. In malignant diseases we sometimes have a moderate leucocytosis. Rogers states that in liver abscess, with a leucocytosis of 15,000 to 20,000 we have only about 75 to 77% of polymorphonuclears—there being also a moderate increase in the percentage of large mononuclears.
Drugs such as antipyrin may give a leucocytosis. The leucocyte increase of pilocarpine is rather a lymphocytosis. Cinnamate of soda, sodium nucleate, bacterin injections and turpentine have been used in kala-azar to increase leucocytes.
Lymphocytosis
Of course, the disease in which we have the most marked lymphocytosis is lymphatic leucaemia.
The lymphocytosis of typhoid fever has been taken up under leucopenia.
Whooping-cough may give a lymphocytosis of 20,000 to 30,000.