Pertussis leukocytosis: mechanisms, clinical relevance and treatment

Pathog Dis. 2016 Oct;74(7):ftw087. doi: 10.1093/femspd/ftw087. Epub 2016 Sep 7.


The significant and sometimes dramatic rise in the number of circulating white blood cells (leukocytosis) in infants suffering from pertussis (whooping cough) has been recognized for over a century. Although pertussis is a disease that afflicts people of all ages, it can be particularly severe in young infants, and these are the individuals in whom leukocytosis is most pronounced. Very high levels of leukocytosis are associated with poor outcome in infants hospitalized with pertussis and modern treatments are often aimed at reducing the number of leukocytes. Pertussis leukocytosis is caused by pertussis toxin, a soluble protein toxin released by Bordetella pertussis during infection, but the exact mechanisms by which this occurs are still unclear. In this minireview, I discuss the history of clinical and experimental findings on pertussis leukocytosis, possible contributing mechanisms causing this condition and treatments aimed at reducing leukocytosis in hospitalized infants. Since recent studies have detailed significant associations between specific levels of pertussis leukocytosis and fatal outcome, this is a timely review that may stimulate new thinking on how to understand and combat this problem.

Keywords: Bordetella pertussis; leukocytosis; lymphocytosis; pertussis toxin.

Publication types

  • Historical Article
  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Antibodies, Monoclonal / therapeutic use*
  • Bordetella pertussis / drug effects
  • Bordetella pertussis / pathogenicity
  • Bordetella pertussis / physiology
  • Exchange Transfusion, Whole Blood / methods*
  • Extracorporeal Membrane Oxygenation / methods*
  • History, 19th Century
  • History, 20th Century
  • History, 21st Century
  • Host-Pathogen Interactions / drug effects
  • Humans
  • Infant
  • Leukocytes / drug effects
  • Leukocytes / microbiology
  • Leukocytes / pathology
  • Leukocytosis / history
  • Leukocytosis / mortality
  • Leukocytosis / pathology
  • Leukocytosis / therapy*
  • Lymph Nodes / drug effects
  • Lymph Nodes / microbiology
  • Lymph Nodes / pathology
  • Pertussis Toxin / antagonists & inhibitors*
  • Pertussis Toxin / metabolism
  • Survival Analysis
  • Whooping Cough / history
  • Whooping Cough / mortality
  • Whooping Cough / pathology
  • Whooping Cough / therapy*


  • Antibodies, Monoclonal
  • Pertussis Toxin