Diagnosis and management of pertussis

Abstract

Pertussis is increasing in frequency among children too young to be vaccinated and among adolescents and adults. This increase is due mainly to waning immunity among vaccinated individuals, who become susceptible during adolescence and adulthood and maintain the circulation of Bordetella pertussis. Infants are at highest risk of severe illness requiring hospital admission, complications and death. The clinical presentation in adolescents, adults and vaccinated individuals may be atypical, with paroxysmal cough of short duration or simply a persistent cough. Culture and polymerase chain reaction may be used to identify B. pertussis infection, but their sensitivity is high only in the early phase of the disease. Serologic tests are not standardized for the diagnosis of pertussis, and their clinical application is limited. Erythromycin is still considered in some countries to be the "gold standard" for therapy and prophylaxis; however, azithromycin and clarithromycin seem equally efficacious and are associated with fewer side effects.

Fig. 1: Synergy between pertussis toxin and filamentous hemagglutinin in binding to ciliated respiratory epithelial cells. Bordetella pertussis attach strongly to the ciliated cells with the combined action of other adhesins (e.g., fimbriae and pertactin). Pertussis toxin has the ability to enter the bloodstream and plays an important role in the induction of clinical immunity. Photo: Lianne Friesen and Nicholas Woolridge