Pertussis: Severe clinical presentation in pediatric intensive care and its relation to outcome*

[[[ Objective: ]]] To describe our institutional experience in the management of infants and children with pertussis admitted during a 20-yr period (January 1985 through December 2004) and also to study the relation between method of presentation and outcome. [[[ Setting: ]]] Pediatric intensive care unit in a university-affiliated tertiary pediatric hospital in Melbourne, Australia. [[[ Design/methods: ]]] Retrospective review of medical records and radiology reports of patients with a diagnosis of pertussis identified from the pediatric intensive care unit database. [[[ Results: ]]] A total of 49 patients (median age, 6 wks; interquartile range, 4-8 wks) required 55 admission episodes to the pediatric intensive care unit. Main reasons for admission were apnea with or without cough paroxysms (63%), pneumonia (18%), and seizures (10%). None of the infants had completed the primary course of immunization, and 94% had not received a single dose of pertussis vaccine. Infants presenting with pneumonia presented earlier (p = .001), had longer intensive care stay (p = .007), higher white cell count (p < or = .001), lower Pao2 at admission (p = .020), and higher mortality. Six infants out of seven needing circulatory support died (including all four treated with extracorporeal membrane oxygenation), and all deaths (n = 7) occurred in infants who had pneumonia at presentation. [[[ Conclusion: ]]] Patients with pertussis, presenting as apnea (with or without cough paroxysms), treated in the pediatric intensive care unit had 100% survival. However, pneumonia as the main reason for admission and the need for circulatory support is associated with a very poor outcome. A deeper understanding of the molecular basis of Bordetella pertussis and its relation to the human host might offer means for future therapies.