The clinical characteristics and prognosis of pertussis among unvaccinated infants in pediatric intensive care unit

Aim: To evaluate the clinical characteristics, risk factors, and prognosis of pertussis in the pediatric intensive care unit. Material and Methods: Patients who were hospitalized in pediatric intensive care unit between January 2017 and January 2019 and diagnosed as having pertussis were retrospectively evaluated. Samples were taken from tracheal aspirate material in intubated patients and nasopharyngeal swabs in the other patients. Samples for Bordetella pertussis were studied using multiplex real-time polymerase chain reaction. Results: Eighteen patients were admitted to our pediatric intensive care unit with a diagnosis of pertussis. Ten patients were female (55.5%), and all patients were unvaccinated. The median age was 40 (range, 38-47.5) days and the median intensive care unit stay was 9 (range, 5-14) days. All patients had respiratory distress, 14 patients had cough (77.7%), four patients had fever (22.2%), and three patients had convulsions (16.6%). Seven patients were intubated. Three patients died of multiple organ failure and cardiogenic shock despite extracorporeal treatment. Respiratory syncytial virus was found in two patients and rhinovirus was found in one patient. The median leukocyte count was significantly higher in non-survivors than in survivors. Blood exchange was performed in three patients due to hyperleukocytosis. Pulmonary hypertension was the most common cardiac pathology detected in echocardiographic examinations. Conclusion: We found that high leukocyte count, viral co-infection, and severe pulmonary hypertension were associated with mortality and morbidity in pertussis.