Clinical characteristics of parainfluenza virus infection in hospitalized children.

Severity of illness and clinical characteristics of parainfluenza virus (PIV) infection were evaluated in 81 hospitalized children over a 4 year period. Fifty three patients were previously healthy and 28 had preexisting pulmonary abnormalities associated with bronchopulmonary dysplasia (BPD), congenital heart disease (CHD), asthma, or prematurity. When compared with formerly healthy children, the patients with preexisting pulmonary abnormalities were more likely to develop lower than upper respiratory tract illness (P less than 0.0001). In the lower respiratory tract infection group, patients with preexisting pulmonary abnormalities were sicker (P = 0.047), were hospitalized longer (P = 0.016), required more supplemental oxygen (P = 0.004), and were older (8.8 vs. 5.1 months) than previously healthy patients. Nosocomial infection occurred only in BPD patients. All these patients developed pneumonia. They were sicker (P = 0.0018), requiring more therapy (P = 0.0038) than other patients with preexisting pulmonary abnormalities and lower respiratory tract disease. Patients with BPD should be placed in protective isolation during PIV epidemics.