Clinical and radiographic assessment of acute lower respiratory tract disease in infants and children.

The admission chest roentgenogram, temperature, and WBC of over 100 children with viral lower respiratory disease were compared with those for children with proven bacterial pneumonia. A scoring system was developed to assess the likelihood of bacterial or viral etiology of lower respiratory tract disease. Pulmonary infiltrates that were well defined and involved the mid or peripheral portions of only one lobe, pleural effusions and abscess or pneumatocele formation--characteristics associated with bacterial infection--were assigned a plus score. Poorly defined infiltrates, often involving the perihilar region of more than one lobe, and atelectasis involving the right middle lobe, the right upper lobe or multiple sites--characteristics associated with viral infection--were assigned a negative score. Additional plus scores were given for age greater than 6 months, fever greater than or equal to 103 degrees F, and for an elevated WBC. Application of the scoring system, retrospectively, to cases with proven etiology, demonstrated that a score of 0 or less had a predictive value of 95% for viral pneumonia, while the predictive value of a positive score for bacterial etiology was 70%. Use of the score for initiating antibiotics would have resulted in overtreatment with antibiotics of 11% of the cases. It is recognized that viral infection may facilitate bacterial invasion and that a child may present at any stage during this process; therefore, continuing evaluation and reassessment are important in the management of acute lower respiratory disease. However, the scoring system provides useful guidelines for use of antibiotics in initial treatment of childhood pneumonias, which should reduce unnecessary administration for viral infections.