The causes of hospital-treated acute lower respiratory tract infection in children.

OBJECTIVE

To determine the etiologic agents in children with acute lower respiratory infection.

DESIGN

A survey of a series of patients.

SETTING

General pediatric hospital serving an urban population with and without referrals in Helsinki, Finland.

PARTICIPANTS

135 Finnish children aged 2 months to 15 years (mean, 1.75 years), with clinically defined acute lower respiratory infection (with difficulty of breathing), or found to have fever and a pneumonic infiltrate on chest roentgenogram.

SELECTION PROCEDURES

Consecutive sample on voluntary basis.

INTERVENTIONS

None.

MAIN RESULTS

Of 121 children with adequate samples, an etiologic diagnosis could be established in 84 (70%): 30 (25%) had bacterial, 30 (25%) viral, and 24 (20%) mixed infections. Antibody assays alone identified the agent in 91% of positive cases.

CONCLUSIONS

Bacterial infections are common but generally underestimated in acute lower respiratory infection; serologic methods add significantly to their detection.