Regional Pulmonary Involvement in Bronchiolitis: Insights From Lung Ultrasound

Acute bronchiolitis is a leading cause of pediatric hospitalization, with severe cases necessitating ventilatory support. Lung ultrasound (LUS) is emerging as a valuable tool for assessing respiratory conditions, yet its utility in evaluating regional heterogeneity in bronchiolitis remains underexplored.

This study aimed to assess the regional distribution of pulmonary lesions in infants with bronchiolitis using LUS and explore their association with the need for ventilatory support.

A prospective study of 160 infants with bronchiolitis was conducted at a tertiary care center. LUS was performed within the first 12 h of admission, with pulmonary regions scored based on the Brat scoring system. Patients were categorized into a favorable outcome group and a ventilatory support group, and the severity of regional lung lesions was analyzed.

Median age was 65.5 days (IQR 38-118.5; range 11-314). Infants requiring ventilatory support exhibited higher regional LUS scores-particularly in lateral-superior, lateral-inferior, posterior-superior, and posterior-inferior zones (p = 0.001); posterior regions showed the highest prevalence of severe lesions. In multivariable analysis, involvement of specific zones independently predicted ventilatory support, notably right lateral-superior (OR 4.6, 95% CI 2.12-9.86), left lateral-superior (OR 3.7, 95% CI 1.78-7.86), left posterior-superior (OR 2.0, 95% CI 1.23-3.51), and left posterior-inferior (OR 2.1, 95% CI 1.20-3.71).

Our findings highlight the heterogeneous distribution of pulmonary involvement in bronchiolitis and underscore the potential role of LUS in severity stratification. However, the study's single-center design necessitates cautious interpretation, with further research needed to validate these results and expand the clinical application of LUS in bronchiolitis management.