Background: Clinical assessment is the gold standard for diagnosis of bronchiolitis. To date, only one study found LUS (Lung Ultrasound) to be a valuable tool in the diagnosis of bronchiolitis. Aim of this study is to evaluate the accuracy of lung ultrasonography in the diagnosis and management of bronchiolitis in infants.
Methods: This was an observational cohort study of infants admitted to our Pediatric Unit with suspected bronchiolitis. A physical examination and lung ultrasound scans were performed on each patient. Diagnosis and grading of bronchiolitis was assessed according to a clinical and a ultrasound score. An exploratory analysis was used to assess correspondence between the lung ultrasound findings and the clinical evaluation and to evaluate the inter-observer concordance between the two different sonographs.
Results: One hundred six infants were studied (average age 71 days). According to our clinical score, 74 infants had mild bronchiolitis, 30 had moderate bronchiolitis and two had severe bronchiolitis. 25 infants composed the control group. Agreement between the clinical and sonographic diagnosis was good (90.6%) with a statistically significant inter-observer ultrasound diagnosis concordance (89.6%). Lung ultrasound permits the identification of infants who are in need of supplementary oxygen with a specificity of 98.7%, a sensitivity of 96.6%, a positive predictive value of 96.6% and a negative predictive value of 98.7%. An aberrant ultrasound lung pattern in posterior chest area was collected in 86% of infants with bronchiolitis. In all patients clinical improvement at discharge was associated with disappearance of the previous LUS findings. Subpleural lung consolidation of 1 cm or more in the posterior area scan and a quantitative classification of interstitial syndrome based on intercostal spaces involved bilaterally, good correlate with bronchiolitis severity and oxygen use.
Conclusions: The lung ultrasound findings strictly correlate with the clinical evaluations in infants with bronchiolitis and permit the identification of infants who are in need of supplementary oxygen with high specificity. Scans of the posterior area are more indicative in ascertaining the severity of bronchiolitis.
Trial registration: Clinical Trial Registration NCT01993797.