Objectives: Considering the recurrent exacerbation of children with CF and frequent need for radiation exposure, lung ultrasound (LUS) might be a useful tool for evaluation of pulmonary changes.

Methods: A prospective observational study included 82 CF patients (age between 4 months-24 years) monitored in our center for two years period. Ultrasound was performed every 6 months, using a convex 3-5 MHz probe and supplementary exam when patients were admitted for exacerbations. Specific US marks were used for normal lung and detection of consolidation, interstitial syndrome, pleural effusion, emphysema. CT was used as a gold standard for evaluation of pulmonary structural changes and performed after LUS examinations.

Results: Typical LUS signs for consolidation were found in 8.5% of the patients, in 2 of them with pleural effusion; in this patients a good correlation between US and CT findings was noted(r=0. 79, p< 0.001). The main feature found in LUS were alveoli-interstitial lines, specific for interstitial-alveolar syndrome (42.6%) . Lesions were “age-dependent”, with more severe lesions in older patients. LUS detected saccular bronchiectasis in almost all patients confirmed by CT, however tubular bronchiectasis “escaped” LUS , showing a low LUS/CT correlation ( r=0.14, p< 0.9). Emphysema was detected also easily by M mode examination in 32.8% of patients, predominantly infants and toddlers.

Conclusion: Lung ultrasound is a reliable method for detection of substantial lung alterations in children with CF while for incipient bronchiectasis, CT remain superior. US could be use for rapid and safe evaluation in CF pulmonary exacerbations.