Background Pneumonia is one of the most important disease in childhood and chest X-ray(CXR), the actual standard for diagnosis. Nowadays the lung ultrasound (LUS) is successfully used for diverse pulmonary pathologies in adults. LUS is not irradiant compare to CXR, being suitable for a child investigation. The aim of the study was to evaluate the sensibility of LUS compared to CXR in children with pneumonia.

Methods We designed a prospective study, single–blinded, including 126 children admitted with suspicion of pneumonia. Lung ultrasound was performed using a convex 3–5 MHz probe and a linear 8–12 MHz by a single observer; X-ray was performed afterwards.

Results Pulmonary consolidation was diagnosed in 59 (%) by lung US, in 12.2% associating pleural effusion, compared to chest X-ray, who confirmed the pneumonia in 52 patients. Pleural effusion was found in only 8% by CXR. Another 61 patient had an interstitial syndrome); in this patients a good correlation between LUS and CXR findings was noted(r=0. 77, p<0.001). In majority of patients (71.4%) thoracic US identified alveoli-interstitial signs, confirmed by CXR; in almost all patient radiologist found accentuated lung interstitium, unconfirmed by LUS in 18% of the cases.

Conclusion Lung ultrasound is a reliable method for detection of pneumonia consolidation, with sensibility and specificity surposable with CXR. For the detection of pleural effusions, LUS was superior in terms of sensibility versus CXR. LUS could be used for rapid and safe evaluation in child pneumonia.