Pediatric Pulmonology 48:280–287 (2013) Lung Ultrasound Characteristics of Community-Acquired Pneumonia in Hospitalized Children Vito Antonio Caiulo, MD, 1 * Luna Gargani, MD, 2 Silvana Caiulo, MD, 3 Andrea Fisicaro, MD, 3 Fulvio Moramarco, MD, 1 Giuseppe Latini, MD, 4 Eugenio Picano, MD, PhD, 2 and Giuseppe Mele, MD 5 Summary. Background: The diagnosis of community-acquired pneumonia (CAP) is based mainly on the patient’s medical history and physical examination. However, in severe cases a further evaluation including chest X-ray (CXR) may be necessary. At present, lung ultrasound (LUS) is not included in the diagnostic work-up of pneumonia. Aim: To describe the ultrasono- graphic appearance of CAP at presentation and during the follow-up. Methods: A total of 102 patients with clinical signs and symptoms suggesting pneumonia, who underwent a clinically driven CXR, were evaluated by LUS on the same day. LUS signs of pneumonia included subpleural lung consolidation, B-lines, pleural line abnormalities, and pleural effusion. The diagnostic gold standard was the ex-post diagnosis of pneumonia made by two independent experienced pediatricians on the basis of clinical presentation, CXR and clinical course follow- ing British Thoracic Guidelines recommendations. Results: A final diagnosis of pneumonia was confirmed in 89/102 patients. LUS was positive for the diagnosis of pneumonia in 88/89 patients, whereas CXR was positive in 81/89. Only one patient with normal LUS examination had an abnormal CXR, whereas 8 patients with normal CXR had an abnormal LUS. LUS was able to detect pleural effusion resulting from complicated pneumonia in 16 cases, whereas CXR detected pleural effusion in 3 cases. Conclusions: LUS is a simple and reliable imaging tool, not inferior to CXR in identifying pleuro-pulmonary alterations in children with suspected pneumonia. During the course of the disease, LUS allows a radiation-free follow-up of these abnormalities. Pediatr Pulmonol. 2013; 48:280–287. ß 2012 Wiley Periodicals, Inc. Key words: lung ultrasound; pneumonia; B-lines; chest X-ray. Funding source: none reported. INTRODUCTION In accordance with the British Thoracic Society guidelines, community-acquired pneumonia (CAP) can be clinically defined as the presence of signs and symp- toms of pneumonia (such as fever of >38.58C, cough and respiratory distress) in a previously healthy child, due to an infection which has been acquired outside the hospital. 1 Chest X-ray (CXR) is not recommended to be performed routinely in uncomplicated cases. However, in selected cases, the diagnosis of pneumonia needs to be confirmed with a CXR. The use of ultrasound for the evaluation of the lung is relatively recent. Until a few years ago, the lung was considered off-limits for ultrasound. 2 This concept, only partially true, derives from the fact that in the normal lung, which consists mostly of air, ultrasound waves are almost completely reflected, without being translated into an image. In a normal subject the pleura is the only visible structure, since the high acoustic imped- ance of the air below prevents visualization of the lung parenchyma. In a normal lung, reverberation artifacts, repetitive and parallel to the pleura, called A-lines, are 1 Department of Pediatrics, Perrino Hospital, Brindisi, Italy. 2 Institute of Clinical Physiology, National Research Council of Pisa, Italy. 3 School of Medicine, San Raffaele University, Milan, Italy. 4 Department of Neonatology, Perrino Hospital, Brindisi, Italy. 5 Italian Federation of Pediatricians, Lecce, Italy. Conflict of interest: None. *Correspondence to: Vito Antonio Caiulo, Department of Pediatrics, Perrino Hospital, Piazza Angeli, 3 - 72100 Brindisi, Italy. E-mail: antoniocaiulo@inwind.it Received 12 October 2011; Revised 19 March 2012; Accepted 20 March 2012. DOI 10.1002/ppul.22585 Published online 2 May 2012 in Wiley Online Library (wileyonlinelibrary.com). ß 2012 Wiley Periodicals, Inc.