Lung ultrasound may support diagnosis and monitoring of COVID-19 pneumonia

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) disease (COVID-19) is characterized by a severe pneumonia and/or acute respiratory distress syndrome (ARDS) in about 20% of infected patients. Computed tomography (CT) is the routine imaging technique for diagnosis and monitoring of COVID-19 pneumonia. Chest CT has high sensitivity for diagnosis of COVID-19, but is not universally available, requires infected or unstable patient to be moved to the Radiology unit with potential exposure of several people, CT room needs proper sanification after use, and is underutilized in children and pregnant women for radioexposition concerns. The increasing frequency of confirmed COVID-19 cases is striking, and new sensitive diagnostic tools are needed to guide clinical practice. Lung ultrasound (LUS) is a non-invasive, bedside and emerging technique for the diagnosis of interstitial lung syndrome by evaluating and quantifying the number of B-lines, pleural irregularities and nodules or consolidations. In patients with COVID-19 pneumonia, LUS shows a typical pattern of diffuse interstitial lung syndrome, characterized by multiple or confluent bilateral B-lines with spared areas, thickening of the pleural line with pleural line irregularity, and peripheral consolidations. LUS showed to be a promising tool for the diagnosis of COVID-19 pneumonia, and LUS findings fairly correlate with chest CT scan. Compared to CT, LUS have several other advantages, such as preventing exposure to radiation, bedside repeatability during follow-up, low-cost and easier application in low-resource settings. Consequently, LUS may decrease utilization of conventional diagnostic imaging resources (CT scan and chest X-ray). LUS may help for early diagnosis, therapeutic decisions and follow-up monitoring of COVID-19 pneumonia, particularly in critical care setting, pregnant women, children and patients in areas with high rates of community transmission.