Role of lung ultrasound in identifying COVID-19 pneumonia in patients with negative swab during the outbreak

Abstract

Lung ultrasound is a reasonable tool for detection of manifestations of COVID-19, to facilitate the division of patients flow of infected with SARS-CoV-2 from those affected by other pathologies. Often, a reason for the incorrect separation of the flows is the possibility of false-negative rRT-PCR results. We aimed to evaluate the advantages of performing Lung Ultrasound (LUS) in patients with a negative swab, to confirm the suspicious of COVID-19 at the bedside, according to the recent findings of typical lung ultrasound lesions of COVID19 related pneumonia. We analyzed 11 non-critical patients admitted to Emergency Department in the Internal Medicine ward, during outbreak, as Covid-19 negative patients affected by pneumonia. The result of the ultrasound findings conditioned the consequent allocation of the patient. 9/11 patients had typical LUS findings for COVID-19, but only 3/11 patients had a second positive nasopharyngeal swab, and 2/11 had positive swab on pleural fluid. 6/11 patients remained negative with strongly suspicious LUS lesions, and so treated and isolated as Covid-19 positive. 2/11 had negative swab and none LUS findings, thus treated as affected by other pathologies. These findings clearly show how LUS plays an important role together with the chest x-ray in identifying patients with interstitial pneumonia from COVID-19.