Lung Ultrasound as Good as Chest X-Ray for COVID-19 Diagnosis and Management

A retrospective multicenter study by researchers from Italy, Portugal and Spain has found lung ultrasound (LUS) to be as good as chest X-ray (CXR) for accurate COVID-19 diagnosis.

LUS holds the promise of an accurate, radiation-free, and affordable diagnostic and monitoring tool in coronavirus disease 2019 (COVID-19) pneumonia. The researchers sought to evaluate the usefulness of LUS in the diagnosis of patients with respiratory distress and suspicion of interstitial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, in comparison to other imaging modalities.

In the study, study, LUS was performed on Emergency Department (ED) arrival of patients presenting for possible COVID-19 evaluation, by trained emergency physicians, before undergoing conventional radiologic examination or while waiting for the report. Scans were performed using longitudinal transducer orientation of the lung regions. CXR was interpreted by radiologists staffing ED radiology. The subjects were divided into two groups based on molecular test results. The LUS findings were compared to COVID test results, non-laboratory data, and other imaging for each patient. Categorical variables were expressed as percentages and continuous variables as median ± standard error.

A total of 479 patients were enrolled, out of which 87% were diagnosed with SARS-CoV-2 by molecular testing. COVID positive and COVID negative patients differed with respect to sex, presence of fever, and white blood cells count. The most common findings on lung point of care ultrasound (POCUS) for COVID-positive patients were B-lines, irregular pleural lines, and small consolidation. Normal CXR was found in 17.89% of cases. The study found LUS to be non-inferior to CXR for diagnostic accuracy and COVID-positive patients were most likely to show B lines and sub-pleural consolidations on LUS examination.