[Correlation between ultrasonography and thorax portable radiography in patients with COVID-19]

During the COVID-19 pandemic, portable chest radiography (portable CRx) and lung ultrasonography (LUS) have been widely used to follow up hospitalized patients. Yet, it is scarce the information about the relation between the signs observed by means of each method in patients with COVID-19.

To assess the correlation between concurrent images acquired by LUS and portable CRx during the follow-up of hospitalized patients with COVID-19.

We performed 113 LUS and 113 corresponding CRx during the follow-up of 44 patients (30 men/14 women, 30-85 years old) with COVID-19 (RT-qPCR). Images were stored in a picture communication system and were revised by two specialists of each imaging method independently. Statistical analysis was performed using Gamma correlation and t test (significance level of 0.05).

The most frequent LUS sign was confluent B lines, and it was related to the most frequent portable CRx signs (ground-glass opacities and consolidations). An inverse relationship was observed between A lines (gas in the lungs) and B7 lines (suggestive of interstitial edema). Confluent B lines also showed a strong inverse correlation with A lines (more frequent confluent B lines were related to low frequent A lines), a moderate inverse correlation with B7 lines, and a mild inverse correlation with B3 lines.

During the follow-up of hospitalized patients with COVID-19, LUS and portable CRx may complement each other to provide information about lung damage.