3 | RESULTS
We identified only fifteen studies to date using LUS to diagnose SARS-CoV-2 infection in children and these studies involved a total of 334 newborns and children. These studies used LUS and nasal swabs to diagnose SARS-CoV-2 and show the distribution of different ultrasonic patterns as follows: the presence of B-lines in 73.94% of patients, sub-pleural consolidation in 63.44%, pleural irregularities in29.03%, coalescent B-lines in 27.64% and white lung in11.89% and thickening of the pleuralion in 63.52%. Table1 shows the characteristics of included studies.
Regarding the use of CXR and lung US in pediatric patients with COVID-19 infection, we identified six studies with a total of 126 participants, with the following results: 33patients(14.11%) with lung abnormalities on lung US had a normal CXR; however, no patients with normal lung US had abnormalities on the CXR. Regarding the use of CT and lung US in pediatric patients with COVID-19 infection, we identified five studies with a total of 50 participants, with the following results: 3 patients(6%) with lung abnormalities on chest LUS had a normal CT.
Three studies evaluated the relationship between LUS scores and severity of the disease, and only one study demonstrated the application of LUS in follow-up after discharge on COVID-19 children.