Limitations
Our study has a number of limitations. First, like all ultrasound
examinations, it is an operator-dependent technique and is associated to
a learning curve. To minimize variability, even though the ultrasounds
were performed by only two emergency pediatricians with lung ultrasound
training, the rescued images were subsequently reviewed by the same
operators (Cohen’s kappa .80). Secondly, the ultrasound aspects
described are not pathognomonic of SARS-CoV-2infection since they are
artifacts also found in the course of other lung diseases (e.g.
bronchiolitis). These ultrasound aspects, in fact, have a fundamental
role for the pediatrician if integrated with the assessment of the child
affected by SARS-CoV-2in the classification of the severity of the
disease and in the programming of other laboratory and instrumental
tests but do not allow the current state of our knowledge to perform
diagnosis of COVID-19.