Introduction
Initially described in China, the severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) virus, etiological agent of the Coronavirus
Disease 2019 (COVID-19), rapidly spread all over the world being
declared a pandemic by the World Health Organization on March
11th, 2020. Although SARS-CoV-2 caused millions of
infections and thousands of deaths struggling all health systems
worldwide, the impact on children has been relatively milder, with a
minority of severe cases and a small number of deaths
reported.1 Despite a relatively mild acute COVID-19 in
children, the Chinese approach included the routine use of chest
Computed Tomography (CT) to all children with SARS-CoV-2 infection no
matter the clinical situation.2 However, many studies
have proposed a clinically based classification of disease severity for
pediatric COVID-19, limiting the use of CT scan to children with severe
disease.3-5 The routine use of CT scan to asymptomatic
or paucysymptomatic patients can bear risks related to radiation
exposure and above all can determine the increase the risk of virus
diffusion due to patient displacement from visit room to X-ray room when
is in hospital or moving the patient from home to hospital after the
discharge.6,7 In this context, lung ultrasound (LUS)
can be a useful tool to evaluate lung involvement in children with
SARS-CoV-2 infection, since COVID-19 is characterized by peripheral lung
lesions easily detected by LUS.8 However, while the
role of LUS in adults with COVID-19 has been widely described and a
prognostic role has been documented, its use in children is not yet
established.9-12 To date, only two small preliminary
case series of Italian children with COVID-19 have been published, while
the role of LUS in the clinical follow-up of children with COVID-19 and
potential implication on the use of CT scan is not yet
defined.13,14 For these reasons, we performed a
prospective observational study in a pediatric COVID-19 hospital aiming
to better clarify the usefulness of LUS in children with COVID-19.