2.1 Patients’ enrollment and data collection
This retrospective study involved hospitalized children with SARS-CoV-2
infection, and they were admitted to the Wuhan Children’s Hospital from
January 28 to February 28, 2020, which was the only designated hospital
for treating COVID-19 patients under 16 years in Wuhan. Children who
contacted with confirmed or suspected COVID-19 cases have undergone
confirmatory SARS-CoV-2 nucleic acid real-time reverse transcription
polymerase chain reaction (RT-PCR) testing. All of the individuals
enrolled in this study were tested positive. The clinical courses and
outcomes were followed up until April 30.
In consideration of the possible
secondary literature and statistical studies that can be performed in
the future,23 it should be noted that part of our
cases had been reported concisely in a previous correspondence paper
about the main clinical, laboratory and radiological
findings.8 This study was approved by the
institutional ethics board of the Wuhan Children’s Hospital (Approval
No. WHCH 2020003).
Data comprised of demographic information, clinical presentation,
medical history and comorbidities, chest computed tomography (CT)
images, laboratory results, treatments (medications and oxygen therapy)
and outcomes were obtained from the medical records system and checked
by two independent researchers. The duration of hospitalization, and the
time of RT-PCR conversion (days from the first positive result to the
first negative result of RT-PCR assays for SARS-CoV-2 nucleic acid),
were also calculated. In particular, the information of previously
diagnosed allergic diseases or related, including allergic rhinitis
(AR), asthma, atopic dermatitis (AD), urticaria, and food/drug allergy,
and known allergens were collected, and reconfirmed by telephone
enquiries.
The severity of COVID-19 was also recorded according to the Chinese
expert consensus on the diagnosis, treatment and prevention of
SARS-CoV-2 infection in children (2nd Version).13Severe cases were identified when meeting one of the following criteria:
(a) shortness of breath with increased respiratory rate (RR) except for
the influence of fever and crying (RR ≥ 60 breaths per minute for those
younger than 2 months, RR ≥ 50 breaths per minute for those aged between
2 and 12 months, RR ≥ 40 breaths per minute for those aged between 1 and
5 years, and RR ≥ 30 breaths per minute for those older than 5 years);
(b) oxygen saturation ≤ 92% at rest; (c) hypoxia with accessory
respiration (groaning, flaring of nares, three concave sign), cyanosis,
and intermittent apnea; (d) disturbance of consciousness with somnolence
and convulsions; (e) food refusal or feeding difficulty, with signs of
dehydration; (f) high-resolution CT showing bilateral or multi-lobe
involvement, with rapid aggressiveness or pleural effusion. Critical
type patients should meet one of the following conditions and admit to
intensive care unit (ICU): (a) respiratory failure with mechanical
ventilation required; (b) shock; (c) complications with other organ
failures. Patients who only had mild symptoms without pneumonia changes
in chest CT images were referred to as the acute upper respiratory
infection (AURI) type, and those who had COVID-19 pneumonia not meeting
the above criteria of severe cases as the mild type. Individuals only
positive for SARS-CoV-2, without any symptoms or changes in chest CT
images were defined as asymptomatic (inapparent) infection.