2.1 Study design and participants
The study was performed in accordance with the Declaration of Helsinki principles and Good Clinical Practice. The study protocol was approved by the Institutional Review Board of Wuhan Children’s Hospital and Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (Wuhan, China). Written informed consent was waived because of the emergence of this infectious disease.
Medical record review was conducted using the institution’s database from January 21st to March 14th 2020 in Wuhan Children’s hospital and Tongji Hospital. In a prior study included only 20 patients in Wuhan children’s hospital, it only described the general clinical and CT features without follow-up, and didn’t include the evaluation of RT-PCR13.
Inclusion criteria were: (a) age <16 Years old, inpatients; (b) positive RT-PCR results of COVID-19; (c) CT in the picture archiving and communication system (PACS) performed. (d) discharged patients only.
Exclusion criteria were: (a) CT scans were performed greater than 1 months; (b) patients with suboptimal image quality for analysis due to breathing motion artifact; (c) unknown date of RT-PCR.
Pharyngeal swab samples of all the pediatric patients in our study were collected, and the SARS-CoV-2 RNA was detected by RT-PCR. RT-PCR kits from Wuhan HUADA biotechnology Co., Ltd, Shanghai Huirui Biotechnology Co., Ltd or Shanghai BioGerm Medical Biotechnology Co., Ltd. These were approved by China Food and Drug Administration for the detection of SARS-CoV-2 nucleic acid.
The discharge criteria were as follows: (1) normal temperature for at least 3 days; (2) significantly improved respiratory symptoms; (3) two consecutive SARS-CoV-2 throat swabs with negative RT-PCR results were performed at least 24 hours apart.