Procedures
Clinical characteristics and outcomes data were obtained with standardized data collection forms from patients’ medical records. Information recorded included demographic data, medical history, underlying comorbidities, symptoms, laboratory findings, chest computed tomographic (CT) scans, treatment measures and outcomes. The durations from onset of COVID-19 to hospital admission were recorded. The data were reviewed by a trained team of physicians. Acute kidney injury was identified according to the Kidney Disease: Improving Global Outcomes definition3. Acute liver injury, defined as either alanine aminotransferase or aspartate aminotransferase greater than three times the upper limit of normal4. Acute respiratory distress syndrome (ARDS) was diagnosed according to the Berlin Definition5.
Laboratory confirmation of SARS-CoV-2 infection was done at Renmin Hospital. Nasopharyngeal swabs specimens from the upper respiratory tract that were obtained from all patients at admission were maintained in viral transport medium. SARS-CoV-2 infection was confirmed by real-time RT-PCR using the same protocol as described previously6.All patients were given chest CT examinations.