Study design
Ethical approval of this monocentric retrospective study was delivered
by the review board of our hospital (Hospitals of Tours, François
Rabelais University, France). From March 19th to April 28th 2020, we
included 349 patients either suspected of COVID-19 infection or previous
RT-PCR COVID-19 positive patients to whom a chest CT scan was performed
in the radiology department.
Inclusion criteria were: clinical suspicion of COVID-19 infection with
severe symptoms requiring hospitalization or other comorbidities listed
below : patients previously hospitalized for another reason and
suspected of COVID-19 infection, patients with initial negative RT-PCR
presenting a clinical deterioration during their hospitalization.
Comorbidities were : age > 65 years, chronic respiratory
disease, dialysis, cardiac insufficiency NYHA 3 or 4, history of cardiac
diseases (arterial hypertension, coronaropathy, stroke, cardiac
surgery), cirrhosis (≥ Child B), diabetes with complications or
requiring insulin therapy, immunosupression (chemotherapy, biotherapy,
immunosuppressive corticotherapy, uncontrolled HIV or CD4 <
200/mm3, metastatic cancer, all types of graft), BMI
> 40, or pregnancy. Clinical severity scale was assessed
according to the Chinese Center of Disease Control and Prevention :
uncomplicated illness (upper respiratory tract damages, including mild
fever, cough (dry), sore throat, nasal congestion, headache, myalgia, or
malaise. Symptoms of a more serious disease, such as dyspnoea, are not
present), moderate pneumonia with dyspnoea, severe pneumonia (Sp02
< 90 % in ambient air, tachypnoea > 30/min), and
acute respiratory distress syndrome (clinical and ventilation criteria :
mild acute respiratory distress syndrome (ARDS) = 200 mmHg <
PaO2/FiO2 ≤ 300 mmHg (positive PEEP or CPAP ≥ 5 mmHg if not ventilated
or non-invasive ventilation)), moderate ARDS = 100 mmHg <
PaO2/FiO2 ≤ 200 mmHg, and severe ARDS = PaO2/FiO2 ≤ 100
mmHg).16,17