- SARS-CoV-2 infection confirmed by real time-PCR - Positive imaging: consolidation, ground glass opacities, or bilateral pulmonary infiltration either by CT-scan or chest x-ray, - Need of oxygen therapy to maintain SO2>94% OR FiO2/PaO2 < 22 - and at least two of the following laboratory parameters: * CRP level >70 mg/L or CRP level >= 40 mg/L and doubled within 48 hours (without other confirmed infectious or non-infectious course), * Lactatdehydrogenase > 250 U/L, * thrombocytopenia < 120 x 10E9/L, * lymphocyte count < 0.6 x 10E9/L, * D-dimer > 1 ug/mL, * serum ferritin > 300 ug/mL

- SARS-CoV-2 infection confirmed by real time-PCR - Positive imaging: consolidation, ground glass opacities, or bilateral pulmonary infiltration either by CT-scan or chest x-ray, - Need of oxygen therapy to maintain SO2>94% OR FiO2/PaO2 < 22 - and at least two of the following laboratory parameters: * CRP level >70 mg/L or CRP level >= 40 mg/L and doubled within 48 hours (without other confirmed infectious or non-infectious course), * Lactatdehydrogenase > 250 U/L, * thrombocytopenia < 120 x 10E9/L, * lymphocyte count < 0.6 x 10E9/L, * D-dimer > 1 ug/mL, * serum ferritin > 300 ug/mL