Flow chart diagram.

ICU: intensive care unit, COVID-19: coronavirus disease 2019. * admission causes other than severe or critical COVID-19 pneumonia: acute kidney injury (n = 3) [hypovolemic Shock, acute pancreatitis, acute limb ischemia], non-traumatic coma (n = 2) [acute ischemic stroke, status epilepticus], cardiogenic choc (n = 2) [acute myocarditis, acute coronary syndrome], postoperative management of cardiac surgery (n = 1), severe metabolic disturbance (n = 2) [diabetic ketoacidosis]. † Viral co-infections were due to the influenza A virus in one patient and the human rhinovirus in another. Fungal superinfections were ventilator-associated pneumonia due to Aspergillus fumigatus in two patients and Cryptococcus neoformans in one patient.