2.6 Severe disease criteria
Patients from any group presented with any one of the following were categorized to have a severe disease:
  1. Oxygen requirement of more than 10 liters for 90% saturation.
  2. 50% of lung involvement on either chest X-ray or HRCT.
  3. Multi-organ dysfunction
  4. CRP > 10 mg/L, D-dimer > 1000 mg/mL, serum ferritin > 1000 ng/mL.
  5. Secondary infection (diagnosed by blood culture and sensitivity test or raised procalcitonin).
  6. Shock or use of inotropes.
  7. [PaO2/FiO2] (PF ratio) < 118 mmHg.