2.9 Data collection and procedure
After taking informed consent from the enrolled patients, their blood sample was drawn according to standard operating procedures within 24 hours of admission and sent to the laboratory for routine laboratory tests that included complete blood count (CBC), liver function tests (LFTs), renal functional tests (RFTs) and serum electrolytes. CBC was analyzed using the hospital laboratory system, ’Sysmex analyzer’. The inflammatory markers such as neutrophil/lymphocyte ratio (NLR), C-reactive protein (CRP), serum albumin (ALB), and serum fibrinogen (FIB) were also ordered. The patients were then sent for a chest X-ray. HRCT chest scan was conducted on the advice of the respiratory physicians.
NLR ratio was calculated using the simple formula:
If a patient belonged to the heavy group, additional investigations (D-dimer level and serum ferritin) were also ordered. Where indicated, their sputum or blood culture, or serum procalcitonin was also ordered.
Simultaneously, patient demographic characteristics (gender and age), comorbidities (hypertension (HTN), diabetes mellitus (DM), coronary heart disease (CHD), lung diseases such as asthma or chronic obstructive pulmonary disease (COPD)), clinical manifestations of COVID-19 (fever, chest pain, cough and shortness of breath), medication history (including the use of long-term steroid), and history of lung malignancy were recorded on a data collection form.