Biochemical analysis
Serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) were measured on Siemens Advia 1800 Chemisty System (Siemens Healthcare Diagnostics, Newark, Germany) while ferritin levels were performed via Siemens Advia Centaur XP Immunassay System (Siemens Healthcare Diagnostics, Newark, Germany). CRP was determined by Siemens Dade Behring BN II System (Siemens Healthcare Diagnostics, Marburg, Germany) via nepholometric method. Leukocyte, neutrophils, lymphocytes, eosinophils, and platelet counts in participating subjects were determined by Mindray BC 6000 Hematology System (MINDRAY Medical International Co., Shenzhen, China). D-dimer levels were studied on VIDAS D-Dimer Exclusion™ II (BioMérieux, France) while fibrinogen was measured on STA Compact Max (Stago, USA). Procalcitonin was measured by Architecht i2000 SR Immunassay Analyzer (Abbott, USA).