IL6 and lymphopenia: In a meta-analysis of 40 studies conducted by Melo et al. (2021), it was concluded that elevated levels of IL-6, CRP, LDH, D-dimer, procalcitonin, aspartate aminotransferase, creatinine, leukocytes, and neutrophils with lymphopenia and thrombocytopenia are important biomarkers of CRS [31].