Immune-inflammatory biomarkers' panel for severe COVID-19 patients

ABSTRACT

Background: Severe acute respiratory syndrome caused by novel coronavirus 2 (SARS-CoV-2) emerged in Wuhan (China) in December 2019. This study aimed to evaluate a panel of biomarkers in order to better phenotype population and to define the role of mediators as biomarkers of severity.Materials and methods: Serum samples were obtained from 24 COVID-19 patients at the hospital admission before any treatments and infusion of intravenous steroids or invasive ventilation. KL-6 IL-6 and C peptide were measured with CLEIA methods. IL-6 assays were validated for accuracy and precision. The validity of variables used to distinguish severe from mild-to-moderate group was assessed by areas under curves (AUC) in the receiver operating characteristic (ROC) and a logistic regression was performed to combine parameters between the two groups.Results: In severe group, IL-6 CRP and KL-6 concentrations were significantly increased than mild-to-moderate patients. Moreover KL-6, IL-6 and CRP biomarkers resulted directly correlated. In the logistic regression, ROC curve analysis of the model comprise IL-6, KL-6 and CRP reported the best performance with an AUC 0,95. Conclusions: On corroborating previous reports on IL-6 over-expression in severe COVID 19 patients requiring mechanical ventilation, the analytical determination of other mediators showed that IL-6 concentrations are correlated with those of KL-6 and CRP. The combination of three prognostic bioindicators allowed to discriminate between severe COVID-19 patients with poor prognosis from mild-tomoderate patients.