Relationship Among Disease Severity,Radiological Extention and Serum IL-6 in Patients with COVID19

Background:IL-6 is an important pro-inflammatory cytokine and has been associated with more rapid disease progression and a higher complication rate in COVID-19 cases.Accumlated evidence so far has demonstrated cytokine storm syndrome is associated more severe disease and complications such as respiratory failure, ARDS, septic shock and muliorgan dysfunction. Objective:We aimed to investigate the relationship among IL-6 levels, severity of the disease ,and extention of radiological appearance in patients with COVID19.Methods and measurements:We have assessed 256 moderate-to-severe patients with COVID-19 who have been admitted to the pulmonary medicine and intensive care unit(ICU) departments of hospital clinic of Medical University, Baku city from 10-th April 2020 to 15 -th June 2020.All patients have examined on CT of lung, serum IL-6 levels and all others clinical and laboratory investigations which are included for the examination of the COVID19 patients.Results :Depends on the level of the IL-6 all hospitalized patients with COVID19 have divided in two groups:1)142 patients were with serum IL-6 level >-100 pg/ml;2)114 patients were with serum IL-6 <99 pg/ml.The high levels of serum IL-6( >-100 pg/ml) in patients was associated with more severe disease severity and respiratory failure was positive corellated with high IL-6 levels(OR,4.25[0.85-10.36],95%CI;p<0.001).Kidney failure was common in patients with high level of serum IL-6 compared to low serum IL-6 level(OR,3.71[092- 8.64] 95% CI;p=0.002).In the chest CT findings reviewed for extent of parenchymal involvement more extented involvement were found in patients with high levels of serum IL-6.In all patients with serum low IL-6 levels the domonant infiltration pattern was ground -glass compared(less than <50% involvement) to patients with high serum IL-6 level(OR,4.69[1.12-12.62] 95% CI;p=0.0004).In patients with high serum IL-6 levels the dominant and extented infiltration pattern(more than >50% involvement) were crazy-paving and consolidation( OR,3.58[079-11.34] 95%CI;p=0.002).Low serum IL-6 level in patients had significantly lower rate of pleural effusion compared to the patients with higher serum level of IL-6(p=0.015).On control chest CT, patients with high levels of IL-6 had significantly higher rate of progression and the development of ARDS(OR,6.87[1.75- 14.58] 95% CI;p=0.0001).ICU department admission rate was significantly higher in patients with high serum levels of IL-6(OR,3.65[098-8.43]95% CI;p<0.002) .Conclusions:In hospitalized patients with COVID-19 the high serum IL-6 levels are associated with more severe disease course .In patients the high serum level of IL-6 is associated with more extensive parenchymal involvement with dominant type of infiltration as consolidation and crazy-paving .The increased serum level of IL-6 in patients most commonly were associated with progression of the disease and develpment complication as ARDS.