Role of initial and follow-up IL-6 (interleukin-6) titre in COVID-19 pneumonia: a single center experience

ABSTRACT

Background: Robust data of IL-6 is available in bacterial infection, and now it can be utilized in currently ongoing COVID-19 (corona virus disease-19) pneumonia pandemic to guide treatment strategy as marker of inflammation. Methods: Prospective, observational study included 1,000 COVID-19 cases confirmed with RT PCR (reverse transcription polymerase chain reaction). All cases were undergone categorized after clinical details, HRCT (high resolution computerized tomography) thorax, oxygen saturation, IL-6 (interleukin 6) at entry point and follow up. Age, gender, comorbidity and use BIPAP/NIV (bilevel positive airway pressure/non-invasive ventilation), and outcome as with or without lung fibrosis as per HRCT severity were key observations. Statistical analysis is done by using Chi-square test. Results: In study of 1,000 COVID-19 pneumonia cases, age (<50 and >50 years) and gender has significant association with IL-6. HRCT severity score at entry point has significant correlation with IL-6 level (p < 0.00001). IL-6 level has significant association with duration of illness (p < 0.00001). Comorbidities has significant association with IL-6 level (p < 0.00001). IL-6 level has significant association with oxygen saturation (p < 0.00001). BIPAP/NIV requirement has significant association with IL-6 level (p < 0.00001). Timing of BIPAP/NIV requirement during course of hospitalization has significant association with IL-6 level (p < 0.00001). Follow-up IL-6 titer during hospitalization as compared to entry point normal and abnormal IL-6 has significant association with post-COVID-19 lung fibrosis, respectively (p < 0.00001). Conclusion: IL-6 has very crucialrole in COVID-19 pneumonia in predicting severity of illness, progression of illness including 'cytokine storm' and assessing response to treatment during hospitalization and follow-up titers in analyzing post-COVID-19 lung fibrosis.