Role of initial and follow-up IL-6 (Interleukin-6) titre in COVID-19 pneumonia: A single center experience
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MIMSR Medical College, Latur, INDIA
Venkatesh Chest Hospital and Critical Care Center Latur, INDIA
Internal Medicine, MIMSR Medical College, Latur, INDIA
Department of Pathology, MIMSR Medical College, Latur, INDIA
Publication date: 2022-06-29
Electron J Gen Med 2022;19(5):em390
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.

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.

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).

IL-6 has very crucial role 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.

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