Investigation of the correlation between serum levels of interleukin-6 and clinical and paraclinical findings in COVID-19 patients

Background COVID-19 frequently presents with pneumonia. Impaired immune function, particularly in older adults and immunocompromised individuals, increases susceptibility to infection and contributes to higher morbidity and mortality. Among inflammatory cytokines, Interleukin-6 (IL-6) plays a pivotal role in immune dysregulation and cytokine storm. Therefore, this study aimed to investigate the association between serum IL-6 levels and clinical, laboratory, radiological, and outcome-related findings among hospitalized patients with COVID-19. Methods This descriptive-analytical cross-sectional study included 210 hospitalized COVID-19 patients at Shahid Beheshti Hospital, Kashan. Serum IL-6 was measured as part of their diagnostic and therapeutic workup. Demographic characteristics, clinical manifestations, laboratory markers, imaging findings, and outcomes were recorded. Patients with incomplete data were excluded. Data were analyzed using SPSS software version 26. Results The mean age of patients was 50.37±17.48 years, with a slight male predominance (51%). Hypertension was the most common comorbidity (31.9%). Abnormal laboratory markers included elevated LDH (64.3%), ESR (61.0%), lymphopenia (59.5%), and CRP (58.6%). Pulmonary involvement on CT was noted in 91.5% of patients, with moderate involvement most frequent (41.4%). ICU admission occurred in 17.1% and mechanical ventilation was required in 10.5%. The mean CALL score was 8.63±2.33, and average hospital stay was 6.70±5.27 days. Serum IL-6 levels were significantly associated (p<0.05) with age, oxygen saturation, lymphopenia, LDH, CRP, CT involvement, disease severity, ICU admission, mortality, and length of hospitalization. Conclusion Elevated serum IL-6 strongly reflects disease severity and adverse outcomes in COVID-19, highlighting its potential as a prognostic biomarker to guide clinical assessment and management.