Association of SARS-CoV-2 infection with long-lasting increase in circulating IL-32 levels

Background & aims Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection has a wide spectrum of clinical presentations ranging from asymptomatic viral replication to hyper-inflammatory syndrome and respiratory failure and can trigger immune disorders and long-COVID. Interleukin-32 (IL-32) is a pro-inflammatory cytokine induced during viral infections and chronic pulmonary disease. Aim Aim of this study was to investigate the impact of the SARS-CoV-2 pandemic and severe COVID-19 on circulating IL-32 levels. Study design Observational retrospective biomarker study. Patients & methods We analyzed 949 healthy blood donors (pre-pandemic and pandemic-era) and 212 patients hospitalized due to severe COVID-19 during the first five infection waves. IL-32 levels were measured by ELISA. Results Pandemic-era blood plasma donors showed a +0.78 ± 0.09 log 10 pg/ml mean increase in IL-32 (pandemic-era 2.91 ± 0.05 vs. pre-pandemic 2.14 ± 0.07 log 10 pg/ml, p