Paradoxically Increased Inflammation in Immunosuppressed Individuals with COVID-19

Abstract

Dysregulated inflammation is central to the morbidity and mortality associated with COVID-19. Treatment with dexamethasone and IL-6 blockade can be life-saving in patients stratified for moderate - severe disease. Patients with suppressed immunity are often excluded from immune blockade therapy due to the assumption that additional suppression of an impaired immune system will be detrimental to viral clearance. We hypothesised that patients with suppressed immune systems would be slower to clear viral infection, leading to increased damage and therefore, paradoxically, a more intense acute phase response to SARS-CoV-2 infection. This was tested by a sub-group analysis of the Coronavirus Immune Response and Clinical Outcomes (CIRCO) cohort, an observational study of acute COVID-19 in Greater Manchester, UK. Patients were included if they were treated with dexamethasone and had a research blood sample retrieved within 48 hours of admission, and excluded if they were treated with IL-6 blockade or antiviral therapy prior to research sampling. Acute phase serum cytokine levels were compared between eight immunosuppressed and 12 immunocompetent patients positive for SARS-CoV-2. In support of our hypothesis, we found that immunosuppressed individuals had higher levels of the inflammatory cytokines IP-10 (p=0.03) and MCP-1 (p=0.01) compared to immunocompetent patients matched for COVID-19 severity. This suggests that immunosuppressed patients may benefit as much as immunocompetent individuals from systemic treatments to dampen inflammation in COVID-19, and current recommendations of excluding these patients from treatment solely on the basis of immune competence may need to be re-evaluated.