From the Guidelines
Extremely high levels of interleukin-6 (IL-6) are most notably associated with severe COVID-19 infection, as evidenced by elevated IL-6 levels in patients with severe COVID-19, which were associated with increased mortality 1.
Conditions with High IL-6 Levels
The following conditions are associated with extremely high IL-6 levels:
- Severe COVID-19 infection
- Cytokine release syndrome (CRS) following CAR-T cell therapy
- Systemic inflammatory response syndrome (SIRS)
- Sepsis
- Certain autoimmune disorders like rheumatoid arthritis and systemic lupus erythematosus
- Castleman disease
- Certain lymphomas
- Severe tissue injury such as major trauma or burns
Treatment Options
Treatment for conditions with extremely high IL-6 often includes IL-6 inhibitors like tocilizumab or sarilumab, which block the IL-6 receptor and help reduce the inflammatory response 1.
Key Considerations
- IL-6 inhibitors have been shown to be effective in reducing mortality and mechanical ventilation in patients with severe COVID-19 1
- The use of IL-1 and IL-6 inhibitors should be prioritized to avoid prolonged systemic glucocorticoid (GC) use 1
- Early initiation of IL-1 or IL-6 inhibitors is associated with favorable short-term outcomes in patients with Still's disease 1
From the Research
Diseases Causing High IL-6 Levels
- COVID-19 is associated with extremely high Interleukin-6 (IL-6) levels, particularly in severe cases 2, 3, 4, 5, 6
- IL-6 levels are significantly elevated in COVID-19 patients, suggesting a cytokine storm 2, 5, 6
- High IL-6 levels are predictive of disease severity and poor prognosis in COVID-19 patients 5, 6
Characteristics of High IL-6 Levels in COVID-19
- IL-6 levels are higher in non-survivors than in survivors 5
- Maximal IL-6 values are significantly higher in non-survivors than in survivors 5
- Repeated measurements of IL-6 can help identify critically ill COVID-19 patients with a high risk of poor prognosis 5
- IL-6 and IL-10 levels are significantly higher in critical COVID-19 patients than in moderate and severe patients 6