TNF-Α, IL-1Β and IL-6 Levels in Pandemic Influenza A (H1N1) 2009 Patients and Effect on Mortality

Abstract

Introduction: Throughout history, influenza virus pandemics have led to the death of millions of people. The virus sometimes causes pathological changes that can lead to severe illness and death. Inflammatory cytokines and chemokines have been shown to be involved in the pathogenesis of tissue damage in the lungs of animals and humans infected with influenza viruses. Materials and Methods: The serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin- 6 (IL-6) were determined with enzyme immunoassay (EIA) in 57 patients who were hospitalized with confirmed influenza and a control group. Results: Fifty-seven patients with confirmed influenza A (H1N1) 2009 and 62 healthy subjects as the control group were included in this study. Of these patients with influenza, 51 (89.4%) were discharged, and 6 (10.5%) died of influenza-related illness. TNF-α levels were found to be 43.0 pg/mL in fatal patients, 20.9 pg/mL in non-fatal patients, and 4.1 pg/mL in the control group. IL-6 levels were found to be 1074.12 pg/mL in fatal patients, 191.0 pg/mL in non-fatal patients, and 36.1 pg/mL in the control group. The differences between groups were statistically significant (p= 0.003 and p< 0.001, respectively). IL-1β levels were found to be 2.1 pg/mL in fatal patients, 7.1 pg/mL in non-fatal patients, and 7.5 pg/mL in the control group, and the difference was not statistically significant (p= 0.657). Conclusion: We found that TNF-α and IL-6 levels were significantly higher in patients who died. We suggest that higher levels of pro-inflammatory cytokines may be used as an important marker of mortality.

Keywords

• Influenza A virus H1N1 subtype
• tumor necrosis factor-alpha
• interleukin-1beta
• interleukin-6