Cytokine-Release Patterns in Elderly Patients with Systemic Inflammatory Response Syndrome

BACKGROUND: Information is scarce about the inflammatory responses to infection in elderly patients. OBJECTIVE: To investigate the inflammatory pattern in elderly patients with systemic inflammatory response syndrome (SIRS). METHODS: We assessed the value of pro-inflammatory cytokines (TNF-alpha, IL-6, IL-1beta) and C-reactive protein (CRP) in elderly patients with SIRS at the time of consultation in the emergency room and on the fourth day of hospitalization. RESULTS: Of 100 patients with SIRS, 92 had a clinical suspicion of infection and 46 were microbiologically confirmed. Basal TNF-alpha and IL-6 levels were higher in patients with bacteremia (p < 0.001 and p = 0.017, respectively). Basal levels of TNF-alpha (p < 0.001) and fourth-day levels of CRP (p = 0.004), TNF-alpha (p < 0.001) and IL-6 (p = 0.002) had a positive correlation with the length of hospitalization. Higher IL-6 levels on the fourth day showed a correlation with mortality (p = 0.016), while the other cytokines and CRP did not show this association. CONCLUSION: Febrile elderly patients showed an inflammatory response pattern to infection equivalent to that reported in younger patients. Despite some limitations of our study, among febrile elderly patients, pro-inflammatory cytokine levels can be good markers for evaluating the prognosis of infections.