Interleukin-6 as a marker of infection generalization in neonatal sepsis

Objective. To assess the prognostic value of serum cytokine profile (interleukin (IL)-6, IL-8, IL-1, tumor necrosis factor — TNF) for diagnosis of neonatal sepsis. Material and methods. We examined blood in 46 ICU newborns in the following groups: no signs of infectious-septic process (n=34), focus of infection without generalization (n=32) and sepsis (n=7). We took blood samples on the 1st day after admission and on the 8th day in patients with infectious complications. We analyzed serum cytokines using ELISA method (Vector-Best, Russia). Results. Sepsis was accompanied by IL-6 increase within 15.3—89.8%, infectious focus without signs of generalization — (–24.4)— (–72.8)% (p=0.027). A 20% drop in IL-6 levels was chosen as the cut-off point and hospital-stay was compared using Kaplan-Meier analysis. The median of hospital-stay was 16 and 36 days (p=0.007), ICU-stay — was 6 and 27 days (p=0.010) in the groups with favorable and unfavorable prognosis, respectively. Conclusion. IL-6 decrease by less than 20% within a week compared to baseline value is a favorable prognostic factor indicating low probability of progression of infectious and septic complications.