The role of serum interleukin-6 and C-reactive protein levels for differentiating aetiology of neonatal sepsis

Introduction: In our clinical practice, we observed high interleukin-6 (IL-6) levels in gram-negative sepsis. Objective: To investigate the relationship between IL-6 and C-reactive protein (CRP) levels and early determination of neonatal sepsis of gram-negative or gram-positive aetiology. Population and Methods: White blood cell count, IL-6 and CRP levels were compared among different groups. Results: Gram-negative, gram-positive and fungal infection groups consisted of 73, 82 and 15 patients, respectively. The optimal cut-off levels of IL-6 between gram-negative and gram-positive fungal infection groups were 202 and 57 pg/ ml. The fungal infection group had higher CRP levels than gram-negative and positive infection groups. Conclusions: To our knowledge, this is the largest reported study aiming at determining of IL-6 cut-off levels to differentiate neonatal sepsis aetiology. Gram-negative microorganisms led to 10 fold higher IL-6 production. The evaluation of IL-6 and CRP is useful to diagnose and also differentiate neonatal sepsis aetiology.