Berka I, et al. - This study suggests a great potential of the combination of interleukin-6 (IL-6) and C-reactive protein (CRP) in routine rapid diagnosis of late-onset bloodstream infection (LOBSI) development. Antibiotic treatment could be discontinued early due to high negative predictive value of all tested markers.

• Positive blood culture, clinical signs of infection, and onset more than 72 hours after birth defined LOBSI.

• Relative to other markers (procalcitonin and CRP), IL-6 level was superior.

• For the presence of LOBSI, IL-6 levels greater than 100 ng/L had a sensitivity of 94% and a specificity of 99%.

• The optimal cutoff values of IL-6, CRP, and PCT showed negative predictive values of 99%, 95%, and 93%, respectively.

• In 97.9% of cases, successful prediction of LOBSI was achieved with the logistic regression model of IL-6 > 100 ng/L or CRP > 10 mg/L.