CXCL8 and infection: The median serum levels of IL-8 for neonates with definite infection (positive culture) versus neonates without definite infection were 440.7 Pg/ml (268.1-636.1 Pg/ml, CI 95%) vs. 21.1 Pg/ml (12-281 Pg/ml, CI 95%), respectively (P<0.001).