RESUMEN
C-reactive protein [CRP] is the most common marker used for neonatal bacterial sepsis [NBS]. Because of a delay in levels increase, a sequential determination is necessary. Procalcitonin [PCT] and interleukin-6 [IL 6] have been proposed for NBS diagnosis. We measured CRP, PCT, and IL 6 concentrations on admission and after 24 hours in neonates with bacterial sepsis [group A, 20 neonates], probable infection with or without colonization [group B, 20 neonates], and healthy neonates [group C, 20 neonates]. The cutoff values were: CRP >/= 10mg/l; PCT > 3 micro g/ml; and IL 6 > 100 pg/ml. The sensitivity for dosages 1 and 2 were respectively [group A versus group C]: CRP 75% and 80%, PCT 100%, and 95%, IL 6 100%, and 85%. Specificity: CRP 100% and 100%, PCT 90% and 90%, IL 6 95% and 90%. CRP is a useful marker of NBS but PCT and IL 6 have better sensitivities indicating an earlier response. PCT and IL 6 are complementary markers of NBS