Aims: The aim of this study was to examine the applicability of the definitions of the systemic inflammatory response syndrome (SIRS) and sepsis to neonates during the first 3 days of life.
Methods: This is a retrospective study of all term neonates hospitalized within the first 24 h of life from 2004 to 2010 at our neonatal intensive care unit.
Results: Of 476 neonates, 30 (6 %) had a diagnosis of culture-proven early-onset sepsis (EOS) and 81 (17 %) had culture-negative clinical EOS or suspected EOS. SIRS and sepsis criteria were applied to 116 (24 %) and 61 (13 %) neonates, respectively. Of 30 neonates with culture proven, EOS 14 (53 %) fulfilled SIRS and sepsis criteria. The single diagnostic criterion of SIRS applied to 20 % (hypothermia or fever), 43 % (white blood cell count/immature-to-total neutrophil ratio), 87 % (respiratory symptoms), and 33 % (cardiocirculatory symptoms) of all neonates with culture-proven EOS.
Conclusions: The definitions of SIRS and sepsis did not apply to about half of all cases of culture-proven EOS. An evidence-based approach to find the appropriate criteria for defining EOS in the neonate is needed.