Prediction of nosocomial sepsis in neonates by means of a computer-weighted bedside scoring system (NOSEP score)

Abstract

To develop an easy-to-use bedside scoring system, composed of clinical variables, hematologic variables, and risk factors of infection, to predict nosocomial sepsis in neonatal intensive care unit patients. A neonatal intensive care unit in a university hospital, Antwerp, Belgium. Over 2 yrs, we analyzed two groups of patients. First, we prospectively studied 104 episodes of presumed nosocomial sepsis in 80 neonates (derivation cohort), and then we retrospectively studied 50 episodes in 39 neonates (validation cohort). None. We developed two versions of a scoring system to predict nosocomial sepsis in sick neonates. The first scoring system (NOSEP-1 score) was based on 15 clinical, 12 laboratory, and 17 historical variables potentially connected with infection; the second one (NOSEP-2 score) also included the culture results of central vascular catheters. Based on the odds ratios of all independent variables, an additive and weighted score was developed and validated in a cohort of 39 patients screened for nosocomial sepsis in the same center. The NOSEP-1 score consisted of three laboratory variables (C-reactive protein ≥14 mg/L, thrombocytopenia 50%), one clinical factor (fever >38.2°C [100.8°F]), and one risk factor (parenteral nutrition for ≥14 days). The NOSEP-2 score consisted of the same variables plus catheter-hub and catheter insertion site colonization data. Receiver operating characteristic curve analysis demonstrated good predictor performance of the NOSEP-1 score (area under the curve [Az] = 0.82 ± 0.04 [sem]) and NOSEP-2 score (Az = 0.84 ± 0.04, p .75). The simple bedside scoring system NOSEP-1 composed of C-reactive protein, neutrophil fraction, thrombocytopenia, fever, and prolonged parenteral nutrition exposure provides a valuable tool for early identification of nosocomial sepsis. Its predictive power can be improved by adding central vascular catheter insertion site and hub colonization to the score.