Van den Brand, MarreVan den Dungen, Frank A.M.Bos, Martine P.Van Weissenbruch, Mirjam M.Van Furth, A. MarcelineDe Lange, AnnemiekeRubenjan, AnnaPeters, Remco P.H.Savelkoul, Paul H.M.2018-06-122018-06-122018-04-22Van den Brand, M., Van den Dungen, F.A.M., Bos, M.P. et al. 2018, 'Evaluation of a real-time PCR assay for detection and quantification of bacterial DNA directly in blood of preterm neonates with suspected late-onset sepsis', Critical Care, vol. 22, art. no. 105, pp. 1-10.1364-8535 (print)1466-609X (online)10.1186/s13054-018-2010-4http://hdl.handle.net/2263/65132Additional file 1: Detection of pathogens in blood by blood culture and PCR for polymicrobial infection episodes.BACKGROUND : Rapid and accurate diagnosis of neonatal sepsis is highly warranted because of high associated morbidity and mortality. The aim of this study was to evaluate the performance of a novel multiplex PCR assay for diagnosis of late-onset sepsis and to investigate the value of bacterial DNA load (BDL) determination as a measure of infection severity. METHODS : This cross-sectional study was conducted in a neonatal intensive care unit. Preterm and/or very low birth weight infants suspected for late-onset sepsis were included. Upon suspicion of sepsis, a whole blood sample was drawn for multiplex PCR to detect the eight most common bacteria causing neonatal sepsis, as well as for blood culture. BDL was determined in episodes with a positive multiplex PCR. RESULTS : In total, 91 episodes of suspected sepsis were investigated, and PCR was positive in 53 (58%) and blood culture in 60 (66%) episodes, yielding no significant difference in detection rate (p = 0.17). Multiplex PCR showed a sensitivity of 77%, specificity of 81%, positive predictive value of 87%, and negative predictive value of 68% compared with blood culture. Episodes with discordant results of PCR and blood culture included mainly detection of coagulase-negative staphylococci (CoNS). C-reactive protein (CRP) level and immature to total neutrophil (I/T) ratio were lower in these episodes, indicating less severe disease or even contamination. Median BDL was high (4.1 log10 cfu Eq/ml) with a wide range, and was it higher in episodes with a positive blood culture than in those with a negative blood culture (4.5 versus 2.5 log10 cfu Eq/ml; p < 0.0001). For CoNS infection episodes BDL and CRP were positively associated (p = 0.004), and for Staphylococcus aureus infection episodes there was a positive association between BDL and I/T ratio (p = 0.049). CONCLUSIONS : Multiplex PCR provides a powerful assay to enhance rapid identification of the causative pathogen in late-onset sepsis. BDL measurement may be a useful indicator of severity of infection.en© The Author(s). 2018 Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License.Molecular diagnosisLate-onset sepsisNeonatologyReal-time PCRBacteremiaMeta-analysis (MA)Molecular detectionNecrotizing EnterocolitisRapid diagnosisPolymerase chain reaction (PCR)Stream infectionsBirth weightBacterial DNA load (BDL)Article