title: Usefulness of neutrophil-lymphocyte ratio in young children with febrile urinary tract infection.
abstract: OBJECTIVE
  Acute pyelonephritis (APN) is a serious bacterial infection that can cause renal scarring in children. Early identification of APN is critical to improve treatment outcomes. The neutrophil-lymphocyte ratio (NLR) is a prognostic marker of many diseases, but it has not yet been established in urinary tract infection (UTI). The aim of this study was to determine whether NLR is a useful marker to predict APN or vesicoureteral reflux (VUR).
  
  
  METHODS
  We retrospectively evaluated 298 pediatric patients (age≤36 months) with febrile UTI from January 2010 to December 2014. Conventional infection markers (white blood cell [WBC] count, erythrocyte sedimentation rate [ESR], C-reactive protein [CRP]), and NLR were measured.
  
  
  RESULTS
  WBC, CRP, ESR, and NLR were higher in APN than in lower UTI (P<0.001). Multiple logistic regression analyses showed that NLR was a predictive factor for positive dimercaptosuccinic acid (DMSA) defects (P<0.001). The area under the receiver operating characteristic (ROC) curve was high for NLR (P<0.001) as well as CRP (P<0.001) for prediction of DMSA defects. NLR showed the highest area under the ROC curve for diagnosis of VUR (P<0.001).
  
  
  CONCLUSIONS
  NLR can be used as a diagnostic marker of APN with DMSA defect, showing better results than those of conventional markers for VUR prediction.
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.; Department of Pediatric Nephrology, Severance Children's Hospital, Seoul, Korea.
authors.forename: Song Yi
authors.initials: SY
authors.lastname: Han
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.; Department of Pediatric Nephrology, Severance Children's Hospital, Seoul, Korea.
authors.forename: I Re
authors.initials: IR
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Daewoo General Hospital, Ajou University School of Medicine, Geoje, Korea.
authors.forename: Se Jin
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ji Hong
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.; Department of Pediatric Nephrology, Severance Children's Hospital, Seoul, Korea.
authors.forename: Jae Il
authors.initials: JI
authors.lastname: Shin
keywords: Child; Neutrophil-lymphocyte ratio; Pyelonephritis; Urinary tract infections; Vesico-ureteral reflux