title: Identification of children and adolescents at risk for renal scarring after a first urinary tract infection: a meta-analysis with individual patient data.
abstract: OBJECTIVE
  No studies have systematically examined the accuracy of clinical, laboratory, and imaging variables in detecting renal scarring in children and adolescents with a first urinary tract infection.
  
  
  OBJECTIVE
  To identify independent prognostic factors for the development of renal scarring and to combine these factors in prediction models that could be useful in clinical practice.
  
  
  METHODS
  MEDLINE and EMBASE.
  
  
  METHODS
  We included patients aged 0 to 18 years with a first urinary tract infection who underwent follow-up renal scanning with technetium Tc 99m succimer at least 5 months later.
  
  
  METHODS
  We pooled individual patient data from 9 cohort studies.
  
  
  METHODS
  We examined the association between predictor variables assessed at the time of the first urinary tract infection and the development of renal scarring. Renal scarring was defined by the presence of photopenia on the renal scan. We assessed the following 3 models: clinical (demographic information, fever, and etiologic organism) and ultrasonographic findings (model 1); model 1 plus serum levels of inflammatory markers (model 2); and model 2 plus voiding cystourethrogram findings (model 3).
  
  
  RESULTS
  Of the 1280 included participants, 199 (15.5%) had renal scarring. A temperature of at least 39°C, an etiologic organism other than Escherichia coli, an abnormal ultrasonographic finding, polymorphonuclear cell count of greater than 60%, C-reactive protein level of greater than 40 mg/L, and presence of vesicoureteral reflux were all associated with the development of renal scars (P ≤ .01 for all). Although the presence of grade IV or V vesicoureteral reflux was the strongest predictor of renal scarring, this degree of reflux was present in only 4.1% of patients. The overall predictive ability of model 1 with 3 variables (temperature, ultrasonographic findings, and etiologic organism) was only 3% to 5% less than the predictive ability of models requiring a blood draw and/or a voiding cystourethrogram. Patients with a model 1 score of 2 or more (21.7% of the sample) represent a particularly high-risk group in whom the risk for renal scarring was 30.7%. At this cutoff, model 1 identified 44.9% of patients with eventual renal scarring.
  
  
  CONCLUSIONS
  Children and adolescents with an abnormal renal ultrasonographic finding or with a combination of high fever (≥39°C) and an etiologic organism other than E coli are at high risk for the development of renal scarring.
authors.affiliation: Division of General Academic Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania2Division of General Academic Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Nader
authors.initials: N
authors.lastname: Shaikh
authors.affiliation: Department of Paediatric Nephrology, Children's Hospital at Westmead and Sydney School of Public Health, University of Sydney, Sydney, Australia.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Craig
authors.affiliation: Departments of Operating Rooms and Health Evidence, Radboud University Medical Center Nijmegen, Nijmegen, the Netherlands.
authors.forename: Maroeska M
authors.initials: MM
authors.lastname: Rovers
authors.affiliation: Department of Woman's and Child's Health, University of Padova, Padova, Italy.
authors.forename: Liviana
authors.initials: L
authors.lastname: Da Dalt
authors.affiliation: Department of Pediatric Surgery, Alexandroupolis University Hospital, Democritus University of Thrace School of Medicine, Alexandroupolis, Greece.
authors.forename: Stefanos
authors.initials: S
authors.lastname: Gardikis
authors.affiliation: Division of General Academic Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Hoberman
authors.affiliation: Dialysis Unit, Department of Pediatrics and Nephrology, Azienda Ospedaliero Universitaria Sant'Orsola-Malpighi Bologna, Bologna, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Montini
authors.affiliation: Department of Pediatrics, Germans Trias i Pujol University Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Rodrigo
authors.affiliation: Department of Pediatric Surgery, Children's Hospital, University of Helsinki, Helsinki, Finland.
authors.forename: Seppo
authors.initials: S
authors.lastname: Taskinen
authors.affiliation: Service de Pédiatrie, Université Catholique de Louvain, University Medical Centre Mont-Godinne, Yvoir, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Tuerlinckx
authors.affiliation: Division of General Academic Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Timothy
authors.initials: T
authors.lastname: Shope
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002921:Cicatrix / Q000382:microbiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007674:Kidney Diseases / Q000382:microbiology*; D008297:Male; D012307:Risk Factors; D014552:Urinary Tract Infections / Q000150:complications*