title: Do serum C-reactive protein and interleukin-6 predict kidney scarring after urinary tract infection?
abstract: OBJECTIVE
  To investigate if serum C-reactive protein (s-CRP) and interleukin 6 (s-IL6) provide information for predicting renal damage and for DMSA patient selection in children with urinary tract infection (UTI).
  
  
  METHODS
  This observational study was carried out in children with UTI. s-CRP and s-IL6 were measured at UTI diagnosis. Patients forming renal scarring were identified by DMSA scans. The usefulness of s-CRP and s-IL6 measurements for nephropathy scarring diagnosis was evaluated using diagnostic quality and efficiency indexes.
  
  
  RESULTS
  Thirty-two children were included in the study. Eight showed renal scarring after the follow-up. The s-CRP was 110.23 ± 59.69 mg/L and 52.46 ± 63.13 mg/L for patients with and without renal scarring. The s-IL6 concentration was 18.34 ± 11.80 pg/mL and 8.07 ± 9.51 pg/mL respectively. The cut-off points for optimum nephropathy scarring diagnosis were 115 mg/L for s-CRP and 20 pg/mL for s-IL6. The value of highest sensitivity for s-CRP was >5 mg/L (S:100 %) and greatest specificity was >150 mg/L (Sp:95.83). The highest sensitivity for s-IL6 was >4 pg/mL (S:100 %) and the maximum specificity was >40 pg/mL (Sp:100 %).
  
  
  CONCLUSIONS
  Results confirm that children who will develop renal scarring show higher levels of s-IL6 and s-CRP at UTI diagnosis. However, none of the techniques provide sufficient information for predicting renal damage in all patients and for DMSA patient selection.
authors.affiliation: Department of Pediatric Nephrology, Complejo Asistencial Universitario (CAULE), León, Spain, luism@arrakis.es.
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Rodríguez
authors.forename: Belén
authors.initials: B
authors.lastname: Robles
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Marugán
authors.forename: Angeles
authors.initials: A
authors.lastname: Suárez
authors.forename: José María
authors.initials: JM
authors.lastname: García Ruiz de Morales
mesh_terms: D002097:C-Reactive Protein / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D002921:Cicatrix / Q000473:pathology; D005260:Female; D006801:Humans; D007223:Infant; D015850:Interleukin-6 / Q000097:blood*; D007668:Kidney / Q000473:pathology*; D008297:Male; D012680:Sensitivity and Specificity; D014552:Urinary Tract Infections / Q000473:pathology*
chemical_list: D015850:Interleukin-6; D002097:C-Reactive Protein