title: Procalcitonin and C-reactive protein in urinary tract infection diagnosis.
abstract: BACKGROUND
  Urinary infections are a common type of pediatric disease, and their treatment and prognosis are closely correlated with infection location. Common clinical manifestations and laboratory tests are insufficient to differentiate between acute pyelonephritis and lower urinary tract infection. This study was conducted to explore a diagnostic method for upper and lower urinary tract infection differentiation.
  
  
  METHODS
  The diagnostic values of procalcitonin (PCT) and C-reactive protein (CRP) were analyzed using the receiver operating characteristic curve method for upper and lower urinary tract infection differentiation. PCT was determined using chemiluminescent immunoassay.
  
  
  RESULTS
  The PCT and CRP values in children with acute pyelonephritis were significantly higher than those in children with lower urinary tract infection (3.90 ± 3.51 ng/ml and 68.17 ± 39.42 mg/l vs. 0.48 ± 0.39 ng/ml and 21.39 ± 14.92 mg/l). The PCT values were correlated with the degree of renal involvement, whereas the CRP values failed to show such a significant correlation. PCT had a sensitivity of 90.47% and a specificity of 88% in predicting nephropathia, whereas CRP had sensitivity of 85.71% and a specificity of 48%.
  
  
  CONCLUSIONS
  Both PCT and CRP can be used for upper and lower urinary tract infection differentiation, but PCT has higher sensitivity and specificity in predicting pyelonephritis than CRP. PCT showed better results than CRP. PCT values were also correlated with the degree of renal involvement.
authors.affiliation: Department of Pediatrics, Qilu Hospital of Shan Dong University, Jinan 250012, China. zjqqcn@126.com.
authors.forename: Rui-Ying
authors.initials: RY
authors.lastname: Xu
authors.forename: Hua-Wei
authors.initials: HW
authors.lastname: Liu
authors.forename: Ji-Ling
authors.initials: JL
authors.lastname: Liu
authors.forename: Jun-Hua
authors.initials: JH
authors.lastname: Dong
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011498:Protein Precursors / Q000097:blood*; D011704:Pyelonephritis / Q000097:blood* / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014552:Urinary Tract Infections / Q000097:blood* / Q000175:diagnosis*
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide