title: Association of procalcitonin with acute pyelonephritis and renal scars in pediatric UTI.
abstract: OBJECTIVE
  Urinary tract infections (UTIs) are common childhood bacterial infections that may involve renal parenchymal infection (acute pyelonephritis [APN]) followed by late scarring. Prompt, high-quality diagnosis of APN and later identification of children with scarring are important for preventing future complications. Examination via dimercaptosuccinic acid scanning is the current clinical gold standard but is not routinely performed. A more accessible assay could therefore prove useful. Our goal was to study procalcitonin as a predictor for both APN and scarring in children with UTI.
  
  
  METHODS
  A systematic review and meta-analysis of individual patient data were performed; all data were gathered from children with UTIs who had undergone both procalcitonin measurement and dimercaptosuccinic acid scanning.
  
  
  RESULTS
  A total of 1011 patients (APN in 60.6%, late scarring in 25.7%) were included from 18 studies. Procalcitonin as a continuous, class, and binary variable was associated with APN and scarring (P < .001) and demonstrated a significantly higher (P < .05) area under the receiver operating characteristic curve than either C-reactive protein or white blood cell count for both pathologies. Procalcitonin ≥0.5 ng/mL yielded an adjusted odds ratio of 7.9 (95% confidence interval [CI]: 5.8-10.9) with 71% sensitivity (95% CI: 67-74) and 72% specificity (95% CI: 67-76) for APN. Procalcitonin ≥0.5 ng/mL was significantly associated with late scarring (adjusted odds ratio: 3.4 [95% CI: 2.1-5.7]) with 79% sensitivity (95% CI: 71-85) and 50% specificity (95% CI: 45-54).
  
  
  CONCLUSIONS
  Procalcitonin was a more robust predictor compared with C-reactive protein or white blood cell count for selectively identifying children who had APN during the early stages of UTI, as well as those with late scarring.
authors: Centre for Statistics in Medicine, University of Oxford, Oxford, UK. sandrin.leroy@gmail.com
authors: Sandrine
authors: S
authors: Leroy
authors: Anna
authors: A
authors: Fernandez-Lopez
authors: Roya
authors: R
authors: Nikfar
authors: Carla
authors: C
authors: Romanello
authors: François
authors: F
authors: Bouissou
authors: Alain
authors: A
authors: Gervaix
authors: Metin K
authors: MK
authors: Gurgoze
authors: Silvia
authors: S
authors: Bressan
authors: Vladislav
authors: V
authors: Smolkin
authors: David
authors: D
authors: Tuerlinckx
authors: Constantinos J
authors: CJ
authors: Stefanidis
authors: Georgos
authors: G
authors: Vaos
authors: Pierre
authors: P
authors: Leblond
authors: Firat
authors: F
authors: Gungor
authors: Dominique
authors: D
authors: Gendrel
authors: Martin
authors: M
authors: Chalumeau
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D002116:Calcitonin / Q000097:blood* / Q000378:metabolism; D015740:Calcitonin Gene-Related Peptide; D002648:Child; D002675:Child, Preschool; D002921:Cicatrix / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D016001:Confidence Intervals; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D016013:Likelihood Functions; D008297:Male; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011498:Protein Precursors / Q000097:blood* / Q000378:metabolism; D011704:Pyelonephritis / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D018570:Risk Assessment; D012720:Severity of Illness Index; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide
keywords: acute pyelonephritis; children; procalcitonin; renal scarring; urinary tract infection