title: Accurate diagnosis of acute pyelonephritis: How helpful is procalcitonin?
abstract: OBJECTIVE
  This prospective study aimed to investigate the diagnostic value of serum procalcitonin levels in children with acute pyelonephritis documented by Tc-dimercaptosuccinic acid (DMSA) scintigraphy.
  
  
  METHODS
  We compared the symptoms and laboratory findings of fever, vomiting, abdominal/flank pain, leukocyte count, serum C-reactive protein and procalcitonin levels with the results of the DMSA scan obtained within the first 72 h after referral in children who were diagnosed as having acute pyelonephritis. Thirty-three children (31 female and two male) aged 1-11 years (mean 4.42 years) were enrolled in this prospective study.
  
  
  RESULTS
  Twenty-one of 33 patients (64%) had positive DMSA scans. On the scans obtained after 6 months, five of 21 patients (23.8%) had renal scars. No correlation was found between clinical and laboratory parameters, alone or combined with each other, and positive DMSA scans. Serum procalcitonin levels were 0.767+/-0.64 and 1.23+/-1.17 ng . ml in children with normal and positive DMSA scans, respectively. The cut-off value for procalcitonin using receiver operating characteristic analysis was 0.9605 ng . ml, while sensitivity and specificity were 86.4% and 36.4%, respectively. However, if the cut-off value was chosen as 2 ng . ml, the sensitivity increased to 100% while specificity did not change markedly.
  
  
  CONCLUSIONS
  The serum procalcitonin test, like other commonly used laboratory parameters, e.g. serum C-reactive protein and white blood cell count, was inadequate in distinguishing renal parenchymal involvement in acute febrile urinary tract infections.
authors.affiliation: Department of Paediatrics, Akdeniz University, School of Medicine, Antalya, Turkey.
authors.forename: Ayfer G
authors.initials: AG
authors.lastname: Güven
authors.forename: Halis Z
authors.initials: HZ
authors.lastname: Kazdal
authors.forename: Mustafa
authors.initials: M
authors.lastname: Koyun
authors.forename: Funda
authors.initials: F
authors.lastname: Aydn
authors.forename: Frat
authors.initials: F
authors.lastname: Güngör
authors.forename: Sema
authors.initials: S
authors.lastname: Akman
authors.forename: Yunus Emre
authors.initials: YE
authors.lastname: Baysal
mesh_terms: D000208:Acute Disease; D002097:C-Reactive Protein / Q000378:metabolism; D002116:Calcitonin / Q000097:blood / Q000378:metabolism*; D015740:Calcitonin Gene-Related Peptide; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007668:Kidney / Q000378:metabolism; D007958:Leukocyte Count; D008297:Male; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood / Q000378:metabolism*; D011704:Pyelonephritis / Q000175:diagnosis*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
chemical_list: C000606589:CALCA protein, human; D011498:Protein Precursors; D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide