title: Evaluation of the optimal neutrophil gelatinase-associated lipocalin value as a screening biomarker for urinary tract infections in children.
abstract: BACKGROUND
  Neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker in the detection of kidney injury. Early diagnosis of urinary tract infection (UTI), one of the most common infections in children, is important in order to avert long-term consequences. We assessed whether serum NGAL (sNGAL) or urine NGAL (uNGAL) would be reliable markers of UTI and evaluated the appropriate diagnostic cutoff value for the screening of UTI in children.
  
  
  METHODS
  A total of 812 urine specimens and 323 serum samples, collected from pediatric patients, were analyzed. UTI was diagnosed on the basis of culture results and symptoms reported by the patients. NGAL values were measured by using ELISA.
  
  
  RESULTS
  NGAL values were more elevated in the UTI cases than in the non-UTI cases, but the difference between the values were not statistically significant (P=0.190 for sNGAL and P=0.064 for uNGAL). The optimal diagnostic cutoff values of sNGAL and uNGAL for UTI screening were 65.25 ng/mL and 5.75 ng/mL, respectively.
  
  
  CONCLUSIONS
  We suggest that it is not appropriate to use NGAL as a marker for early diagnosis of UTI in children.
authors.affiliation: Department of Laboratory Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Nae
authors.initials: N
authors.lastname: Yu
authors.affiliation: Department of Laboratory Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Hye Ryoun
authors.initials: HR
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Ki Wook
authors.initials: KW
authors.lastname: Yun
authors.affiliation: Department of Pediatrics, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: In Seok
authors.initials: IS
authors.lastname: Lim
authors.affiliation: Department of Urology, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Tae Hyoung
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Mi-Kyung
authors.initials: MK
authors.lastname: Lee
mesh_terms: D000209:Acute-Phase Proteins / Q000652:urine*; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002648:Child; D002675:Child, Preschool; D042241:Early Diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood* / Q000652:urine*; D008297:Male; D008403:Mass Screening / Q000379:methods*; D011518:Proto-Oncogene Proteins / Q000097:blood* / Q000652:urine*; D012372:ROC Curve; D014552:Urinary Tract Infections / Q000097:blood* / Q000652:urine*
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins
keywords: Neutrophil gelatinase associated lipocalin; Screening; Urinary tract infection