title: Serum NGAL, cystatin C and urinary NAG measurements for early diagnosis of contrast-induced nephropathy in children.
abstract: OBJECTIVE
  The study investigated a number of biomarkers for the early diagnosis of contrast-induced nephropathy (CIN), which is an important cause of acute kidney injury (AKI).
  
  
  METHODS
  The study included 91 children scheduled for elective cardiac angiography and 50 healthy controls. Biomarkers including serum (s) and urinary (u) sodium, serum and u-creatinine, s-cystatin-C, serum neutrophil gelatinase-associated lipocalin (NGAL) and urinary N-acetyl beta glucosaminidase (u-NAG)/creatinine ratio were measured 4 times sequentially in the patients and once in the controls.
  
  
  RESULTS
  The patient group comprised 40 males (44%) and 51 females (56%) while the control group comprised 16 males (32%) and 34 females (68%). Age, gender, s-creatinine, estimated-glomerular filtration rate (eGFR), s-cystatin-C and fractional-excretion of sodium did not differ significantly between the groups. Serum sodium and s-NGAL were found to be lower in the patients than those of in the controls, while their u-NAG/creatinine ratio was found to be higher. Sequential data analysis revealed that s-NGAL and u-NAG/creatinine ratio increased in the first 6 h after radiocontrast media (RCM) administration and decreased at 12 and 24 h. Serum BUN and s-cystatin-C levels also showed a significant difference during the 24-h follow-up. eGFR, s-sodium and s-creatinine levels did not change in the following period. Serum cystatin-C levels revealed a significant negative correlation with eGFR. Administered RCM doses showed a positive correlation only with u-NAG/creatinine ratios.
  
  
  CONCLUSIONS
  In the first 24 h, s-cystatin-C, s-NGAL and especially u-NAG/creatinine ratio showed promise as biomarkers, but eGFR is not adequate for early diagnosis of CIN. Sequential measurement of biomarkers may contribute to more accurate diagnosis of AKI.
authors.affiliation: a Department of Pediatric Nephrology , Marmara University Medical Faculty , Istanbul , Turkey .
authors.forename: Meryem
authors.initials: M
authors.lastname: Benzer
authors.affiliation: a Department of Pediatric Nephrology , Marmara University Medical Faculty , Istanbul , Turkey .
authors.forename: Harika
authors.initials: H
authors.lastname: Alpay
authors.affiliation: b Department of Biochemistry , Marmara University Medical Faculty , Istanbul , Turkey , and.
authors.forename: Özgür
authors.initials: Ö
authors.lastname: Baykan
authors.affiliation: c Department of Pediatric Cardiology , Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Center and Research Hospital , Istanbul , Turkey.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Erdem
authors.affiliation: c Department of Pediatric Cardiology , Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Center and Research Hospital , Istanbul , Turkey.
authors.forename: Ibrahim Halil
authors.initials: IH
authors.lastname: Demir
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine*; D000293:Adolescent; D015415:Biomarkers / Q000097:blood / Q000652:urine; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D055316:Cystatin C / Q000097:blood*; D005260:Female; D006801:Humans; D000071068:Lipocalin-2 / Q000097:blood*; D008297:Male; D051437:Renal Insufficiency / Q000097:blood / Q000139:chemically induced* / Q000175:diagnosis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D055316:Cystatin C; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D000118:Acetylglucosaminidase
keywords: Acute kidney injury; N-acetyl beta glucosaminidase; contrast-induced nephropathy; cystatin C; neutrophil gelatinase-associated lipocalin