title: Assessment of kidney function in children by enzymatic determination of 2- or 24-h creatinine clearance: comparison with inulin clearance.
abstract: BACKGROUND
  Although renal inulin clearance (Cin) is the gold standard for evaluation of kidney function, it cannot be measured easily. Therefore, creatinine clearance (Ccr) is often used clinically to evaluate kidney function. Enzymatically measured Ccr was recently found to be much higher than Cin because of the tubular secretion of creatinine (Cr). This study compared three measures of renal clearance, inulin, 2-h Ccr, and 24-h Ccr, in children.
  
  
  METHODS
  Kidney function was evaluated in 76 children (51 males and 25 females) aged 1 month to 18 years with chronic kidney disease (CKD) by three renal clearance methods at almost the same time.
  
  
  RESULTS
  Correlations between each pair of three renal clearance measurements were determined. Approximate glomerular filtration rate (GFR) was equal to 62 % of 2-h Ccr or 76 % of 24-h Ccr.
  
  
  CONCLUSIONS
  Cr secretion by renal tubules was approximately 50 % of the GFR. In this study, we indicate that the measurements of 2-h Ccr or 24-h Ccr do not show true GFR but we could infer approximate GFR from the values. The use of 2- or 24-h Ccr might contribute to the treatment of pediatric CKD patients.
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan. o_uemura@hkg.odn.ne.jp.|Department of Clinical Medicine, Japanese Red Cross Toyota College of Nursing, 12-33 Nanamagari, Hakusan-cho, Toyota, Aichi, 471-8565, Japan. o_uemura@hkg.odn.ne.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Uemura
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Takuhito
authors.initials: T
authors.lastname: Nagai
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamakawa
authors.affiliation: Department of Clinical Research, Tokyo Metropolitan Children's Medical Center, 2-8-29 Musashidai, Fuchu, Tokyo, 183-8561, Japan.
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Kaneko
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Hibi
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Yamasaki
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Nakano
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Iwata
authors.affiliation: Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, 426 7-chome, Morioka-cho, Obu, Aichi, 474-8710, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hibino
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000097:blood / Q000652:urine; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007223:Infant; D007444:Inulin / Q000008:administration & dosage*; D007564:Japan; D007668:Kidney / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D008954:Models, Biological; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors; D016482:Urinalysis; D014564:Urogenital Abnormalities / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology / Q000652:urine; D014718:Vesico-Ureteral Reflux / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology / Q000652:urine
chemical_list: D015415:Biomarkers; D007444:Inulin; D003404:Creatinine
keywords: 2-h creatinine clearance; 24-h creatinine clearance; Chronic kidney disease; Glomerular filtration rate; Inulin clearance