Paired measurement of urinary creatinine in neonates based on a Jaffe and an enzymatic IDMS-traceable assay

BMC Nephrology

Steven Pauwels¹  Elena Levtchenko²  Djalila Mekahli²  Anne Smits³  Pieter Vermeersch¹  Karel Allegaert³ 

[1] Department of cardiovascular sciences, KU Leuven, Belgium;Department of Paediatric Nephrology, University Hospitals Leuven, Leuven, Belgium;Department of Development and Regeneration, KU Leuven, Belgium

关键词: IDMS traceable;    Enzymatic;    Jaffe;    Newborn;    Urinary creatinine;   

Others  :  1082700
DOI  :  10.1186/1471-2369-15-62

 received in 2013-12-04, accepted in 2014-04-09,  发布年份 2014

【 摘 要 】

Background

Urinary creatinine can be quantified by Jaffe or enzymatic assays and is commonly used as denominator of urinary excretion of electrolytes or protein. Paired analysis in pediatric and adult samples documented inter-assay differences (up to 80%). We verified the interchangeability of two IDMS-traceable assays (Jaffe and enzymatic) for neonatal urine and report on neonatal urinary creatinine values using these IDMS-traceable methods.

Methods

Creatinine was measured in 84 neonatal urine samples from 46 neonates by an IDMS traceable Jaffe and enzymatic assay (Roche Diagnostics, Cobas c702 module). Creatinine values, differences in urinary creatinine and clinical characteristics were described and covariates of between assay difference were explored (Wilcoxon, Bland-Altman, correlation, multiple regression).

Results

Median Jaffe and enzymatic urinary creatinine concentrations were 9.25 (range 3.7-42.2) and 9.15 (range 3.8-42.9) mg/dL respectively, resulting in a median difference of 0.08 (SD 0.6, range −2.4 to 0.96) mg/dL. In a multiple regression model, urinary enzymatic creatinine concentration (r = 0.45) and postnatal age (r = −0.59) remained independent variables of the difference between both assays (r² adj = 0.45).

Conclusions

The tested IDMS-traceable assays showed interchangeable in heterogeneous neonatal urine samples. Using these assays, neonatal urinary creatinine showed 5–20 fold lower values than those observed in children or adults with a significant negative correlation with postnatal age.

【 授权许可】

   
2014 Allegaert et al.; licensee BioMed Central Ltd.

【 图 表 】

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【 参考文献 】

• [1]Vieux R, Hascoet JM, Merdariu D, Fresson J, Guillemin F: Glomerular filtration rate reference values in very preterm infants. Pediatrics 2010, 125:e1186-e1192.
• [2]Sonntag J, Prankel B, Waltz S: Serum creatinine concentration, urinary creatinine excretion and creatinine clearance during the first 9 weeks in preterm infants with a birth weight below 1500 g. Eur J Pediatr 1996, 155:815-819.
• [3]Srivastava T, Alon US, Althahabi R, Garg U: Impact of standardization of creatinine methodology on the assessment of glomerular filtration rate in children. Pediatr Res 2008, 65:113-117.
• [4]Van Lente F, Suit P: Assessment of renal function by serum creatinine and creatinine clearance: glomerular filtration rate estimated by four procedures. Clin Chem 1989, 35:2326-2330.
• [5]Junge W, Wilke B, Halabi A, Klein G: Determination of reference intervals for serum creatinine, creatinine excretion and creatinine clearance with an enzymatic and a modified Jaffé method. Clin Chim Acta 2004, 344:137-148.
• [6]Smits A, Kulo A, de Hoon JN, Allegaert K: Pharmacokinetics of drugs in neonates: pattern recognition beyond compound specific observations. Curr Pharm Des 2012, 18:3119-3146.
• [7]Peake M, Whiting M: Measurement of serum creatinine – current status and future goals. Clin Biochem Rev 2006, 27:173-184.
• [8]Myers GL, Miller WG, Coresh J, Fleming J, Greenberg N, Greene T, Hostetter T, Levey AS, Panteghini M, Welch M, Eckfeldt JH, National Kidney Disease Education Program Laboratory Working Group: Recommendations for improving serum creatinine measurement: a report from the Laboratory Working Group of the National Kidney Disease Education Program. Clin Chem 2006, 52:5-18.
• [9]U.S. department of Health and Human Services: About NKDEP. Available at: http://nkdep.nih.gov/about-nkdep/working-groups/laboratory-working-group.shtml webcite. Accessed Dec 2, 2013
• [10]Apple F, Bandt C, Prosch A, Erlandson G, Holmstrom V, Scholen J, Googins M: Creatinine clearance: enzymatic vs Jaffé determinations of creatinine in plasma and urine. Clin Chem 1986, 32:388-390.
• [11]Allegaert K, Palmer GM, Anderson BJ: The pharmacokinetics of intravenous paracetamol in neonates: size matters most. Arch Dis Child 2011, 96:575-580.
• [12]Decock RF, Allegaert K, Vanhaesebrouck S, de Hoon J, Verbesselt R, Danhof M, Knibbe CA: Low contribution of renal elimination to clearance of propylene glycol in preterm and term neonates. Ther Drug Monit 2014. doi:10.1097/FTD.0000000000000003
• [13]Roche Diagnostics: Roche Creatinine plus Ver.2, package insert 2011-03, V4. Mannheim: Roche Diagnostics GmbH; 2011.
• [14]Roche Diagnostics: Roche Creatinine Jaffé Gen.2, package insert 2011-11, V7. Mannheim: Roche Diagnostics GmbH; 2011.
• [15]Westgard J: Desirable Biological Variation Database specifications. 2009. http://www.westgard.com/biodatabase1.htm webcite (accessed February 2014)