All issues > Volume 29(7); 1986

Original Article

J Korean Pediatr Soc. 1986;29(7):723-729. Published online July 31, 1986.

Estimation of Glomerular Filtration Rate from Plasma Creatinine and Height in Premature and Fullterm Neonates.

Yeong Jee Kim¹, Keun Lee¹

¹Department of Pediatrics, College of Medicine，Ewha Womans University

Abstract

In clinical practice, creatinine clearance(Ccr) remains the most commonly used laboratory assessment of glomerular function despite methodological and technical problems of urine collection. Schwartz et al. in 1976，reported that an accurate estimate of glomerular filtration rate (GFR) could be obtained from the simple determinations of plasma creatinine (Per) and body length(L):GFR(ml/min/1.73cm2)=k• L(cm)/Pcr(mg/100ml), (k=constant). The purpose of this investigation is to compare neonatal GFR estimated by Ccr with that calculated by the formula： GFR=k• L/Pcr,(k=constant). The subjects of this study were 17 premature and 22 fullterm male neonates admitted to our nursery without any medical or renal problem. The concentration of creatinine has been measured by Jaffe reaction. The constant 0.55 derived from Zacchello(1982) was used for the formula: GFR=k • L/Pcr, (k=constant) to compare with Ccr. The result obtained show; 1) For premature neonates«gestational age 34 weeks), the correlation between 24hour Ccr determinations(average value: 15.73±5.25 ml/min/1.73 m2) and GFR estimated by the formula： 0.55*L/Pcr(average value: 21.03±5.50 ml/min/1.73m2) is statistically not significant. 2) For premature neonates (gestational age 34 〜 36 weeks), the correlation between 24 hour Ccr determinations (average value: 26.52±6.95 ml/min/1.73 m2) and GFR estimated by the formula： 0.55*L/Pcr(average value: 22.42±6.71 ml/min/1.73 m2) is statistically not significant. 3) For fullterm neonates (gestational age 37^42 weeks), the correlation between 24 hour Ccr determinations (average value: 32.72±11.20 ml/min/1.73 m2) and GFR estimated by the formula： 0.55*L/Pcr(average value: 36.38±11.78ml/min/1.73 m2) is highly significant(r=0.65, P<0.001). 4) The constant 0.55 derived from Zacchello(1982) for the formula： GFR=k«L/Pcr, is appropriate for fullterm neonte, but cannot be used for premature neonates. The values for k derived from our data are 0.43 for premature neonate«gestational age 34 weeks), 0.71 for premature neonate (gestational a谷e 34〜36 weeks) and 0.55 for fullterm neonate (gestational age 37〜42 week).

Keywords :Height;Plasma creatinine; Glomerular filtration rate