Pediatric reference values for serum creatinine and estimated glomerular filtration rate in Iranians: Tehran Lipid and Glucose Study.
BACKGROUND
Serum creatinine is the most widely used marker for estimating glomerular filtration rate (GFR). The aim of this study was to determine pediatric reference values for serum creatinine levels and eGFR values using data from a population-based study in Iran.


METHODS
Serum creatinine of 1594 subjects, aged 3 - 18 years, participating in phase 4 of the Tehran Lipid and Glucose Study (2008 - 2011) was measured using the conventional Jaffe method. The non-parametric method of Schwartz and Counahan-Barratt equations were used to calculate eGFR. CLSI/IFCC guidelines were used to determine reference values.


RESULTS
In both genders, serum creatinine concentration was significantly increased with age and had a positive correlation with age (boys (r = 0.786, n = 778, P < 0.001) and girls (r = 0.638, n = 724, P < 0.001)). In addition, mean serum creatinine concentration was significantly higher in boys, compared to girls (0.86 ± 0.01 vs. 0.80 ± 0.01 mg/dL, P < 0.001). Based on these results, we proposed the following formula: serum creatinine (mg/dL) = k × age (year) + 0.5, where k was 0.03 for boys and 0.02 for girls.


CONCLUSIONS
This study presents pediatric reference values in Iranian boys and girls for serum creatinine levels to be 0.6 - 1.20 mg/dL and 0.6 - 1.00 mg/dL and for eGFR values to be 81 - 154 mL/min/1.73 m(2) and 80 - 129 mL/min/1.73 m(2), respectively. These values can be used for diagnostic and therapeutic purposes.
Endocrine Physiology Research Center, Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Asghar
A
Ghasemi
Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Iraj
I
Azimzadeh
Endocrine Physiology Research Center, Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Marjan
M
Afghan
Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Amir Abbas
AA
Momenan
Endocrine Physiology Research Center, Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Fatemeh
F
Bagheripour
Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran. azizi@endocrine.ac.ir.
Fereidoun
F
Azizi
D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D064368:Healthy Volunteers; D006801:Humans; D007492:Iran; D007677:Kidney Function Tests; D008297:Male; D012016:Reference Values
D015415:Biomarkers; D003404:Creatinine