Preliminary reference values for serum and partial urinary creatinine in Venezuelan schoolchildren aged 7 to 10 years: A descriptive cross-sectional study
DOI:
https://doi.org/10.61286/e-RPM.2025.309Keywords:
Creatinine; Reference values; Urinary excretion; Renal function; Children.Abstract
Serum and urinary creatinine are fundamental markers for assessing renal function, and their behavior in the pediatric population depends on physiological variables such as age, sex, and muscle development. In Venezuela, there is limited recent information available to establish specific reference values. This study aimed to establish preliminary reference values for serum creatinine and partial urinary creatinine in apparently healthy schoolchildren aged 7 to 10 years. A cross-sectional descriptive study was conducted in 63 children (34 females and 29 males), with measurements obtained using the kinetic Jaffé method. The data distribution was not normal according to the Shapiro-Wilk test, and non-parametric tests were applied. Serum creatinine had a mean of 0.4667 ± 0.0933 mg/dL (range: 0.30–0.70), and partial urinary creatinine had a mean of 73.825 ± 37.864 mg/dL (range: 16–164). No significant differences were found by sex for either serum creatinine (p = 0.1010) or urinary creatinine (p = 0.0579). Spearman's correlation showed a significant negative association between serum creatinine and age only in the female group (r = –0.522; p = 0.0015), with no significant correlations in the other analyses. Preliminary reference ranges, established using the 2.5th and 97.5th percentiles, were 0.30–0.64 mg/dL for serum creatinine and 16.60–153.20 mg/dL for partial urinary creatinine. These results provide a useful approximation for local clinical interpretation; however, it is recommended that the sample size be increased and that methods traceable to the IDMS be adopted to consolidate official reference ranges.References
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