Related Experiment Videos
Anthropometry-based reference values for 24-h urinary creatinine excretion during growth and their use in endocrine
Thomas Remer1, Annette Neubert, Christiane Maser-Gluth
1Department of Nutrition and Health, the Research Institute of Child Nutrition, Dortmund, Germany. remer@fke-do.de
Insights
New reference values for 24-hour urinary creatinine excretion in children aged 3-18 years have been established, considering anthropometric data. These values aid in assessing urine collection accuracy and estimating analyte excretion rates.
Area of Science:
- Pediatric Nephrology
- Clinical Chemistry
- Biomarker Research
Background:
- Lack of anthropometry-adjusted urinary creatinine reference values for healthy white children.
- Mandatory consideration of anthropometric data during childhood growth.
- Need for established reference ranges for accurate clinical assessment.
Purpose of the Study:
- Establish anthropometry-based reference values for 24-hour urinary creatinine excretion in healthy white children (3-18 years).
- Develop sex-specific and weight-related creatinine reference values.
- Assess the utility of these values for estimating analyte excretion and somatic protein status.
Main Methods:
- Cross-sectional study of 225 boys and 229 girls.
- Determination of anthropometric variables and 24-hour urinary creatinine excretion.
- Analysis of age and sex dependency to derive reference values.
- Validation of reference values in 40 additional children for analyte estimation.
Main Results:
- Derived sex-specific, body-weight-related creatinine reference values for age groups: 3, 4-5, 6-8, 9-13, and 14-18 years.
- Fifth percentile exceeded 0.1 mmol/kg/day in children older than 3 years.
- Reference values provided reasonable estimates for average 24-hour analyte excretion rates using spot urine samples.
- Derived ideal 24-hour creatinine excretion values for height to determine the creatinine height index.
Conclusions:
- Recommended anthropometry-based creatinine reference values as a simple tool.
- Facilitates identification of severe 24-hour urine collection errors.
- Enables calculation of average 24-hour analyte excretion rates from spot urine samples.
- Assists in assessing somatic protein status via the creatinine height index.
Background:
Urinary creatinine reference values that take anthropometric data into account, which is mandatory during growth, are not available for healthy white children.
Objective:
We sought to establish anthropometry-based reference values for 24-h urinary creatinine excretion in healthy white children aged 3-18 y.
Design:
Anthropometric variables and 24-h urinary creatinine excretion rates were determined cross-sectionally (225 boys and 229 girls). Age and sex dependency of 24-h creatinine excretion (crude and related to individual anthropometric variables) were assessed to derive appropriate creatinine reference values. The applicability of these creatinine reference values for estimation of daily excretion of certain analytes was assessed in 40 additional children.
Results:
Sex-specific, body-weight-related creatinine reference values were derived for the following age groups: 3, 4-5, 6-8, 9-13, and 14-18 y. The 5th percentile exceeded 0.1 mmol x kg(-1) x d(-1) in all age groups >3 y. The use of these creatinine reference values for estimating average 24-h excretion rates of certain analytes (determined as the ratio of analyte to creatinine in spot urine samples) yielded reasonable estimates of mean 24-h urinary excretion rates actually analyzed (spot and 24-h urine samples from the same children). Ideal 24-h creatinine excretion values for height were also derived for a potential determination of the creatinine height index.
Conclusions:
Established anthropometry-based creatinine reference values are recommended as a convenient, simple tool to 1) identify severe 24-h urine collection errors, 2) calculate average 24-h excretion rates of certain analytes (from respective ratios of analyte to creatinine) determined in spot urine samples, and 3) assess somatic protein status by determining the creatinine height index.