Spot Urinary Citrate Normograms in Children.

Citrate in the urine inhibits nephrolithiasis, and oral citrate solutions are used to prevent stones forming. The present study aimed to estimate the normograms of the urinary levels of citrate, creatinine, and their ratio in spot urine samples collected from 237 healthy children, aged from 1 month to 14 years. The findings showed the mean, standard deviation, median, and 5th and 95th percentiles of the values and compared them among age groups and between the sexes by using analysis of variance and independent t-tests. Our findings indicate that the ratio of spot urinary citrate to creatinine was higher for children younger than 18 months of age, possibly related to the consumption of dairy protein as their main meal. The 5th percentiles (lower cut off) for spot urinary citrate-to-creatinine ratio, were 915 mg/g for children aged under 18 months, 109 mg/g and 126 mg/g for older boys and girls.