USE OF SINGLE VOIDED URINE SAMPLES TO ESTIMATE QUANTITATIVE PROTEINURIA IN CHILDREN

Quantitation of protein excretion in urine is used for diagnostic and prognostic purposes and also to assess the effects of therapy in child ren. The method in common use is to measure urinary protein in a 24-ho ur urine sample, which may be time consuming and is often inaccurate. The aim of this study was to determine if the urine protein/creatinine ratio in a single-void urine sample had a high correlation with the q uantity of protein in a 24-hour urine specimen. We found that there wa s an excellent correlation between the protein content of a 24-hour ur ine excretion and the protein/creatinine ratios in single morning urin e samples of 50 patients. We also discovered that a protein/creatinine ratio greater than 4.9 could signify ''nephrotic-range'' proteinuria, while a ratio less than 2.5 indicated nephritic syndrome or other ren al diseases. We concluded that the determination of urinary protein/cr eatinine concentration ratios in a single morning urine sample under m ost clinical circumstances, especially in nephrotic syndrome, could re place the measurement of protein excretion in 24-hour urine specimens.