Quantitation of proteinuria by the use of protein-to-creatinine ratios in random urine samples

Abstract

Measurements of protein-to-creatinine ratios (U^p/Cr) in simple voided urine samples were compared with 24-hour urinary protein excretions in order to guantify proteinuria in inpatients and outpatients. A highly significant linear correlation (r=0 .73), was observed between the two variables. A closer correlation was found in the urine samples obtained from outpatients with non-nephrotic syndrome and normal renal function. Furthermore, in the investigation of urine samples from inpatients, there was a significant correlation between the two variables in urine obtained during the morning, but neither in the early morning nor at night. However, there was no significant correlation between males and females. The results of our study indicate that U^p/Cr in urine samples obtained during the morning provides an accurate quantitative estimate of protein excretion . Furthermore, in clinical practice, this is a suitable method of quantifying proteinuria in patients with renal diseases, particularly, non-nephrotic syndrome and normal renal function.