Proteinuria in health and disease assessed by measuring the urinary protein/creatinine ratio.
We measured daily excretion rates for urinary protein and the ratios of urinary protein to creatinine in 24-h urines and in untimed urines in 60 healthy adults, 30 patients with kidney disease, and 22 kidney-transplant recipients. The ratios for urinary protein/creatinine, mg/g, in untimed urines and in 24-h urines from the same subjects were closely correlated (r = 0.97) for rates of protein excretion ranging from normal (mean 44 mg/day) to nephrotic (maximum 19,300 mg/day). Because urinary protein/creatinine in healthy subjects never exceeded 100 mg/g, we propose that a ratio of less than 100 mg/g in untimed urines, obtained in the absence of exercise, fever, or other evidence of urinary tract disease, is a criterion of normal kidney function. Among patients with nephrotic syndrome (urinary protein excretion rate greater than or equal to 4000 mg/day), urinary protein/creatinine ratios always exceeded 2000 mg/g in both 24-h and untimed urines. Intermediate urinary protein/creatinine ratios (100 to 2000 mg/g) may reflect any type of kidney disease.
D003404:Creatinine / Q000652:urine*; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000601:surgery / Q000652:urine*; D016030:Kidney Transplantation; D008297:Male; D009404:Nephrotic Syndrome / Q000652:urine; D011507:Proteinuria / Q000652:urine*; D012016:Reference Values; D013223:Statistics as Topic
D003404:Creatinine