Comparison between spot urine and overnight urine in the estimation of 24-hour excretion of urine protein, sodium and kallikrein.
To compare the value of spot urine and overnight 9-hour urine in the estimation of 24-hour urinary sodium excretion (UNaV), protein excretion (UpV) and kallikrein excretion (UKaV), we measured the concentration of sodium, protein, kallikrein and creatinine in spot urine, overnight 9-hour urine, and 24-hour urine samples obtained from 21 patients with various renal diseases. They ranged in age from 16 to 75 years with 10 males and 11 females. Urinary protein was measured by the Coomassie Blue dye-binding method. Urinary kallikrein activity was measured by assay of its amidase activity on synthetic substrate S-2266. The results showed that the 9-hour UpV and 9-hour urine P/Cr ratio was better correlated with the 24-hour UpV than the spot urine P/Cr ratio (at 9-11 AM), and the 9-hour UKaV and spot urine Ka/Cr ratio were better correlated with the 24-hour UKaV than the 9-hour Ka/Cr ratio. Only the 9-hour UNaV was correlated with the 24-hour UNaV. We conclude that overnight 9-hour urine, in view of its lower cost, equal effectiveness and convenience, is the best method to substitute for 24-hour urine collection in the evaluation of Na, P and Ka excretion in patients with renal diseases.
Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei, R.O.C.
T J
TJ
Tsai
Y M
YM
Chen
B S
BS
Hsieh
W Y
WY
Chen
D000293:Adolescent; D000328:Adult; D000368:Aged; D003404:Creatinine / Q000652:urine; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007610:Kallikreins / Q000652:urine*; D008297:Male; D008875:Middle Aged; D011507:Proteinuria / Q000652:urine*; D012964:Sodium / Q000652:urine*; D013048:Specimen Handling / Q000379:methods*; D013997:Time Factors
D012964:Sodium; D003404:Creatinine; D007610:Kallikreins