Quantitative Evaluation of Proteinuria by Estimation of the Protein/Creatinine Ratio in a Random Urine Sample

Abstract

The aim of this study was to evaluate the severity of proteinuria using the protein/creatinine ratio in a random urine sample. In 45 patients (male 28, female 17; mean age 50.68 +/- 18.26 years) with proteinuria of various causes, we measured the 24-hour protein excretion per 1.73 m(2) of body surface and, during the same day, the protein/creatinine ratio in three different urine samples (8 am, 12 pm, 4 pm). The 24 h proteinuria was defined as mild (<1 g), moderate (1-3.4 g), and severe (>3.4 g) in 7, 27, and 11 patients, respectively. The sensitivity for protein/creatinine ratio compared to the 24 h proteinuria as a method of reference was 86-100% in the mild, 78-100% in the moderate, and 73-82% in the severe proteinuria, whereas the specificity was 84-100%, 78-83%, and 100% respectively. The patients with better renal function had significantly higher proteinuria levels. There was a similarity in the 24 h proteinuria and the protein/creatinine ratio measurements in all renal function and level-of-proteinuria groups. The protein/creatinine ratio of the morning and midday samples had a very good association with the 24 h sample, whereas it was not associated significantly with the evening sample (4 pm). In conclusion, the degree of 24 h proteinuria levels can be evaluated by calculating the protein/creatinine ratio in a random urine sample collected at any time from morning until midday. Protein/creatinine ratio is independent of the severity of proteinuria or renal function, and it can replace in clinical practice the cumbersome 24 h urine collections.

Reference values of urine protein/creatinine ratio in healthy Dalian adults

“…The eGFR was calculated using the 2009 CKD‐EPI equation. Similar to the findings of Kosmadakis et al, 23 we found that a high eGFR corresponded to a lower median and 95th percentile of UPCR. In addition, we found that women had significantly higher UPCR than men did in the normal eGFR group (eGFR≥90 ml/min/1.73 m 2 ).…”

Recent Advances in Biosensor Technologies for Point-of-Care Urinalysis

“…With respect to sensitivity, the dipstick test—as a point-of-care (POC) diagnostic—is only intended for qualitative detection in situations where accurate measurements of analytes at extremely low concentrations are not as critical. For instance, the dipstick test for proteinuria and hematuria is useful in screening for chronic kidney disease (CKD); however, quantitative methods based on measurement of the urine creatinine concentration are considered to be more effective to assess the severity of proteinuria [ 22 , 23 , 24 ]. In addition, because the dipstick test is entirely dependent on colorimetry, reflected visually by a color change on the reagent pads, only semi-quantitative analysis is available, where the results provide only an estimate of the amount of substance present [ 25 ].…”

Effects of the hydrophilic extract of Juniperus excelsa on renal function in male Wistar rats

“…The functioning of the kidney and urinary tract is essential for the maintenance of life. The primary function of the kidneys and urinary tract is the excretion of waste materials, preservation of homeostasis by regulating body fluids and electrolytes and promoting erythropoiesis (1)(2)(3)(4)(5)(6). Herbal plants including the Ores plant (Juniperus excelsa) has been used for a long-time to treat and prevent urinary tract and kidney diseases (7-9).…”