IJSRP, Volume 3, Issue 3, March 2013 Edition [ISSN 2250-3153]
Jayasekara JMKB, Dissanayake DM, Gunaratne MDN, Amunugama K
The study was aimed to evaluate whether which spot urine protein to creatinine ratio (PC) can be a reliable alternative to 24-hour urinary total protein (UTP) estimation by analyzing four day time spot urine samples of CKD clinic patients.
We studied 48 CKD patients attending Nephrology unit with different nephritis such as diabetic nephropathy, CKD due to hypertension and unknown etiology (28male and 20 female) with proteinuria over 1g/day (GFR> 45 ml/min/1.73m2) to determine the correlation between the measures of urine protein excretion by using four spot urine samples namely early morning,7am - 10 am, 10am-4pm and before going to bed. The simple linear regression, central tendency and dispersion were calculated. The Friedman test was done to evaluate difference among urine protein levels of 4 day time urine samples.
The mean 24 hour protein concentration was 3.8g/day+ 1.6 and the correlation coefficient (r) between 24-hour urine total protein and spot urine PC ratio were early morning 0.81 (P < 0.001), 7am - 10 am 0.64 (P < 0.001), 10am-4pm 0.66 (P < 0.001) and before going to bed 0.792 (P < 0.001) in the study population. Early morning spot urine sample showed the highest linear association whereas the 7am-10am and 10am-4 pm shows lower associations compared to other two spot urine samples. Highest and lowest median of PC ratio were 7 am -10am and before going to bed respectively. Highest dispersion of PC ratio was observed in 10am-4 pm and the distribution of before bed is somewhat skewed to right. We conclude that the protein-to-creatinine ratio (PC) in early morning urine sample is an accurate, convenient, and reliable method to estimate the protein excretion in urine in study population in early stages of CKD.