Comparison of spot urine protein creatinine ratio with 24 hour urine protein for estimation of proteinuria.

The objective of our study was to evaluate and standardise the method of spot (random) urine protein creatinine ratio (UP/C) for estimation of proteinuria. The study contained 241 study participants in a tertiary care hospital inclusive of 208 cases and 33 normal volunteers. The 24 hour urine protein estimation was done on 24 hour urine samples and UP/C ratio was calculated on random urine samples. UP/C ratio and 24 hour urine protein estimation had strong correlation with r = 0.9 and p < 0.05 on Pearson's correlation analysis. Receiver operating characteristic analysis showed random UP/C ratio of 0.1171 reliably predicted 24 hour urine total protein equivalent of > 150 mg/24 hrs with sensitivity 100%, specificity 98.1%, positive likelihood ratio 53.5, and negative likelihood ratio 0. UP/C ratio of 3.2 reliably predicted nephrotic range proteinuria at 24 hour urine protein equivalent of > 3.5 g/24 hrs with sensitivity 80%, specificity 100%, positive likelihood ratio 154.4, and negative likelihood ratio 0.2. We conclude that spot/random UP/C ratio is a reliable, simple test to be introduced and adopted in routine practice for monitoring of macro proteinuria.