Urinary protein/creatinine ratio can be used to evaluate proteinuria in children

Urinary protein/creatinine ratio (UPCR) can be used to evaluate proteinuria, according to a study, although the degree of proteinuria, 24-hour urine creatinine, and renal disease type make influence the correlation between UPCR and 24-hour urine protein (24hUP) in children with nephrotic-range proteinuria.

This study included 149 with non-nephrotic-range proteinuria and 207 with nephrotic-range proteinuria, which was divided by Henoch-Schönlein purpura nephritis (HSPN), lupus nephritis (LN), and primary nephrotic syndrome (PNS).

There was excellent agreement between UPCR and 24hUP for each of the groups, with strong correlations in all children (n = 356) and children in the non-nephrotic-range proteinuria group and moderate correlations in children in the nephrotic-range proteinuria group.

Increases in nephrotic-range proteinuria led to decreases between UPCR and 24hUP; the correlation coefficient was improved after UPCR was adjusted by 24-h urine creatinine.

Amongst the nephrotic-range proteinuria subgroups, HSPN had a high correlation coefficient, but LN and PNS did not. The sensitivity of UPCR for diagnosing nephrotic-range proteinuria was 89.9 % while the specificity was 92.2%.

Reference
Zhai P, Huang Y, Yue S, et al. Diagnostic efficacy and influence factors of urinary protein/creatinine ratio replacing 24-h urine protein as an evaluator of proteinuria in children. Int Urol Nephrol. 2021;doi: 10.1007/s11255-021-03021-3. Epub ahead of print. PMID: 34668110.