Faculty Collaboration Database

Improving the urine spot protein/creatinine ratio by the estimated creatinine excretion to predict proteinuria in pediatric kidney transplant recipients. Pediatr Transplant 2021 Nov;25(7):e14142

Date

09/16/2021

Pubmed ID

34523202

DOI

10.1111/petr.14142

Scopus ID

2-s2.0-85114799978 (requires institutional sign-in at Scopus site)   1 Citation

Abstract

BACKGROUND: Since the daily creatinine excretion rate (CER) is directly affected by muscle mass, which varies with age, gender, and body weight, using the spot protein/creatinine ratio (Spot P/Cr) follow-up of proteinuria may not always be accurate. Estimated creatinine excretion rate (eCER) can be calculated from spot urine samples with formulas derived from anthropometric factors. Multiplying Spot P/Cr by eCER gives the estimated protein excretion rate (ePER). We aimed to determine the most applicable equation for predicting daily CER and examine whether ePER values acquired from different equations can anticipate measured 24 h urine protein (m24 h UP) better than Spot P/Cr in pediatric kidney transplant recipients.

METHODS: This study enrolled 23 children with kidney transplantation. To estimate m24 h UP, we calculated eCER and ePER values with three formulas adapted to children (Cockcroft-Gault, Ghazali-Barratt, and Hellerstein). To evaluate the accuracy of the methods, Passing-Bablok and Bland-Altman analysis were used.

RESULTS: A statistically significant correlation was found between m24 h UP and Spot P/Cr (p < .001, r = 0.850), and the correlation was enhanced by multiplying the Spot P/Cr by the eCER equations. The average bias of the ePER formulas adjusted by the Cockcroft-Gault, Ghazali-Barratt, and Hellerstein equations were -0.067, 0.031, and 0.064 g/day, respectively, whereas the average bias of Spot P/Cr was -0.270 g/day obtained by the Bland-Altman graphics.

CONCLUSION: Using equations to estimate eCER may improve the accuracy and reduce the spot urine samples' bias in pediatric kidney transplantation recipients. Further studies in larger populations are needed for ePER reporting to be ready for clinical practice.

Author List

Incir S, Tasdemir M, Kocak B, Yelken B, Arpali E, Akyollu B, Palaoglu KE, Baygul A, Bilge I, Turkmen A

Author

Emre Arpali MD, PhD Associate Professor in the Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Biomarkers
Child
Creatinine
Female
Humans
Kidney Function Tests
Kidney Transplantation
Male
Postoperative Complications
Proteinuria