Table of Contents
ISRN Nephrology
Volume 2014, Article ID 430247, 16 pages
http://dx.doi.org/10.1155/2014/430247
Research Article

Proteinuria, 99mTc-DTPA Scintigraphy, Creatinine-, Cystatin- and Combined-Based Equations in the Assessment of Chronic Kidney Disease

1Servicios de Nefrología, Hospital Británico de Buenos Aires, Perdriel 74, 1280 Buenos Aires, Argentina
2Laboratorio Central, Hospital Británico de Buenos Aires, Perdriel 74, 1280 Buenos Aires, Argentina
3Servicios de Medicina Nuclear, Hospital Británico de Buenos Aires, Perdriel 74, 1280 Buenos Aires, Argentina
4Servicios de Clínica Médica, Hospital Británico de Buenos Aires, Perdriel 74, 1280 Buenos Aires, Argentina

Received 4 September 2013; Accepted 7 November 2013; Published 11 February 2014

Academic Editors: A. M. Castelao, E. F. Elsayed, and C. Escobar

Copyright © 2014 Hernán Trimarchi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. Precise estimation of the glomerular filtration rate (GFR) and the identification of markers of progression are important. We compared creatinine, cystatin, and combined CKD-EPI equations with scintigraphy to measure GFR and proteinuria as markers of progression. Methods. Cross-sectional, observational study including 300 subjects. CKD was classified by scintigraphy. Determinations. Creatinine, 24-hour creatinine clearance, cystatin, Hoek formula, and creatinine, cystatin, and combined CKD-EPI equations. Results. In the global assessment, creatinine CKD-EPI and combined CKD-EPI equations yielded the highest correlations with : ρ = 0.839, and ρ = 0.831, . Intergroup analysis versus : control G, creatinine clearance ρ = 0.414, P = 0.013; G3, combined CKD-EPI ρ = 0.5317, ; G4, Hoek ρ = 0.618, , combined CKD-EPI ρ = 0.4638, ; and G5, creatinine clearance ρ = 0.5414, , combined CKD-EPI ρ = 0.5288, . In the global assessment, proteinuria displayed the highest significant correlations with cystatin (ρ = 0.5433, ) and cystatin-based equations (Hoek: , ). When GFR < 60 mL/min: in stage 3, proteinuria-cystatin (ρ = 0.4341, ); proteinuria-Hoek (ρ = −0.4105, ); in stage 4, proteinuria-cystatin (ρ = 0.4877, ); proteinuria-Hoek (ρ = −0.4877, P = 0.0026). Conclusions. At every stage of GFR < 60 mL/min, cystatin-based equations displayed better correlations with . Proteinuria and cystatin-based equations showed strong associations and high degrees of correlation.