Clinical usefulness of cystatin C for the estimation of glomerular filtration rate in type 1 diabetes: reproducibility and accuracy compared with standard measures and iohexol clearance.

摘要: OBJECTIVE-Assessment and follow-up of early renal dysfunction is important in diabetic nephropathy. Plasma creatinine insensitive for a glomerular filtration rate (GFR) >50 ml/min clearance unwieldy subject to collection inaccuracies. We aimed assess the reproducibility, reliability, accuracy plasma cystatin C as measure GFR ranging from normal moderate impairment due type 1 diabetes presence concentration. RESEARCH DESIGN AND METHODS-A sensitive immunoturbidimetric assay was examined 29 subjects with 11 nondiabetic subjects. Duplicate measurements following were collected each subject, 2 weeks apart: C, enzymatic creatinine, 24-h clearance, estimated by Cockcroft-Gault equation, iohexol gold standard. RESULTS-Iohexol ranged 35 132 ml. min(-1). 1.73 m(-2). compared well other clinically used tests. The reliability assessed discriminant ratio, superior (3.4 vs. 1.5, P < 0.001) correlation (Rs -0.80) similar that -0.74) estimate -0.54 0.66, respectively). estimations provide an unbiased equation convert GFR. CONCLUSIONS-Based on this study, more reliable than highly correlated worthy further investigation clinical diabetes.