Ylinen E A, Ala-Houhala M, Harmoinen A P, Knip M
Medical School, University of Tampere, Finland.
Pediatr Nephrol. 1999 Aug;13(6):506-9. doi: 10.1007/s004670050647.
Cystatin C is a non-glycated 13-kilodalton basic protein produced by all nucleated cells. The low molecular mass and the basic nature of cystatin C, in combination with its stable production rate, suggest that the glomerular filtration rate (GFR) is the major determinant of cystatin C concentration in the peripheral circulation. Recently published studies have shown that cystatin C correlates more strongly than creatinine with GFR measured using the 51Cr-EDTA clearance. The aim of this study was to evaluate serum cystatin C as a marker for GFR in children. GFR was determined on medical indications using the 51Cr-EDTA technique in pediatric patients (2-16 years) in our renal unit. Simultaneously their cystatin C and creatinine concentrations were also measured. Of our 52 patients, 19 had a reduced renal function (<GFR 89 ml/min per 1.73 m2) based on the 51Cr-EDTA clearance. The correlation of cystatin C with the isotopic measurement of GFR tended to be stronger (r=0.89, P=0.073) than that of creatinine (r=0.80). Receiver operating characteristic analysis showed that the diagnostic accuracy of cystatin C was better (P=0.037) than that of creatinine in discriminating between subjects with normal renal function and those with reduced GFR. This study demonstrates that serum cystatin C has an increased diagnostic accuracy for reduced GFR when compared with serum creatinine. Hence, cystatin C seems to be an attractive alternative for the estimation of GFR in children.
胱抑素C是一种由所有有核细胞产生的非糖化的13千道尔顿碱性蛋白。胱抑素C的低分子量和碱性性质，再加上其稳定的产生速率，表明肾小球滤过率（GFR）是外周循环中胱抑素C浓度的主要决定因素。最近发表的研究表明，与肌酐相比，胱抑素C与使用51Cr - EDTA清除率测量的GFR的相关性更强。本研究的目的是评估血清胱抑素C作为儿童GFR标志物的情况。在我们肾脏科，根据医学指征，采用51Cr - EDTA技术测定了儿科患者（2至16岁）的GFR。同时还测量了他们的胱抑素C和肌酐浓度。在我们的52例患者中，根据51Cr - EDTA清除率，有19例肾功能降低（<GFR 89 ml/min per 1.73 m2）。胱抑素C与GFR同位素测量值的相关性（r = 0.89，P = 0.073）往往比肌酐（r = 0.80）更强。受试者工作特征分析表明，在区分肾功能正常和GFR降低的受试者时，胱抑素C的诊断准确性（P = 0.037）优于肌酐。本研究表明，与血清肌酐相比，血清胱抑素C对降低的GFR具有更高的诊断准确性。因此，胱抑素C似乎是评估儿童GFR的一个有吸引力的替代指标。
