胱抑素C测定在糖尿病肾病肾功能评价中的应用  

Evaluation of renal function in patients with diabetic nephropathy using cystatin C

作　　者：张培培[1] 刘志红[2] 谢红浪[2] 葛永纯[2] 李世军[2] 王生余[2] 黎磊石[2] 

机构地区：[1]南京大学医学院临床学院 [2]南京军区南京总医院解放军肾脏病研究所,南京210002

出　　处：《肾脏病与透析肾移植杂志》2007年第6期501-508,共8页Chinese Journal of Nephrology,Dialysis & Transplantation

摘　　要：目的:探讨血清胱抑素C(cystatin C,Cys-C)检测在糖尿病肾病(DN)患者肾功能评价中的诊断价值。方法:经临床及肾活检确诊的2型糖尿病、DN患者83例。免疫比浊法测定血清Cys-C浓度。同时测定血肌酐水平(SCr)、BMI数值、肾小管功能指标(NAG酶,RBP、尿渗量)、尿蛋白水平、血清白蛋白、尿酸水平、同位素99mTc-DTPA测定肾小球滤过率(GFR)。分析不同肾功能状态下Cys-C,SCr、MDRD公式与ECT-GFR的相关性。进一步根据肾小管功能指标、蛋白尿程度、血清白蛋白水平、代谢指标(血清尿酸、BMI)分组,分析Cys-C、SCr与GFR的相关性差别。以ECT-GFR为标准,作Cys-C、SCr的受试者工作特性曲线(receiver operator characteristic curve,ROC),并求其曲线下面积(area under the curve,AUC)。结果:(1)Cys-C、SCr与ECT-GFR的Pearson相关系数r分别为-0.740和-0.663(P<0.01),Cys-C与GFR的相关性较SCr更好。GFR≤60ml/min时,Cys-C、MDRD-GFR、SCr与GFR的相关系数r分别为-0.798,0.760,-0.716(P<0.01),Cys-C与GFR的相关性优于SCr和MDRD公式;GFR>90ml/min时,Cys-C、SCr与GFR的相关系数r分别为-0.561vs-0.465(P<0.05)。Cys-C与GFR的相关性优于SCr。(2)患者肾小管功能受损状态下:NAG酶>20u/g.cr时,Cys-C、SCr与GFR的相关系数r分别为-0.660vs-0.595(P<0.01);RBP>2mg/L时,r值分别为-0.672vs-0.635(P<0.01);尿渗量≤600mOsm/kg.H2O时,r值分别为-0.696vs-0.663(P<0.01)。Cys-C与GFR的相关性均较SCr更好。(3)尿蛋白>1g/24h时,Cys-C、SCr与GFR的相关系数r分别为-0.704vs-0.649(P<0.01)。血清白蛋白≤35g/L时,r值分别为-0.635vs-0.581(P<0.01)。Cys-C与GFR的相关性均较SCr更好。(4)不同血清尿酸、BMI状态下,Cys-C与GFR的相关系数r值不受影响。ROC中曲线下面积(AUC),Cys-C、SCr分别为0.915vs0.902(P<0.01),仍以Cys-C更灵敏和特异。结论:DN患者各期(包括早期高灌注期、肾功能损害期),Cys-C与GFR之间的相关性优于SCr、MDRD公式。DN患者出现肾小管功能损害时,Cys-C与GFRObjective：To evaluate the Cystatin C （Cys-C） as a marker of renal function in patients with diabetic nephropathy（DN）. Methodology：Eight three patients with DN were enrolled in this study. Serum Cys-C was tested by immunoturbidimetry, and serum creatinine （SCr） was measured at the same day. Radionuclide^99mTc-DTPA was used to evaluate glomerular fihration rate （ECT-GFR）. The tubular markers （ NAG enzyme, retinol binding protein, urine osmotic pressure）, 24-hour urine proteinuria excretion, serum albumin, and uric acid were also measured. The correlation between Cys-C, SCr, MDRD-GFR and ECT-GFR was evaluated in the different renal stages. Further more, the correlation of Cys-C and GFR was detected in different level of tubular function, proteinuria, serum albumin, uric acid and BMI. Receiver operator characteristic curve （ROC curve） of Cys-C and SCr was made by ECT-GFR as standard, and calculated the area under the curve （AUC）. Results ： （ 1 ） In the whole study population ： the Pearson correlation coefficient of Cys-C, SCr and ECT-GFR was -0. 740, -0. 663, respectively （P 〈 0. 01 ）. Cys-C correlated with GFR better than SCr. When GFR was less than 60ml/min, the correlation coefficient of Cys-C, MDRD-GFR, SCr and GFR was -0. 798, 0. 760, -0. 716, respectively （P 〈 0. 01 ）. Cys-C correlated with GFR better than SCr or MDRD formula. When GFR was more than 90 ml/min, the correlation coefficient of Cys-C, SCr and GFR was - 0. 561, - 0. 465, respectively （ P 〈 0.05）. Cys-C was also correlated with GFR better than SCr. （2）In the patients with tubular impairment： when NAG enzyme was more than 20 u/g.cr, the correlation coefficient of Cys-C, SCr and GFR was - 0. 660, - 0. 595, respectively （ P 〈 0. 01 ） ; when RBP was more than 2 mg/L, the correlation coefficient was -0. 672, -0. 635, respectively （P 〈0. 01 ） ; and when Urine osmolarity was less than 600 mOsm/kg·H2O, the correlation coefficient was -0. 696, -0. 663, respectively （ P 〈0. 01 ）

关 键 词：胱抑素C 糖尿病肾病 血肌酐 肾小管损害 蛋白尿 BMI 血尿酸 

分 类 号：R692[医药卫生—泌尿科学]