尿α-L-岩藻糖苷酶对糖尿病早期肾损害的诊断价值

目的探讨尿α-L-岩藻糖苷酶(AFU)测定在筛查糖尿病(DM)早期肾损害中的临床应用价值。方法将178例2型DM患者按24 h尿微量白蛋白(mAlb)排泄率分为DM无肾病组(79例)、DM早期肾病组(54例)和DM临床肾病组(45例)。应用本室建立的连续监测法检测178例2型DM患者和320名正常对照者尿AFU、mAlb、尿β2-微球蛋白(β2-MG)、N-乙酰-β-D-氨基葡萄糖苷酶(NAG)含量,并进行比较。结果采用连续监测法检测尿AFU在300 U/L以下线性良好;高、低浓度样本批内变异系数(CV)分别为1.69%、1.26%,批间CV分别为4.51%、3.52%。维生素C、胆红素和血红蛋白分别为50 mg/L、136.8μmol/L和1 g/L时对尿AFU不产生干扰。DM组尿AFU、mAlb、β2-MG、NAG分别为(2.87±0.91)U/g.Cr、(67.62±21.27)mg/g.Cr、(0.48±0.32)mg/g.Cr、(29.23±8.29)U/g.Cr,均明显高于正常对照组(0.82±0.45)U/g.Cr、(11.54±8.81)mg/g.Cr、(0.11±0.07)mg/g.Cr、(9.08±5.21)U/g.Cr](P<0.01)。DM 3个亚组之间尿AFU、mAlb、β2-MG、NAG差异均有统计学意义(P<0.01)。DM患者尿AFU与NAG呈高度正相关(r=0.859,P<0.01)。79例DM无肾病组尿AFU阳性率高达19.0%,特异性为85.7%,敏感性为91.8%,Youden指数为0.77,诊断效率89.9%。99例DM肾病患者治疗后AFU水平为(2.7±1.26)U/g.Cr,明显低于治疗前(4.6±1.72)U/g.Cr](P<0.01)。结论尿AFU测定是筛查DM早期肾损害的一项有价值的指标。

The diagnosis significance of urine alpha-L-fucosidase for diabetes mellitus early renal injury

Objective To investigate the clinical application significance of urine alpha-L-fucosidase （AFU） for screening early renal injury of diabetes mellitus （DM）. Methods The 178 type 2 DM patients were classified into DM without nephropathy group （ 79 cases ） , DM with nephropathy in early stage group （ 54 cases ） and clinical DM with nephropathy group （45 cases）, according to the 24 h urine mieroalbumin（mAlb） excretion rate. A total of 178 type 2 DM patients and 320 healthy subjects were enrolled in this study. By the continuous monitoring method established by our laboratory, the urine AFU, urine mAlb, urine beta2-microglobulin （132-MG） and N-aeetyl-beta-D-glueosaminidase （NAG） contents were detected. The results between the 2 groups were analyzed comparatively. Results The linearity of the AFU determination was up to 300 U/L. The within-run coefficients of variation （CV） of high and low AFU concentration samples were 1.69% and 1.26% respectively. The between-run CV of high and low AFU concentration samples were 4.51% and 3.52% respectively. There was no interference for urine AFU when vitamin C, bilirubin and hemoglobin were 50 rag/L, 136.8 p.mol/L and 1 g/L. Compared with the control group E （ 0.82 ±0.45 ） U/ g · Cr, （11.54±8.81）mg/ g · Cr,（0.11±0.07）mg/ g · Cr and （9.08 ±5.21）U/ g · Cr] ,the urine AFU, mAlb,β2-MG and NAG significantly increased （2.87 · O. 91 ） U/g · Cr, （67.62±21.27） rag/g · Cr, （0.48 ± 0.32） rag/g · Cr and （29.23±8.29） U/ g · Cr· in DM group （P〈0.01）. The urine AFU, mAlb, β2-MG and NAG among the 3 groups of patients with DM were statistically significant （ P 〈 O. 01 ） , and the urine AFU was positively correlated with NAG in patients with DM （r = O. 859, P 〈 0. 01 ）. In the DM without nephropathy group, the positive rate of urine AFU was 19.0% , with specificity 85.7%, sensitivity 91.8%, Youden index 0. 77 and diagnostic efficiency 89.9%. The level of urine AFU after the treatment in the DM with nephropathy group （99 cases） （ 2.7 ± 1.26 ） U/ g · Cr ] was significantly lower than that before the treatment （ 4. 6 ±1. 72 ） U/ g · Cr ] （ P 〈 0. 01 ）. Conclusions The determination of urine AFU is a valuable indicator for screening early renal injury of DM.