Division of Laboratory Medicine, Chiba University Hospital, Chiba, Japan.
Clin Chem Lab Med. 2012 Oct 1;50(10):1833-9. doi: 10.1515/cclm-2011-0777.
Diabetic nephropathy (DN) is a significant cause of hemodialysis, and its early detection is extremely important to prevent or delay end-stage renal disease. The significance of the renal function marker serum cystatin C (sCysC) and its relationship with glomerular filtration rate in chronic kidney disease (CKD) and DN in Japanese patients with type 2 diabetes remains uncertain. In this study, we examined the effectiveness of sCysC as a marker of early DN and CKD in Japanese subjects.
A total of 325 Japanese patients with type 2 diabetes and 88 healthy subjects were studied retrospectively. sCysC concentration (mg/L) was determined by a latex turbidmetric immunoassay using a BioMajesty 8040 analyzer. The renal function of the diabetic patients was evaluated using the albumin-creatinine ratio (ACR) and Kidney Disease Outcome Quality Initiative-Kidney Disease Improving Global Outcomes (K/DOQI-KDIGO) classification.
There was a significant increase in sCysC but not in serum creatinine (sCr) or serum β2-microglobulin (sβ2M) in patients with grade 2 DN (ACR 30-300 mg/g) compared to grade 1 patients. Receiver operating characteristic analysis in grade 2 and 3 DN patients showed that sCysC had superior sensitivity and specificity than sCr and sβ2M for early detection of DN. In addition, sCysC showed particularly high sensitivity and specificity in DN patients with stage 2 CKD.
sCysC was effective for detection of grade 2 DN and would be especially useful for screening stage 2 CKD patients (K/DOQI-KDIGO).
糖尿病肾病（DN）是血液透析的重要原因，早期发现对于预防或延迟终末期肾病非常重要。血清胱抑素 C（sCysC）作为肾功能标志物的意义及其与肾小球滤过率在日本 2 型糖尿病患者慢性肾脏病（CKD）和 DN 中的关系尚不确定。在这项研究中，我们研究了 sCysC 作为日本受试者早期 DN 和 CKD 的标志物的有效性。
回顾性研究了 325 例日本 2 型糖尿病患者和 88 例健康对照者。使用 BioMajesty 8040 分析仪通过乳胶比浊免疫法测定 sCysC 浓度（mg/L）。使用白蛋白-肌酐比（ACR）和肾脏病结局质量倡议-肾脏病改善全球结局（K/DOQI-KDIGO）分类评估糖尿病患者的肾功能。
与 1 级患者相比，2 级 DN（ACR 30-300mg/g）患者的 sCysC 显著升高，但血清肌酐（sCr）或血清β2-微球蛋白（sβ2M）无显著升高。在 2 级和 3 级 DN 患者中进行的受试者工作特征分析显示，sCysC 对早期检测 DN 的敏感性和特异性优于 sCr 和 sβ2M。此外，在 2 期 CKD 的 DN 患者中，sCysC 显示出特别高的敏感性和特异性。
sCysC 可有效检测 2 级 DN，对于筛选 2 期 CKD 患者（K/DOQI-KDIGO）尤其有用。
