Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, China.
Nephrology (Carlton). 2011 Aug;16(6):588-94. doi: 10.1111/j.1440-1797.2011.01481.x.
Chronic kidney disease-mineral and bone disorder (CKD-MBD) has been proposed to be the replacement of renal osteodystrophy by the Organization of Kidney Disease: Improving Global Outcomes since 2005 because the mineral disorder is not confined to the skeleton in CKD. Accordingly, laboratory and imaging tests have been emphasized for the clinical assessment of patients with CKD besides renal biopsy. The objective of the current study was to investigate whether osteoprotegerin (OPG) could be made a useful biomarker for early diagnosis of CKD-MBD.
Sixty pre-dialysis patients with CKD 1-5 were enrolled in this study. The serum calcium, phosphorus, blood urea nitrogen, creatinine, alkaline phosphatase, Osteocalcin, Calcitonin, intact parathyroid hormone and OPG were measured. Bone mineral densities of the lumbar spine (L2-L4), femoral neck, Ward's triangle and trochanter were measured by dual-energy X-ray absorptiometry.
Among all measured serum bone metabolism indexes, the changing of serum OPG level happened at the earliest time (CKD 3) and its correlation coefficient with estimated glomerular filtration rate (eGFR) was also the highest (r = -0.601, P = 0.001). In the multivariable analysis that included sex, age and eGFR as controlling factors, the serum OPG correlated with the bone mineral density (BMD) of Ward's triangle (r = -0.390, P = 0.041).
Serum OPG may be a useful biomarker for early diagnosis of CKD-MBD.
自 2005 年以来，肾脏病：改善全球预后组织（Kidney Disease: Improving Global Outcomes，KDIGO）提出用慢性肾脏病-矿物质和骨异常（Chronic kidney disease-mineral and bone disorder，CKD-MBD）取代肾性骨营养不良，因为矿物质异常并不仅局限于 CKD 患者的骨骼。因此，除了肾活检外，实验室和影像学检查也被强调用于 CKD 患者的临床评估。本研究旨在探讨骨保护素（Osteoprotegerin，OPG）是否可作为 CKD-MBD 早期诊断的有用生物标志物。
本研究纳入了 60 名 1-5 期的未透析 CKD 患者。检测了血清钙、磷、尿素氮、肌酐、碱性磷酸酶、骨钙素、降钙素、全段甲状旁腺激素和 OPG。采用双能 X 线吸收法检测了腰椎（L2-L4）、股骨颈、Ward 三角和转子间的骨矿物质密度。
在所有检测的血清骨代谢指标中，血清 OPG 水平的变化最早出现（CKD 3 期），其与估算肾小球滤过率（estimated glomerular filtration rate，eGFR）的相关系数也最高（r = -0.601，P = 0.001）。在包含性别、年龄和 eGFR 作为控制因素的多变量分析中，血清 OPG 与 Ward 三角的骨矿物质密度（bone mineral density，BMD）相关（r = -0.390，P = 0.041）。
血清 OPG 可能是 CKD-MBD 早期诊断的有用生物标志物。
