Ha S K, Park C H, Seo J K, Park S H, Kang S W, Choi K H, Lee H Y, Han D S
Department of Internal Medicine, Yongdong Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
Yonsei Med J. 1996 Oct;37(5):350-6. doi: 10.3349/ymj.1996.37.5.350.
Renal osteodystrophy has become a frequent complication in patients with chronic renal failure (CRF), and various histologic forms such as high turnover, low turnover and mixed bone disease have been demonstrated. The only reliable method for distinguishing patients with high turnover from those with low turnover bone disease is bone histomorphometric study, but its clinical utility is restricted. Because of its invasive nature, efforts have been made to predict indirectly the type and severity of this metabolic bone disease by serum assays. In this cross-sectional study, we measured total and regional (head, arms, trunk, ribs, legs, spine and pelvis) bone mineral densities (BMD) by dual X-ray absorptiometry (DXA) in patients with variable degrees of CRF and correlated them with various bone markers. Decreased BMDs were detected in various skeletal sites (trunk and pelvis) in the patients' group. Total BMD Z score was lower in predialysis CRF patients than in the control subjects. Decreased BMD Z scores on weight-bearing bone were pronounced at L1 lumbar vertebra, femur trochanter, femur neck and Ward's triangle. Positive linear correlations were found between creatinine clearance and trunk, ribs, pelvis, and spine BMDs. There were inverse linear correlations between total BMD and total BMD Z score and alkaline phosphatase (AP), urine deoxypyridinoline (U-DPD) in the patients' group. There were no correlations between regional and total BMD, total BMD Z score and serum calcium, ionized calcium, and serum phosphate. There were inverse linear correlations between BUN, creatinine and bone-specific alkaline phosphatase in the predialysis CRF group. We evaluated the correlations between intact parathyroid hormone (i-PTH) and biochemical and other bone markers. There was statistically significant linear correlation between i-PTH and AP. Other bone markers have no significant correlations with i-PTH. Our results demonstrated that there is significant bone loss in patients with CRF before the start of dialysis and also regional variations of BMDs in predialysis CRF patients. DXA is a useful method for evaluating regional and total BMDs and provides information about diverse regional skeletal changes. AP, i-PTH and U-DPD can predict BMD of predialysis CRF patients.
肾性骨营养不良已成为慢性肾衰竭（CRF）患者常见的并发症，并且已证实存在多种组织学形式，如高转换型、低转换型和混合型骨病。区分高转换型患者与低转换型骨病患者的唯一可靠方法是骨组织形态计量学研究，但其临床应用受到限制。由于其侵入性，人们一直在努力通过血清检测间接预测这种代谢性骨病的类型和严重程度。在这项横断面研究中，我们采用双能X线吸收法（DXA）测量了不同程度CRF患者的全身及局部（头部、手臂、躯干、肋骨、腿部、脊柱和骨盆）骨密度（BMD），并将其与各种骨标志物进行关联分析。在患者组中，多个骨骼部位（躯干和骨盆）检测到骨密度降低。透析前CRF患者的全身BMD Z评分低于对照组。负重骨的BMD Z评分在第1腰椎、股骨转子、股骨颈和Ward三角区明显降低。肌酐清除率与躯干、肋骨、骨盆和脊柱的BMD之间存在正线性相关。在患者组中，全身BMD和全身BMD Z评分与碱性磷酸酶（AP）、尿脱氧吡啶啉（U-DPD）之间存在负线性相关。局部和全身BMD、全身BMD Z评分与血清钙、离子钙和血清磷之间无相关性。在透析前CRF组中，血尿素氮、肌酐与骨特异性碱性磷酸酶之间存在负线性相关。我们评估了完整甲状旁腺激素（i-PTH）与生化及其他骨标志物之间的相关性。i-PTH与AP之间存在统计学显著的线性相关。其他骨标志物与i-PTH无显著相关性。我们的结果表明，透析开始前CRF患者存在明显的骨质流失，且透析前CRF患者的BMD也存在局部差异。DXA是评估局部和全身BMD的有用方法，并可提供有关不同局部骨骼变化的信息。AP、i-PTH和U-DPD可预测透析前CRF患者的BMD。
