Thode J, Finnerup B, Parvin C, Holmegaard S N, Skaarup P, Sørensen O H, Transbøl I
Division of Laboratory Medicine, Washington University School of Medicine, St. Louis, Mo.
Miner Electrolyte Metab. 1988;14(5):288-96.
Groups comprising 42 recurrent and 38 single calcium stone formers, and 48 controls underwent a standardized study protocol. During 12 h of fasting along with a standardized water load urine was collected for the last 4 h. One blood sample was drawn midway during urine collection. As compared with controls recurrent stone formers demonstrated significantly raised values of plasma ionized calcium, 1,25-dihydroxyvitamin D [1,25-(OH)2D], urinary ionized calcium, urinary pH, and standardized excretion rate of calcium [ECa(U)]. The tubular reabsorption of sodium and chloride, the maximal tubular reabsorption of phosphate, nephrogenous cyclic AMP (NcAMP), glomerular filtration rate (GFR) and plasma albumin were all significantly depressed. Data from the single stone former group were intermediate between controls and recurrent stone formers. For the pathogenesis of recurrent calcium stone formation these data suggest a general, though variably expressed, defect in the proximal tubular reabsorption of calcium, phosphate, bicarbonate, sodium and chloride leading to hypersecretion of 1,25-(OH)2D, hyperabsorption of calcium from the gut and a modest increase in plasma ionized calcium. Computer analysis of data do not support the concept that stone patients can be classified as either intestinal hyperabsorbers or renal losers. A stepwise discriminant analysis selected plasma albumin, urinary pH, ECa(U), plasma phosphate, GFR and NcAMP as the most important variables contributing to the difference between controls and recurrent stone formers. By this procedure we obtain a sensitivity of 93% and a specificity of 96% respecting proper classification of the recurrent stone former. The analysis may therefore be of value predicting the risk of recurrent stone formation in the single stone former.
42名复发性钙结石患者、38名单发性钙结石患者和48名对照者组成的小组接受了标准化研究方案。在禁食12小时并给予标准化水负荷的情况下，在最后4小时收集尿液。在尿液收集过程中间抽取一份血样。与对照者相比，复发性结石患者的血浆离子钙、1,25-二羟维生素D [1,25-(OH)₂D]、尿离子钙、尿pH值和钙的标准化排泄率[ECa(U)]值显著升高。钠和氯的肾小管重吸收、磷酸盐的最大肾小管重吸收、肾源性环磷酸腺苷(NcAMP)、肾小球滤过率(GFR)和血浆白蛋白均显著降低。单发性结石患者组的数据介于对照者和复发性结石患者之间。对于复发性钙结石形成的发病机制，这些数据表明近端肾小管对钙、磷酸盐、碳酸氢盐、钠和氯的重吸收存在普遍但程度不同的缺陷，导致1,25-(OH)₂D分泌过多、肠道对钙的吸收增加以及血浆离子钙适度升高。数据的计算机分析不支持将结石患者分为肠道吸收过多者或肾脏排泄减少者的概念。逐步判别分析选择血浆白蛋白、尿pH值、ECa(U)、血浆磷酸盐、GFR和NcAMP作为导致对照者和复发性结石患者差异的最重要变量。通过这个程序，我们对复发性结石患者的正确分类获得了93%的敏感性和96%的特异性。因此，该分析对于预测单发性结石患者复发性结石形成的风险可能有价值。
