Sriboonlue P, Prasongwattana V, Tungsanga K, Sitprija V
Department of Biochemistry, Faculty of Medicine, Khon Kean University, Thailand.
J Med Assoc Thai. 1990 Dec;73(12):684-9.
Urinary supersaturation with respect to calcium oxalate and/or brushite (CaHPO4.2H2O) is critical for the formation of calcium stones. The aim of this study is to use concentration product ratio (CPR) as a tool to assess the state of urine saturation with respect to calcium oxalate and brushite. One 24-h urine specimen from each of 16 healthy city dwellers (GI), 18 healthy villagers (GII) and 28 villagers with renal stones (GIII) was collected and analyzed for calcium, sodium, potassium, phosphate, uric acid, citrate and oxalate. The CPRs of calcium and oxalate and of calcium and phosphate before and after equilibration of the urine with the corresponding seeding crystals were also determined. Urinary volume and the excretion rate of calcium, potassium, uric acid, citrate and oxalate of GII and of sodium, phosphate, uric acid and citrate of GIII were significantly less than those of GI. The CPRs for calcium oxalate and brushite were 2.9 +/- 0.3 and 1.7 +/- 0.2 for GI, 2.7 +/- 0.2 and 1.3 +/- 0.1 for GII and 2.5 +/- 0.2 and 1.1 +/- 0.1 for GIII, respectively. The CPR values indicated that urine of all groups was generally supersaturated with respect to calcium oxalate salt (CPRs were above 1) and were not different among the groups. With regard to brushite, urine was also supersaturated but the state of supersaturation was less than that of calcium oxalate. Furthermore, instead of being supersaturated, brushite in many urine specimens of GIII was undersaturated and its mean CPR was even significantly less than that of GI (P less than 0.01).
草酸钙和/或透钙磷石（CaHPO₄·2H₂O）的尿液过饱和度对于钙结石的形成至关重要。本研究的目的是使用浓度积比（CPR）作为一种工具，来评估尿液相对于草酸钙和透钙磷石的饱和状态。收集了16名健康城市居民（GI组）、18名健康村民（GII组）和28名肾结石村民（GIII组）每人的一份24小时尿液标本，分析其中钙、钠、钾、磷酸盐、尿酸、柠檬酸盐和草酸盐的含量。还测定了尿液与相应晶种平衡前后钙与草酸盐以及钙与磷酸盐的CPR。GII组的尿量以及钙、钾、尿酸、柠檬酸盐和草酸盐的排泄率，GIII组的钠、磷酸盐、尿酸和柠檬酸盐的排泄率均显著低于GI组。GI组草酸钙和透钙磷石的CPR分别为2.9±0.3和1.7±0.2，GII组为2.7±0.2和1.3±0.1，GIII组为2.5±0.2和1.1±0.1。CPR值表明，所有组的尿液相对于草酸钙盐总体上都是过饱和的（CPR大于1），且各组之间无差异。对于透钙磷石，尿液也是过饱和的，但过饱和状态低于草酸钙。此外，GIII组许多尿液标本中的透钙磷石不是过饱和，而是不饱和，其平均CPR甚至显著低于GI组（P小于0.01）。
