Tiselius H G
Department of Urology, University Hospital, Linköping, Sweden.
J Urol. 1992 Sep;148(3 Pt 2):990-4. doi: 10.1016/s0022-5347(17)36797-6.
The relationship between the degree of urine dilution and the risk of calcium oxalate crystallization was studied in 32 urine samples collected from stone formers and normal subjects during an 8-hour period between 10 p.m. and 6 a.m., and in 4-hour urine samples collected during 24-hour periods from 6 patients with calcium stone disease. The risk of calcium oxalate crystallization was analyzed in terms of the increase in oxalate concentration required for a standardized precipitation of crystals of calcium oxalate. The degree of urine dilution was determined with a new instrument (urimho) designed for measuring the concentration, in terms of specific electrical conductivity, in urine samples of droplet size. With this device urine concentration can be expressed in urimho values between 1 and 5. There was a good correlation between recordings of specific electrical conductivity performed with the new device and with a conventional conductivity meter. There was a statistically significant positive correlation between urimho values and calcium oxalate crystallization. Calcium oxalate crystallization greater than 1.3 was not observed in any sample with a urimho value of 2 but it was noted in 31% of the samples with urimho values greater than 2. A positive relationship was also recorded between the urine pH and the urimho level, which is noteworthy because there was an inverse relationship between urine pH and calcium oxalate crystallization. A pH greater than 6 was observed in 78% of the samples with a urimho value of 2 but it was noted in only 27% of the samples with urimho readings between 3 and 5. A considerable variation in the response in urinary flow to ingested volumes was recorded. Therefore, monitoring of urine dilution by means of a sample device like the urimho might be of great help for patients with calcium stone disease in an effort to prevent recurrent stone formation by urine dilution, provided a urimho value of less than 3 can be maintained.
在晚上10点至早上6点的8小时期间，从结石形成者和正常受试者收集的32份尿液样本中，以及从6例草酸钙结石病患者24小时期间收集的4小时尿液样本中，研究了尿液稀释程度与草酸钙结晶风险之间的关系。根据草酸钙晶体标准化沉淀所需的草酸盐浓度增加情况，分析草酸钙结晶的风险。使用一种新仪器（尿密度计）测定尿液稀释程度，该仪器专为测量小滴尺寸尿液样本中基于比电导率的浓度而设计。使用该设备，尿液浓度可以用介于1和5之间的尿密度计值表示。新设备与传统电导率仪进行的比电导率记录之间具有良好的相关性。尿密度计值与草酸钙结晶之间存在统计学上显著的正相关。尿密度计值为2的任何样本中均未观察到草酸钙结晶大于1.3的情况，但在尿密度计值大于2的样本中有31%观察到了这种情况。尿液pH值与尿密度计水平之间也记录到正相关关系，这值得注意，因为尿液pH值与草酸钙结晶之间存在负相关关系。尿密度计值为2的样本中有78%观察到pH值大于6，但在尿密度计读数介于3和5之间的样本中仅27%观察到这种情况。记录到摄入液体量后尿流量反应存在相当大的差异。因此，对于草酸钙结石病患者，通过像尿密度计这样的样本设备监测尿液稀释情况，可能有助于通过尿液稀释预防结石复发，前提是能维持尿密度计值小于3。
