Strohmaier W L, Schlee-Giehl K, Bichler K H
Department of Urology, Eberhard-Karls-University, Tübingen, Germany.
Eur Urol. 1996;30(1):103-7. doi: 10.1159/000474153.
The treatment of hypercalciuria is controversial. This study investigated whether the osteocalcin response (OCR) to a calcium-restricted diet is a potential tool for the differential therapy of hypercalciuria. 56 patients with calcium urolithiasis were investigated.
Osteocalcin (OC) was measured on a free diet (OC 1) and after a calcium-restricted diet (400 mg/24 h for 1 week, OC 2). The OCR was expressed as 100 x (OC 2 - OC 1)/OC 1. A calcium load test and vertebral mineral density measurements (L2-L4) were performed additionally.
27 patients showed diet-dependent hypercalciuria, 15 of them being classified as absorptive hypercalciuria type II (AH II). 12 were normocalciuric (NC). 29 patients had diet-independent hypercalciuria, 22 being classified as renal hypercalciuria (RH), 7 as absorptive hypercalciuria type I (AH I). 22 patients (42%) showed a positive OCR, indicating an increased bone turnover. Vertebral mineral density was lower in patients with positive than with negative OCR. Generally patients with RH or NC showed a positive OCR, patients with AH a negative or no OCR. 2 patients with AH, however, showed highly positive OCR, indicating negative calcium balance. Long-term follow-up on a low calcium diet showed a steady decrease in bone mineral density.
This demonstrates that the OCR is more reliable to determine the appropriate management of hypercalciuria than calcium load tests. For practical purposes, we suggest treating hypercalciuric patients with positive OCR with thiazides; diet-dependent hypercalciuria with negative OCR should be treated with a low calcium diet.
高钙尿症的治疗存在争议。本研究调查了骨钙素对钙限制饮食的反应（OCR）是否是高钙尿症差异化治疗的潜在工具。对56例钙结石患者进行了研究。
在自由饮食状态下（OC 1）以及钙限制饮食后（400mg/24小时，持续1周，OC 2）测量骨钙素（OC）。OCR表示为100×（OC 2 - OC 1）/OC 1。另外还进行了钙负荷试验和腰椎骨密度测量（L2-L4）。
27例患者表现为饮食依赖性高钙尿症，其中15例被归类为II型吸收性高钙尿症（AH II）。12例为正常钙尿症（NC）。29例患者表现为饮食非依赖性高钙尿症，22例被归类为肾性高钙尿症（RH），7例为I型吸收性高钙尿症（AH I）。22例患者（42%）表现出阳性OCR，表明骨转换增加。OCR阳性的患者腰椎骨密度低于阴性患者。一般来说，RH或NC患者表现出阳性OCR，AH患者表现出阴性或无OCR。然而，2例AH患者表现出高度阳性OCR，表明钙负平衡。低钙饮食的长期随访显示骨密度持续下降。
这表明OCR在确定高钙尿症的适当治疗方法方面比钙负荷试验更可靠。出于实际目的，我们建议对OCR阳性的高钙尿症患者使用噻嗪类药物治疗；OCR阴性的饮食依赖性高钙尿症患者应采用低钙饮食治疗。
