Otto Brandon J, Bozorgmehri Shahab, Kuo Jennifer, Canales Muna, Bird Vincent G, Canales Benjamin
1 Department of Urology, University of Florida College of Medicine , Gainesville, Florida.
2 Division of Nephrology, Hypertension, and Transplantation, Department of Medicine, University of Florida College of Medicine , Gainesville, Florida.
J Endourol. 2017 Dec;31(12):1335-1341. doi: 10.1089/end.2017.0352.
Despite guidelines, routine 24-hour urine testing is completed in <10% of high-risk, recurrent stone formers. Using surrogates for metabolic testing, such as key patient characteristics, could obviate the cost and burden of this test while providing information needed for proper stone prevention counseling.
We performed a retrospective study of 392 consecutive patients from 2007 to 2014 with ≥2 lifetime stone episodes, >70% calcium oxalate by mineral analysis, and ≥1 24-hour urine collection. We compared mean 24-hour urine values by age in decades. We used logistic regression and receiver operating characteristic (ROC) curve analysis to assess the predictive ability of age, gender, body mass index (BMI), and comorbidities to detect abnormal 24-hour urine parameters.
The mean age of the cohort was 51 ± 16 years. Older age was associated with greater urinary oxalate (p-trend <0.001), lower urinary uric acid (UA) (p-trend = 0.007), and lower urinary pH (p-trend <0.001). A nonlinear association was noted between age and urinary calcium or citrate (calcium peaked at 40-49 years, p = 0.03; citrate nadired at 18-29 years, p = 0.001). ROC analysis of age, gender, and BMI to predict 24-hour urine abnormalities performed the best for hyperuricosuria (area under the curve [AUC] 0.816), hyperoxaluria (AUC 0.737), and hypocitraturia (AUC 0.740). Including diabetes mellitus or hypertension did not improve AUC significantly.
In our recurrent calcium oxalate cohort, age significantly impacted urinary calcium, oxalate, citrate, and pH. Along with gender and BMI, age can be used to predict key 24-hour urine stone risk results. These data lay the foundation for a risk prediction tool, which could be a surrogate for 24-hour urine results in recurrent stone formers, who are unwilling or unable to complete metabolic testing. Further validation of these findings is needed in other stone populations.
尽管有相关指南，但在高风险、复发性结石形成者中，完成常规24小时尿液检测的比例不到10%。使用代谢检测的替代指标，如关键患者特征，可避免此项检测的成本和负担，同时提供适当的结石预防咨询所需的信息。
我们对2007年至2014年连续收治的392例患者进行了一项回顾性研究，这些患者终生结石发作≥2次，矿物分析显示草酸钙含量>70%，且至少有1次24小时尿液收集。我们按十年一组比较了不同年龄组的平均24小时尿液值。我们使用逻辑回归和受试者工作特征（ROC）曲线分析来评估年龄、性别、体重指数（BMI）和合并症对检测异常24小时尿液参数的预测能力。
该队列的平均年龄为51±16岁。年龄越大，尿草酸含量越高（p趋势<0.001），尿酸（UA）排泄量越低（p趋势=0.007），尿液pH值越低（p趋势<0.001）。年龄与尿钙或枸橼酸盐之间存在非线性关联（钙在40 - 49岁达到峰值，p = 0.03；枸橼酸盐在18 - 29岁降至最低点，p = 0.001）。对年龄、性别和BMI进行ROC分析以预测24小时尿液异常情况，对高尿酸尿症（曲线下面积[AUC] 0.816）、高草酸尿症（AUC 0.737）和低枸橼酸尿症（AUC 0.740）的预测效果最佳。纳入糖尿病或高血压并未显著提高AUC。
在我们的复发性草酸钙结石队列中，年龄对尿钙、草酸、枸橼酸盐和pH值有显著影响。年龄与性别、BMI一起，可用于预测关键的24小时尿液结石风险结果。这些数据为风险预测工具奠定了基础，该工具可作为不愿或无法完成代谢检测的复发性结石形成者24小时尿液检测结果的替代指标。其他结石人群需要对这些发现进行进一步验证。
