Department of Urology, Icahn School of Medicine at Mount Sinai, 424 W. 59th Street, Suite 4F, New York, NY, 10019, USA.
Department of Urology and Kidney Transplant, University of Foggia, Foggia, Italy.
World J Urol. 2024 Mar 13;42(1):138. doi: 10.1007/s00345-024-04829-1.
We seek to compare clinical and 24-h urine parameters between pure-uric acid (UA) and UA-CaOx stone formers in our practice and explore how any differences in metabolic profiles could suggest different prevention strategies between the two groups.
We retrospectively reviewed patients with either pure- or mixed-UA nephrolithiasis from 2020 to 2023 at a tertiary care center. We included patients with a 24-h urine collection and a stone analysis detecting any amount of UA. Patients were organized into two cohorts: (1) those with 100% UA stones and (2) < 100% UA stones. Differences in demographic characteristics were compared between pure-UA and UA-CaOx stone formers. Twenty-four hour urine metabolic parameters as well as metabolic abnormalities were compared between the pure-uric acid and mixed-uric acid groups.
We identified 33 pure-UA patients and 33 mixed-UA patients. Patient demographics were similar between the groups (Table 1). Pure- and mixed-UA patients had a similar incidence of metabolic syndrome, diabetes, history of stones, and stone burden. Table 1 Demographic and baseline characteristics among pure- and mixed-uric acid stone formers Pure-uric acid stones (n = 33) Mixed-uric acid stones (n = 33) p-value Median age [IQR] 63.00 [58.00-72.50] 63.00 [53.50-68.00] 0.339 Median BMI [IQR] 28.79 [25.81-33.07] 27.96 [25.81-29.55] 0.534 Gender, n (%) 1.000 Male 21 (63.6) 21 (63.6) Female 12 (36.4) 12 (36.4) Metabolic syndrome, n (%) 17 (51.5) 16 (48.5) 0.806 Diabetes, n (%) 13 (39.4) 12 (36.4) 0.800 History of stones, n (%) 23 (69.7) 22 (66.7) 0.792 Median total stone burden, mm [IQR] 12.00 [6.00-26.50] 13.00 [7.05-20.00] 0.995 Median serum uric acid, mg/dL [IQR] 6.20 [4.80-7.15] 5.90 [4.98-6.89] 0.582 IQR Interquartile range BMI Body Mass Index n number We found the pure-UA cohort to have 24-h lower urine volume (1.53 vs. 1.96 L/day, p = 0.045) and citrate levels (286 vs. 457 mg/day, p = 0.036). UA-CaOx stone formers had higher urinary calcium levels (144 vs. 68 mg/day, p = 0.003), higher urinary oxalate levels (38 vs. 30 mg/day, p = 0.017), and higher median urinary calcium oxalate super-saturation (3.97 vs. 3.06, p = 0.047).
Pure-UA kidney stone formers have different urinary metabolic parameters when compared with UA-CaOx stone formers, thus requiring different and tailored medical management.
我们旨在比较本中心纯尿酸（UA）和 UA-CaOx 结石形成者的临床和 24 小时尿液参数，并探讨代谢特征的任何差异如何提示两组之间不同的预防策略。
我们回顾性分析了 2020 年至 2023 年在一家三级护理中心的纯或混合 UA 肾结石患者。我们纳入了进行 24 小时尿液收集和结石分析的患者，检测到任何量的 UA。患者分为两组：（1）100%UA 结石；（2）<100%UA 结石。比较纯 UA 和 UA-CaOx 结石形成者之间的人口统计学特征差异。比较纯尿酸和混合尿酸组的 24 小时尿液代谢参数和代谢异常。
我们确定了 33 名纯 UA 患者和 33 名混合 UA 患者。两组患者的人口统计学特征相似（表 1）。纯和混合 UA 患者的代谢综合征、糖尿病、结石史和结石负担发生率相似。表 1 纯尿酸和混合尿酸结石形成者的人口统计学和基线特征 纯尿酸结石（n=33） 混合尿酸结石（n=33） p 值 中位数年龄[IQR] 63.00[58.00-72.50] 63.00[53.50-68.00] 0.339 中位数 BMI[IQR] 28.79[25.81-33.07] 27.96[25.81-29.55] 0.534 性别，n（%） 1.000 男性 21（63.6） 21（63.6） 女性 12（36.4） 12（36.4） 代谢综合征，n（%） 17（51.5） 16（48.5） 0.806 糖尿病，n（%） 13（39.4） 12（36.4） 0.800 结石史，n（%） 23（69.7） 22（66.7） 0.792 中位数总结石负担，mm[IQR] 12.00[6.00-26.50] 13.00[7.05-20.00] 0.995 中位数血清尿酸，mg/dL[IQR] 6.20[4.80-7.15] 5.90[4.98-6.89] 0.582 IQR 四分位距 BMI 体重指数 n 数量 我们发现纯 UA 组的 24 小时尿量较低（1.53 比 1.96 L/天，p=0.045），枸橼酸盐水平较低（286 比 457 mg/天，p=0.036）。UA-CaOx 结石形成者的尿钙水平较高（144 比 68 mg/天，p=0.003），尿草酸盐水平较高（38 比 30 mg/天，p=0.017），尿钙草酸超饱和度较高（3.97 比 3.06，p=0.047）。
与 UA-CaOx 结石形成者相比，纯 UA 肾结石形成者的尿液代谢参数不同，因此需要不同的、量身定制的医疗管理。
