Department of Nephrology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
Key Laboratory of Nephrology (Sun Yat-sen University), Guangdong Provincial Key Laboratory of Nephrology, Guangzhou, China.
Perit Dial Int. 2020 Jan;40(1):84-92. doi: 10.1177/0896860819878658.
International Society for Peritoneal Dialysis guidelines recommend to routinely monitor the total measured clearance (mCl) of small solutes such as creatinine; however, collection of 24-h urine and peritoneal dialysis (PD) fluid is burdensome to patients and prone to errors. We hypothesized that equations could be developed to estimate mCl (estimated clearance (eCl)) using endogenous filtration markers.
In the Guangzhou PD Study ( = 980), we developed eCl equations using linear regression in two-third and validated them in the remaining one-third. Reference tests were mCl for urea nitrogen (UN) (mCl, ml/min) and average mCl for UN and creatinine (mCl, ml/min/1.73 m). Index tests were various eCl equations using UN, creatinine, low-molecular-weight proteins (LMWPs) (beta-trace protein (BTP), beta-2 microglobulin (B2M), and cystatin C), demographic variables, and body size. After reexpression of the equations in the combined data set, we analyzed accuracy (eCl within ± 2.0 units of mCl) and the predictive value of eCl to detect a weekly total standard Kt/V (weekly mCl indexed for total body water) > 1.7 using receiver operating characteristic curve.
Mean age of the cohort was 50 ± 15 years, 53% were male; mCl was 6.9 ± 1.8 and mCl was 7.5 ± 2.8. Creatinine but not UN contributed to eCl for both mCl. LMWP did not improve accuracy for mCl (range 88-89%). BTP and B2M improved the accuracy for mCl (82% vs. 80%); however, differences were small. The area under the curve for predicting a weekly Kt/V > 1.7 was similar for all equations (range 0.79-0.80).
Total small solute clearance can be estimated moderately well in continuous ambulatory PD patients using serum creatinine and demographic variables without urine and dialysate collection.
国际腹膜透析学会指南建议常规监测小分子溶质（如肌酐）的总测量清除率（mCl）；然而，收集 24 小时尿液和腹膜透析（PD）液对患者来说是负担，并且容易出错。我们假设可以开发使用内源性滤过标志物来估计 mCl（估计清除率（eCl））的方程。
在广州 PD 研究（ = 980）中，我们使用三分之二的线性回归开发了 eCl 方程，并在剩余的三分之一中进行了验证。参考测试是用于尿素氮（UN）的 mCl（mCl，ml/min）和用于 UN 和肌酐的平均 mCl（mCl，ml/min/1.73 m）。指标测试是使用 UN、肌酐、低分子量蛋白（LMWP）（β-痕迹蛋白（BTP）、β-2 微球蛋白（B2M）和胱抑素 C）、人口统计学变量和体型的各种 eCl 方程。在组合数据集重新表达方程后，我们分析了准确性（eCl 在 mCl 的±2.0 单位内）和 eCl 预测检测每周总标准 Kt/V（每周 mCl 索引为总体水）>1.7 的价值使用接收者操作特征曲线。
队列的平均年龄为 50±15 岁，53%为男性；mCl 为 6.9±1.8，mCl 为 7.5±2.8。肌酐而非 UN 为两者的 eCl 做出了贡献。LMWP 并未提高 mCl 的准确性（范围 88-89%）。BTP 和 B2M 提高了 mCl 的准确性（82%对 80%）；然而，差异很小。所有方程预测每周 Kt/V>1.7 的曲线下面积相似（范围 0.79-0.80）。
在连续非卧床 PD 患者中，使用血清肌酐和人口统计学变量可以很好地估计总小分子清除率，而无需收集尿液和透析液。
