Background Plasma cystatin C is a reliable marker to estimate kidney function; however, it is unknown whether this remains true in patients receiving continuous KRT (CKRT). In this study, we tested the hypothesis that lower concentrations of plasma cystatin C during the first 3 days of CKRT would predict kidney function recovery. Methods We performed a retrospective observational study of 72 patients from a 126-patient, single-center CKRT study. We studied two a priori defined cohorts of patients without advanced CKD who had AKI requiring CKRT: (1) with early kidney function recovery defined as liberation from KRT within 7 days of CKRT initiation versus (2) with delayed kidney function recovery defined as receipt of KRT for >21 days or death while on KRT. Subsequent analysis included patients with advanced CKD and intermediate kidney function recovery (liberation between 8 and 21 days). Cystatin C was then measured on stored plasma, urine, and dialysis effluent collected before CKRT initiation and on days 1, 2, and 3 of CKRT. Results Plasma cystatin C was significantly lower in patients with early kidney function recovery in comparison with patients with delayed kidney function recovery on days 1 (1.79 versus 2.39 mg/L), 2 (1.91 versus 2.38 mg/L), and 3 (2.04 versus 2.67 mg/L) of CKRT. Sieving coefficient and CKRT clearance of cystatin C were similar for patients with early and delayed kidney function recovery. The lowest plasma cystatin C concentration on days 1–3 of CKRT predicted early kidney function recovery with an area under the receiver operating curve of 0.77 (P=0.002), positive likelihood ratio of 5.60 for plasma cystatin C <1.30 mg/L, and negative likelihood ratio of 0.17 for plasma cystatin C ≥1.88 mg/L. Conclusions Lower plasma cystatin C concentrations during the first 3 days of CKRT are associated with early kidney function recovery....

中文翻译：

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胱抑素 C 和急性肾损伤需要持续 KRT 的患者的肾功能恢复


背景 血浆胱抑素 C 是估计肾功能的可靠标志物;然而，尚不清楚接受连续 KRT （CKRT） 的患者是否仍然如此。在这项研究中，我们检验了 CKRT 前 3 天血浆胱抑素 C 浓度较低可预测肾功能恢复的假设。方法 我们对来自 126 名患者的单中心 CKRT 研究的 72 名患者进行了回顾性观察研究。我们研究了两个先验定义的无晚期 CKD 且需要 CKRT 的 AKI 患者队列：（1） 肾功能早期恢复定义为在 CKRT 开始后 7 天内从 KRT 中解放 vs （2） 肾功能恢复延迟定义为接受 KRT >21 天或在接受 KRT 期间死亡。随后的分析包括晚期 CKD 和中等肾功能恢复 （8 至 21 天缓解） 的患者。然后在 CKRT 开始前以及 CKRT 的第 1 天、第 2 天和第 3 天测量胱抑素 C。结果 与肾功能恢复延迟患者相比，早期肾功能恢复患者的血浆胱抑素 C 在 CKRT 第 1 天 （1.79 vs 2.39 mg/L） 、第 2 天 （1.91 vs 2.38 mg/L） 和第 3 天 （2.04 vs 2.67 mg/L） 显著降低。对于肾功能恢复早期和延迟的患者，胱抑素 C 的筛分系数和 CKRT 清除率相似。CKRT 第 1-3 天血浆胱抑素 C 浓度最低预测肾功能恢复早期，受试者工作曲线下面积为 0.77 （P=0.002），血浆胱抑素 C 阳性似然比为 5.60C1.30 mg/L，血浆胱抑素 C 阴性似然比为 0.17≥1.88 mg/L。 结论 CKRT 前 3 天血浆胱抑素 C 浓度较低与早期肾功能恢复相关。