From the Department of Urology, University of Washington School of Medicine (M.D.S., J.D.H.), the Division of Urology (M.D.S., M.R.B.) and the Seattle Institute for Biomedical and Clinical Research (B.J.L.), Veterans Affairs Puget Sound Health Care System, and the Institute of Translational Health Sciences (B.H.B.) and the Center for Industrial and Medical Ultrasound, Applied Physics Laboratory (M.R.B.), University of Washington - all in Seattle; the Department of Urology, University of Minnesota, Minneapolis (M.S.B.); and the Departments of Radiology and Imaging Sciences (T.A.H.), Urology (K.J.S., J.E.L.), Cell Biology and Physiology (J.C.W.), and Biostatistics and Health Data Science (Z.L.), Indiana University School of Medicine, Indianapolis.
N Engl J Med. 2022 Aug 11;387(6):506-513. doi: 10.1056/NEJMoa2204253.
The benefits of removing small (≤6 mm), asymptomatic kidney stones endoscopically is unknown. Current guidelines leave such decisions to the urologist and the patient. A prospective study involving older, nonendoscopic technology and some retrospective studies favor observation. However, published data indicate that about half of small renal stones left in place at the time that larger stones were removed caused other symptomatic events within 5 years after surgery.
We conducted a multicenter, randomized, controlled trial in which, during the endoscopic removal of ureteral or contralateral kidney stones, remaining small, asymptomatic stones were removed in 38 patients (treatment group) and were not removed in 35 patients (control group). The primary outcome was relapse as measured by future emergency department visits, surgeries, or growth of secondary stones.
After a mean follow-up of 4.2 years, the treatment group had a longer time to relapse than the control group (P<0.001 by log-rank test). The restricted mean (±SE) time to relapse was 75% longer in the treatment group than in the control group (1631.6±72.8 days vs. 934.2±121.8 days). The risk of relapse was 82% lower in the treatment group than the control group (hazard ratio, 0.18; 95% confidence interval, 0.07 to 0.44), with 16% of patients in the treatment group having a relapse as compared with 63% of those in the control group. Treatment added a median of 25.6 minutes (interquartile range, 18.5 to 35.2) to the surgery time. Five patients in the treatment group and four in the control group had emergency department visits within 2 weeks after surgery. Eight patients in the treatment group and 10 in the control group reported passing kidney stones.
The removal of small, asymptomatic kidney stones during surgery to remove ureteral or contralateral kidney stones resulted in a lower incidence of relapse than nonremoval and in a similar number of emergency department visits related to the surgery. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and the Veterans Affairs Puget Sound Health Care System; ClinicalTrials.gov number, NCT02210650.).
目前尚不清楚经内镜切除小（≤6 毫米）、无症状肾结石的益处。现行指南将此类决策留给泌尿科医生和患者。一项涉及较年长患者和非内镜技术的前瞻性研究以及一些回顾性研究支持观察。然而，已发表的数据表明，在较大结石被移除时留在原处的约一半小肾结石在手术后 5 年内引起了其他有症状的事件。
我们进行了一项多中心、随机、对照试验，在经内镜切除输尿管或对侧肾结石时，38 例患者（治疗组）接受了剩余小、无症状结石的切除，而 35 例患者（对照组）未接受切除。主要结局是通过未来急诊科就诊、手术或继发性结石生长来衡量的复发。
在平均随访 4.2 年后，治疗组的复发时间长于对照组（对数秩检验，P<0.001）。治疗组的限制平均（±SE）复发时间比对照组长 75%（1631.6±72.8 天比 934.2±121.8 天）。治疗组的复发风险比对照组低 82%（风险比，0.18；95%置信区间，0.07 至 0.44），治疗组有 16%的患者出现复发，而对照组有 63%的患者出现复发。治疗组的手术时间平均增加 25.6 分钟（四分位间距，18.5 至 35.2）。治疗组 5 例和对照组 4 例患者在手术后 2 周内急诊就诊。治疗组 8 例和对照组 10 例患者报告有肾结石排出。
与未切除相比，在经内镜切除输尿管或对侧肾结石手术时切除小、无症状肾结石可降低复发率，且与手术相关的急诊就诊率相似。（由美国国立糖尿病、消化和肾脏疾病研究所和退伍军人事务部普吉特湾医疗保健系统资助；ClinicalTrials.gov 编号，NCT02210650）。
