University of Central Florida School of Medicine, Orlando, FL, USA.
Division of Nephrology, Nemours Children's Hospital, Nemours Healthcare System, Orlando, FL, USA.
J Pediatr Urol. 2022 Feb;18(1):25.e1-25.e8. doi: 10.1016/j.jpurol.2021.10.010. Epub 2021 Oct 20.
The natural history of asymptomatic nephrolithiasis (AN) in children is not well defined. Furthermore, there is no guidance on the utility of repeated renal ultrasound evaluations in this same population. Follow-up ultrasound studies are often obtained as frequently as every 6 months. The goal of this study is to assess the follow-up ultrasound interval in the management of these patients.
A retrospective IRB approved chart review was performed for patients seen for non-cysteine AN between 2012 and 2019. AN was defined as patients without obstructive uropathy abdominal, flank pain and/or gross hematuria. Asymptomatic stones were discovered incidentally or after an acute stone event. Patients with pre-existing renal anomalies and the timepoints with stone passage or stone procedure were excluded. Descriptive statistics were used for demographic information. Multiple linear regression was used to analyze risk factors. Statistical significance was set to p < 0.05.
Twenty-nine patients had 90 ultrasounds. The average age at diagnosis was 10.8 ± 6.2 years. The average number of ultrasound studies per patient was 3.2 ± 1.7. The median time between follow-up ultrasounds was 5.2 months [IQR 2.8-10.0]. Median follow-up of patients was 10.6 months [IQR 4.9-21.9]. The change in total stone burden occurred at a rate of 0.11 mm/month (CI [-0.06-0.28], p = 0.20, r = 0.42) or 0.66 mm/6 months. Patients with more renal stones had almost a threefold increase in stone burden compared to patients with fewer renal stones (2.98 [CI 1.34-4.62], p=0.001, r=0.33). Patients with a family history of stones had a twofold increase in the size of their largest stone when compared to patients without a family history (1.97 [CI 0.26-3.68], p=0.02, r=0.60.
A complex interplay of multiple factors influence the progression of AN in children. Children with a greater number of stones have a higher increase in total stone burden and children with a family history of stones have a faster increase in largest stone size. These patients may require more frequent imaging studies. The small change in stone size over time favors a longer than 6-month interval for many children.
儿童无症状肾结石（AN）的自然病史尚不清楚。此外，对于同一人群中重复进行肾脏超声检查的效用尚无指导意见。通常会以每 6 个月的频率进行随访超声检查。本研究的目的是评估这些患者的管理中随访超声检查的间隔。
对 2012 年至 2019 年间就诊的非胱氨酸 AN 患者进行了回顾性 IRB 批准的图表审查。无症状肾结石定义为无梗阻性尿路疾病、腹痛、腰痛和/或肉眼血尿的患者。无症状结石是偶然发现的，或者是在急性结石事件后发现的。排除了有预先存在的肾脏异常的患者以及有结石通过或结石手术的时间点。对人口统计学信息进行描述性统计。采用多元线性回归分析危险因素。统计学意义设定为 p < 0.05。
29 例患者共进行了 90 次超声检查。诊断时的平均年龄为 10.8 ± 6.2 岁。每位患者的平均超声检查次数为 3.2 ± 1.7。随访超声检查的中位数时间为 5.2 个月[IQR 2.8-10.0]。患者的中位随访时间为 10.6 个月[IQR 4.9-21.9]。总的结石负担变化率为 0.11mm/月（CI [-0.06-0.28]，p=0.20，r=0.42）或 0.66mm/6 个月。肾结石数量较多的患者的结石负担几乎是肾结石数量较少的患者的三倍（2.98[CI 1.34-4.62]，p=0.001，r=0.33）。有结石家族史的患者的最大结石尺寸增加了两倍，而没有结石家族史的患者则增加了两倍（1.97[CI 0.26-3.68]，p=0.02，r=0.60）。
多种因素的复杂相互作用影响儿童无症状肾结石的进展。结石数量较多的患者，总结石负担增加得更高，有结石家族史的患者，最大结石尺寸增加得更快。这些患者可能需要更频繁的影像学检查。随着时间的推移，结石大小的微小变化有利于许多儿童的随访间隔超过 6 个月。
