Table 1_Reduced kidney size and renal function of high-grade vesicoureteral reflux and intrarenal reflux in contrast-enhanced voiding urosonography.docx

BackgroundVesicoureteral reflux (VUR) is a common pediatric urological condition associated with renal scarring, hypertension, and chronic kidney disease. Contrast-enhanced voiding urosonography (ceVUS) has emerged as a promising technique for diagnosing and evaluating VUR, with intrarenal reflux (IRR) often detected using this method. This study aimed to explore the relationship between different VUR grades and IRR on ceVUS, and assess the impact of VUR and IRR on kidney size and function.
MethodsWe reviewed all ceVUS studies from January 2019 to December 2023 conducted at West China Hospital, Sichuan University. Both video clips and digital images of the ceVUS examinations were recorded. A total of 220 uretero-renal units (URUs) of 110 children (67 males and 43 females) were included in this study.
ResultsAmong the 220 URUs assessed, 134 were diagnosed with VUR, and 25 exhibited IRR, with IRR exclusively observed in patients with grade II VUR or higher. Upon age and sex matching, the severity of IRR showed a significant positive correlation with high-grade VUR (P < 0.001). Notably, patients with high-grade VUR and IRR displayed reduced kidney size compared to those without VUR or IRR (P < 0.05). Furthermore, patients with high-grade VUR and IRR had reduced DMSA renal function (P = 0.015, P = 0.012, respectively), and patients with high-grade VUR had more DMSA scars (P = 0.027), compared with those without VUR or IRR.
ConclusionOur study highlights that on ceVUS, the IRR degree was associated with the high-grade VUR, along with reductions in kidney size and renal function in patients with high-grade VUR and IRR.

背景 膀胱输尿管反流（Vesicoureteral reflux, VUR）是一类常见的儿科泌尿外科疾病，可伴随肾瘢痕形成、高血压及慢性肾脏病发生。增强排尿式泌尿系超声（Contrast-enhanced voiding urosonography, ceVUS）现已成为诊断与评估VUR的极具应用前景的技术手段，该方法常可检测出肾内反流（Intrarenal reflux, IRR）。本研究旨在探讨ceVUS成像下不同VUR分级与肾内反流之间的关联，并评估VUR及肾内反流对肾脏体积与肾功能的影响。
方法 回顾性分析2019年1月至2023年12月于四川大学华西医院完成的所有ceVUS检查资料。本研究记录了ceVUS检查的视频片段与数字化图像。最终纳入110名儿童（其中男性67例，女性43例）的220个输尿管肾单位（Uretero-renal units, URU）进行分析。
结果 在纳入评估的220个输尿管肾单位中，134个被确诊为VUR，25个检出肾内反流，且肾内反流仅见于VUR分级Ⅱ级及以上的患者。经年龄与性别匹配后，肾内反流的严重程度与高分级VUR呈显著正相关（P < 0.001）。值得注意的是，合并高分级VUR与肾内反流的患者，其肾脏体积较无VUR及肾内反流的患者显著减小（P < 0.05）。进一步分析显示，合并高分级VUR与肾内反流的患者，其二巯基丁二酸（Dimercaptosuccinic acid, DMSA）检测的肾功能指标均有所降低（分别对应P=0.015、P=0.012）；与无VUR及肾内反流的患者相比，高分级VUR患者的DMSA检测可见肾瘢痕灶更多（P=0.027）。
结论 本研究表明，在ceVUS成像中，肾内反流的严重程度与高分级VUR存在关联，且合并高分级VUR与肾内反流的患者会出现肾脏体积减小与肾功能下降。