Cooper Christopher S, Orzel Joanna, Bonnett Megan A, Malicoat Johnny R, Hlas Arman C, Lockwood Gina M, Bridget Zimmerman M
Department of Urology, University of Iowa Hospitals and Clinics, Iowa City, IA, 52242-1089, USA.
Department of Urology, University of Iowa Hospitals and Clinics, Iowa City, IA, 52242-1089, USA.
J Pediatr Urol. 2025 Apr 15. doi: 10.1016/j.jpurol.2025.04.013.
Vesicoureteral reflux (VUR) grade is a factor in assessing risk of clinical outcomes but has poor interobserver reliability. More objective and reliable voiding cystourethrogram (VCUG) parameters including the distal ureteral diameter ratio (UDR) and bladder volume at onset of VUR (Vol) may augment or replace grading systems. We hypothesize that addition of these parameters would provide more reliable prediction of breakthrough UTIs within 1 year of VCUG.
A retrospective review identified 98 children that had VCUG parameters of both UDR and Vol recorded with follow-up of at least 1 year for inclusion in the study. These patients were then assessed for the primary outcome of occurrence of breakthrough UTIs (BUTI) within 1 year of VCUG. Logistic regression and linear mixed model were used to assess the association of patient clinical characteristics and VCUG parameters with the occurrence of BUTI. Predictive ability of the VCUG parameters was assessed by computing the area under the receiver operating characteristic (ROC) curve (AUC) which were compared to identify which is more predictive of BUTI.
Ninety-eight children had 128 VCUGs with 15 occurrences of BUTI within 1 year of a VCUG. Assessments of the association of patient clinical variables and VCUG parameters with BUTI showed a significant association of increased UDR and high VUR grade with greater risk of BUTI. For UDR, the estimated probability of BUTI at the UDR third quartile was 15.0 % compared to 6.2 % at the UDR first quartile, with BUTI odds ratio of 2.68 (95 % CI: 1.39, 5.19) (p = 0.000). For VUR grade, the estimated probability of BUTI was 31.1 % for grade 4-5 compared to 7.0 % for grade 1-2, with BUTI odds ratio of 5.99 (95 % CI: 1.54, 23.26) (p = 0.019). There was no significant association of BUTI with Vol (as % of PBC), and patients' demographics and clinical history. Comparison of the predictive ability of the three VCUG parameters as predictor of BUTI within 1 year of VCUG using area of the ROC curve showed that UDR was the most predictive with AUC of 0.687 (95 % CI: 0.562, 0.812). AUC was lower for VUR grade, 0.466 (95 % CI: 0.256, 0.675), and Vol, 0.339 (95 % CI: 0.206, 0.472).
A more reliable classification system for VUR, with improved predictive accuracy regarding BUTI, may be developed incorporating UDR. Whether VUR grade can be completely replaced by UDR measurements requires further evaluation with larger number of patients.
膀胱输尿管反流（VUR）分级是评估临床结局风险的一个因素，但观察者间可靠性较差。包括远端输尿管直径比（UDR）和VUR发作时膀胱容量（Vol）在内的更客观、可靠的排尿性膀胱尿道造影（VCUG）参数可能会增强或取代分级系统。我们假设增加这些参数将能更可靠地预测VCUG后1年内的突破性尿路感染。
一项回顾性研究确定了98例记录了UDR和Vol这两个VCUG参数且随访至少1年的儿童纳入本研究。然后评估这些患者在VCUG后1年内发生突破性尿路感染（BUTI）的主要结局。采用逻辑回归和线性混合模型评估患者临床特征和VCUG参数与BUTI发生之间的关联。通过计算受试者工作特征（ROC）曲线下面积（AUC）评估VCUG参数的预测能力，并进行比较以确定哪个参数对BUTI的预测性更强。
98例儿童共进行了128次VCUG检查，其中15例在VCUG后1年内发生BUTI。对患者临床变量和VCUG参数与BUTI之间关联的评估显示，UDR增加和VUR分级高与BUTI风险增加显著相关。对于UDR，UDR第三四分位数时BUTI的估计概率为15.0%，而UDR第一四分位数时为6.2%，BUTI优势比为2.68（95%CI：1.39，5.19）（p = 0.000）。对于VUR分级，4 - 5级时BUTI的估计概率为31.1%，而1 - 2级时为7.0%，BUTI优势比为5.99（95%CI：1.54，23.26）（p = 0.019）。BUTI与Vol（占预计膀胱容量的百分比）、患者人口统计学特征和临床病史无显著关联。使用ROC曲线面积比较三个VCUG参数作为VCUG后1年内BUTI预测指标的预测能力，结果显示UDR预测性最强，AUC为0.687（95%CI：0.562，0.812）。VUR分级的AUC较低，为0.466（95%CI：0.256，0.675），Vol的AUC为0.339（95%CI：0.206，0.472）。
结合UDR可能会开发出一种更可靠的VUR分类系统，对BUTI的预测准确性更高。UDR测量是否能完全取代VUR分级需要在更多患者中进一步评估。
