Necessity of performing voiding cystourethrography for children with unilateral multicystic dysplastic kidney
The purpose of this study was to resolve the clinical question as to whether all patients with unilateral multicystic dysplastic kidney (MCDK) should receive voiding cystourethrography (VCUG).
This is a retrospective study using cross-sectional analysis. Seventy-five children with unilateral MCDK were enrolled, excluding patients with other genetic or chromosome abnormalities, spinal cord diseases, or anal atresia. We reviewed their records from medical charts and calculated risk factors for abnormal VCUG using multivariate logistic regression analysis.
Abnormal VCUG findings were present in 24 of 75 patients (32.0%), specifically, vesicoureteral reflux (VUR) in 8 (10.6%), including high-grade VUR in 2 (2.7%), and only lower urinary tract or bladder disease in 16 (21.3%). In multivariate analysis, only abnormal findings by ultrasonography was an independent risk factor for abnormal VCUG findings with statistical significance in multivariate analysis (OR 6.57; 95% CI 1.99–26.26; P = 0.002). When we excluded five patients who showed similar findings by ultrasonography and VCUG, abnormal findings by ultrasonography were again calculated as an independent risk factor (OR 4.44; 95% CI 1.26–28.42; P = 0.02). Sensitivity, specificity, positive predictive value, and negative predictive value of abnormal findings by ultrasonography to predict urologic anomalies by VCUG in these children were 83%, 59%, 49%, and 88%, respectively. Two children required a third ultrasonography to detect abnormal findings.
We can select, using only abnormal findings by ultrasonography, children with unilateral MCDK who should undergo VCUG. We would also like to emphasize that ultrasonography should be performed repeatedly to detect congenital anomalies of the urinary tract.
KeywordsMulticystic dysplastic kidney (MCDK) Voiding cystourethrography (VCUG) Vesicoureteral reflux (VUR) Congenital anomalies of the kidney and urinary tract (CAKUT) Ultrasonography Children
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
The design and execution of this study were in accordance with the ethical standards of the Declaration of Helsinki. The protocol was approved by the Ethics Committee of the National Center for Child Health and Development (No. 1372).
For this type of study, formal informed consent is not required.
- 6.The International Reflux Study Committee (1981) Medical versus surgical treatment of primary vesicoureteral reflux. Pediatr 67:392–400Google Scholar
- 7.Uemura O, Honda M, Matsuyama T, Ishikura K, Hataya H, Yata N, Nagai T, Ikezumi Y, Fujita N, Ito S, Iijima K, Kitagawa T (2011) Age, gender, and body length effects on reference serum creatinine levels determined by an enzymatic method in Japanese children: a multicenter study. Clin Exp Nephrol 15:694–699CrossRefGoogle Scholar