LOWER URINARY-TRACT ABNORMALITIES IN CHILDREN WITH MULTICYSTIC DYSPLASTIC KIDNEY

PURPOSE: To determine the nature and frequency of associated structura l abnormalities of the lower urinary tract in children with multicysti c dysplastic kidney. MATERIALS AND METHODS: The authors reviewed imagi ng findings from studies in 59 children with unilateral multicystic dy splastic kidney. All patients had undergone renal ultrasonography (US) , renal scintigraphy, and voiding cystourethrography. The diagnosis wa s based on characteristic imaging findings (echogenic, cystic kidney a t US that did not function at scintigraphy). RESULTS: Nineteen (32%) p atients had one or more abnormalities of the lower urinary tract. Vesi coureteral reflux was most common (15 patients). Reflux occurred into the contralateral ureter in 12 patients and the ipsilateral atretic ur eter in five (two had bilateral reflux). Four patients had ectopic ure ters: Three cases were ipsilateral and inserted into the prostatic ure thra (two cases, both with reflux) or into the seminal vesicle (one ca se); one case was contralateral and inserted into the bladder neck. Fo ur patients had an ipsilateral obstructed single-system ureterocele. F our patients had bladder diverticula. Other abnormalities included hyp ospadias, opacification of a small utricle (not in the patient with hy pospadias), ejaculatory duct reflux, internal urachal sinus, and lipom eningocele with a neurogenic bladder. CONCLUSION: Abnormalities of the lower urinary tract are common in children with unilateral multicysti c dysplastic kidney. Voiding cystourethrography should be performed ro utinely in this population.