Clinico-pathological correlation in duplex system ectopic ureters and ureteroceles: can preoperative work-up predict renal histology?

PURPOSE: Upper pole histology has been poorly investigated in duplex system ectopic ureters and ureteroceles. We aimed to determine the differences in histology between the conditions, and to identify clinical markers of renal damage. METHODS: Twenty-two patients undergoing partial nephrectomy between 2001 and 2007 for poorly functioning upper poles associated with ectopic ureters (n = 11) or ureteroceles (n = 11) were considered. Histology was classified into three groups: normal, chronic interstitial nephritis (CIN), and dysplasia. Clinical and radiological variables were compared between the two conditions and between cases with normal and abnormal histology. RESULTS: Of the 22 upper pole specimens, 9 had normal histology, 8 dysplasia, and 5 CIN. Statistical analysis failed to show any significant difference in preoperative variables or histology between ectopic ureters and ureteroceles, and in preoperative variables between cases with normal and abnormal histology. CONCLUSIONS: We did not find significant differences in the histology of upper poles associated with ectopic ureters and ureteroceles. Histology was normal in more than one-third of patients, although the poles were poorly functioning. We hypothesize that these poles were hypoplasic rather than dysplasic. We failed to identify predictors of histological damage. Hence, the latter cannot be considered a factor guiding our decision-making.