Can histologic changes of the upper pole justify a conservative approach in neonatal duplex ectopic ureterocele?

The aim of this study was to review the histology of the upper-pole segment in patients with duplex-system ectopic ureterocele (DEU) to determine if less aggressive surgery is justified in prenatally-diagnosed cases. The study included 15 consecutive patients with DEU treated between 1991 and 1999. The diagnosis was made according to the criteria of the Section on Urology of the American Academy of Pediatrics. The histology specimens were assessed for dysplastic, inflammatory, and obstructive changes. All 15 patients were surgically treated by heminephro-ureterectomy and the surgical specimens were histologically examined. Nine cases were diagnosed prenatally; the histology of the upper-pole segment in these patients showed segmental renal microcystic dysplasia, chondroid metaplasic islands, and an inflammatory tubulointerstitial nephropathy in 6 (66.6%) and nephroblastomatosis in 2 (22.2%). The histology of the 6 postnatally-diagnosed patients showed segmental multicystic renal dysplasia, inflammatory tubulo-interstitial nephropathy, and segmental parenchymal scars. The upper-pole histology of the prenatally-diagnosed patients did not show any evidence of reversible histologic changes. Considering this findings and the good outcome of patients treated with upper-pole nephroureterectomy, less aggressive surgery with preservation of the upper pole does not seem justified.