Histology of the upper pole in complete urinary duplication--does it affect surgical management?

To review the histological change in the upper pole of excised duplex kidneys and assess whether ante-natal diagnosis might predispose to more conservative surgical management of this abnormality.

Fifty consecutive patients undergoing upper pole hemi-nephroureterectomy for ectopic ureter or ectopic ureterocele between 1980 and 1992 had their histology reviewed and assessed for dysplastic, inflammatory and obstructive change.

Segmental scarring and chronic and acute inflammatory change occurred consistently and the degree of inflammation seemed unaffected by antenatal diagnosis. Dysplasia was seen in 70% of patients with ureterocele and in only 30% of those with ectopic ureter. One patient had normal histology.

There was no evidence of reversible histological change in patients with ectopic ureter and ectopic ureterocele who were diagnosed ante-natally. Preservation of the upper pole of the kidney does not seem justified in the light of the histological evidence.