Histology of upper pole is unaffected by prenatal diagnosis in duplex system ureteroceles

We determined whether the histology of upper pole nephrectomy specimens vary with prenatal detection or ureterocele position.

Between 1992 and 2000, 95 patients with ureteroceles associated with a duplex system underwent surgical interventions, including upper pole nephrectomy in 60. A total of 55 specimens, of which 25 and 30 involved a prenatal and postnatal diagnosis, and 18 and 37 involved an intravesical and extravesical location, respectively, were available for independent review by a single pathologist. Histological lesions were classified into the 5 categories of chronic interstitial inflammation, fibrosis, tubular atrophy, glomerulosclerosis and dysplasia. Each category was divided into moderate/severe histological lesions (greater than 25% involvement) and minimal/mild lesions (25% or less involvement).

A moderate/severe histological lesion was identified in 38 patients (69%) and a minimal/mild lesion was detected in 17 (31%), while dysplasia was present in 35 (64%). There was no significant difference in histological lesions and mode of presentation. In contrast to intravesical ureteroceles, extravesical ureteroceles were associated with severe fibrosis and tubular atrophy (p <0.05). Chronic interstitial inflammation, fibrosis, tubular atrophy and glomerulosclerosis in each specimen were graded moderate/severe (greater than 25% involved) in 55%, 67%, 66% and 53%, respectively.

Prenatally diagnosed ureteroceles were not associated with less severe upper pole histological lesions. We noted pathological differences when comparing specimens according to ureterocele position, but chronic inflammation and dysplasia were similar in intravesical and extravesical ureterocele cases. It appears that the histological lesions observed are not progressive or reversible. Therefore, the goals of clinical management should focus on providing adequate drainage, antibiotic prophylaxis coverage and followup of reflux rather than the preservation or enhancement of upper pole function.