Histology of Upper Pole Kidney in Patients with Ureterocele

Kim, Woo Jin; Kim, Hwal Woong; Hwa, Jeong Seok; Chung, Ky Hyun

Abstract

PURPOSE: The histological changes in the upper pole of excised duplex kidneys with ureterocele were reviewed and the histological variations with respect to age and ureterocele position were assessed.
MATERIALS AND METHODS
During the last ten years, 10 patients with duplex system ureterocele underwent an upper pole nephrectomy. A total of 10 specimens, of which 4 and 6 were diagnosed at younger than 1 year old and older than 1 year old, and 5 each involving intravesical and ectopic locations, respectively, were available for independent review by a single pathologist. Histological lesions were classified into the 5 categories; chronic interstitial inflammation, interstitial 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).
RESULTS
Chronic interstitial inflammation, interstitial fibrosis, tubular atrophy, glomerulosclerosis and dysplasia in each of the specimens were graded as moderate/severe (greater than 25% involved) in 50, 50, 60, 10 and 80% of the subjects, respectively. The ureteroceles detected at an early stage were not associated with less severe upper pole histological lesions. Also, no pathological differences were observed when comparing specimens according to the ureteroceles positions.
CONCLUSIONS
It appears that the histological lesions observed may not be progressive or reversible. Therefore, it is suggested that enhancement of the upper pole renal function seems unjustified in the light of the histological evidence, and the goals of clinical management should focus on preventing complications and secondary procedures.