Is there an association between histopathological changes in the lower ureter and renal functions? Evaluation of patients who underwent ureteroneocystostomy for ureterovesical obstruction or vesicoureteral reflux.

BACKGROUND/AIM We aimed to assess the relationship between the histological changes of the ureterovesical junction (UVJ) and renal functions. Therefore, we evaluated histological changes of the lower ureter and renal scintigraphy findings of patients for whom ureteroneocystostomy was performed because of vesicoureteral reflux (VUR) or ureterovesical junction obstruction (UVO). MATERIALS AND METHODS UVJ specimens were obtained from 18 children. We investigated the changes in neuronal innervation, muscular morphology, extracellular matrix, and apoptosis rate with renal scintigraphy findings. RESULTS Seven UVO and 11 VUR patients were treated. Alpha-actin expression in smooth muscle cells was found to be lower (P < 0.001) while neuronal defect was more prominent in the UVO group (P = 0.002). The renal functions decreased as the smooth muscle structural defect increased in the VUR group (P < 0.05). CONCLUSION Neuronal tissue and muscle tissue were more defective in the UVO group. The decrease in neuronal fibers and muscle cells explains the pathogenesis of the obstructive group, but no difference was observed regarding the accumulation of collagen type 3 and cellular apoptosis between the VUR and UVO groups. In the VUR group, renal functions decreased while the smooth muscle defect at the distal end of the ureter increased.