[Repeat operation to correct the ureteropelvic segment in hydronephrosis in children]

The results of surgical correction of 487 ureteropelvic segments (UPS) were studied in 455 patients (age 4 months to 15 years). Good results were obtained in correction of 477 (98.0%) UPS including 12 after reoperation. Postoperative follow-up lasted for 1 to 25 years. Anastomosis obstruction observed in 12 patients had developed within several postoperative months. In 3 patients it appeared 2-14 years after an effective UPS correction. The obstruction resulted from cicatricial transformation of the ureter and aduject fat with or without obliteration of the anastomosis or ureteral transformation into a rigid connective tissue tube unable to carry the functional load. One of the reasons of connective tissue transformation of the ureter may be urine leakage of the anastomosis. An individual reaction to the suture material (catgut) followed by scar process is also possible. Development of destructive changes many years after successful correction of UPS may arise due to inflammatory process ending in sclerosis. Some moments in pathogenesis of scar transformation of the ureter remains unknown and need further studies. Repeated correction of UPS was effective in all 15 patients. This intervention should be performed at least after 5-6 months after the failure of the first operation. To prevent the scar process, the patients must be followed up for many years and therapeutic methods should be perfected.