Clinical characteristics of patients with ureteral endometriosis and severe renal impairment identified by diuretic renal dynamic imaging.

PURPOSE: This study aimed to summarize the clinical characteristics, surgical management, and follow-up outcomes of patients with severe renal impairment caused by ureteral endometriosis. METHODS: We conducted a retrospective analysis of the clinical data of 15 patients with severe renal impairment caused by ureteral endometriosis treated at the First Hospital of Peking University between January 2000 and January 2022. RESULTS: Among the 15 patients, 3 (20.0%) were asymptomatic, whereas 12 (80.0%) reported endometriosis-related pain and/or urinary symptoms. Seven patients (46.7%) reported lumbar discomfort. All patients underwent preoperative diuretic renography, which showed an affected-kidney glomerular filtration rate (GFR) of <15 mL/min in all cases. Despite severe impairment of the affected kidney, only one patient had elevated serum creatinine levels, suggesting that serum creatinine may fail to detect severe unilateral renal impairment when contralateral renal function is preserved. Eight patients (53.3%) underwent ipsilateral nephrectomy, four (26.7%) underwent ureteroneocystostomy, and three (20.0%) underwent ureterolysis. During a median follow-up of 61 months, the majority of patients' symptoms improved. Among the seven patients who underwent kidney function-preserving procedures, hydronephrosis disappeared in six patients and significantly improved in one patient on postoperative ultrasonography. No reoperation for recurrent ureteral obstruction was documented during follow-up. CONCLUSION: Delayed diagnosis of ureteral endometriosis may lead to severe unilateral renal impairment and even the need for nephrectomy. Normal serum creatinine levels do not exclude severe dysfunction of the affected kidney. Early urinary tract imaging, split renal function assessment, individualized surgery, and long-term follow-up are essential for renal preservation.