Clinical characteristics of ureteral endometriosis in patients with deep infiltrating endometriosis: a retrospective cohort study

Ureteral endometriosis is a rare but potentially severe manifestation of DIE, which may lead to hydroureteronephrosis and irreversible renal impairment. This study aimed to characterize the clinical and surgical features of UE in DIE and to identify factors associated with ureteral involvement and hydroureteronephrosis. This retrospective study was conducted at the Department of Gynecologic Oncology, Renji Hospital, Shanghai Jiao Tong University School of Medicine. A total of 838 patients with histologically confirmed DIE were included in this study between January 2014 and November 2025. Among 838 patients with DIE, 171 (20.4%) were diagnosed with UE. UE was predominantly unilateral ( n = 143, 83.6%), with left-sided involvement in 83 patients (48.5%) and right-sided in 60 patients (35.1%). Multivariate logistic regression analysis identified age (OR = 1.04, 95% CI 1.01–1.07, p = 0.002), history of endometriosis-related surgery (OR = 1.71, 95% CI 1.13–2.57, p = 0.011), low back soreness (OR = 3.86, 95% CI 2.39–6.24, p < 0.001), urinary frequency (OR = 4.27, 95% CI 1.84–9.92, p < 0.001), uterosacral ligament nodules (OR = 1.75, 95% CI 1.19–2.59, p = 0.005) and rectovaginal septum nodules (OR = 3.25, 95% CI 1.15–9.16, p = 0.026) as factors independently associated with UE. A significantly higher proportion of patients in the UE group had a history of endometriosis-related surgery compared with the non-UE group (30.4% vs. 18.6%, p < 0.001). Hydroureteronephrosis was present in 45% of patients with UE. Intrinsic UE accounted for 8.8% of cases and was more frequent among patients with hydroureteronephrosis than among those without (18.2% vs. 1.1%, P < 0.001). Hydroureteronephrosis was also associated with longer operative times and postoperative hospital stays. Among the 40 patients who underwent renal scintigraphy, 22 (55%) patients had moderate-to-severe impairment of differential renal function in the hydroureteronephrotic kidney, and 7 (17.5%) patients had a nonfunctioning kidney. Ureteral endometriosis was frequently observed in this selected surgical DIE cohort and was frequently associated with hydroureteronephrosis and renal impairment. Given that symptoms may remain subtle even in the presence of hydroureteronephrosis, reliance on clinical presentation alone is insufficient for early detection. Therefore, early recognition requires integration of clinical features, imaging, and multidisciplinary management to enable timely diagnosis and prevent irreversible renal damage.