Intrinsic unilateral ureteral endometriosis: A rare case report

Saad Alenezi: Writing the manuscript, review of literature, revising, submitting the manuscript. Mohammad Zaheer: patient management planning, review of literature & revising the manuscript. Salah Khudair: review of literature, revising the manuscript.

This work did not receive any grant from funding agencies in the public, commercial, or not-for-profit stories.

Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of written consent is available for review by the Editor-in-Chief of this journal in request.

Ethical approval is exempt at our institution.

Not applicable.

Saad Alenezi.

Ureteral endometriosis is a rare but serious cause of renal dysfunction due to its atypical signs and symptoms and late presentation. Multidisciplinary approach early diagnosis is a key for favorable outcomes.

Endometriosis etiology is not clear. However, several mechanisms explain etiology. The most accepted mechanism is the retrograde flow of endometrial cells followed by implantation [17] . This disease affects approximately 10 % to 15 % of women of reproductive age [1] . Three types of endometrioses are described according to the morphology and localization: ovarian, superficial peritoneal and deep infiltrative endometriosis (DIE) [3] . DIE most commonly invades the rectovaginal space, uterosacral ligaments, bowel or urinary tract [5] . Our case was very rare which is non infiltrating but completely isolated intraluminal right lower third endometriosis with long - standing right sided hydronephrosis due to delay in diagnosis and subsequent reduction in renal function. There are two major pathological types of ureteral endometriosis according to the depth of infiltration of the ureteral wall, which are intrinsic and extrinsic. The extrinsic form occurs four times more often than intrinsic [14] . Extrinsic type is caused by invasion of adventitia of the ureter or surrounding connective tissue by endometrial tissue while the intrinsic type of ureteral endometriosis can be defined as involvement of muscularis propria, lamina propria or ureteral lumen with endometrial tissues [10] . Our patient had an intrinsic right ureteral endometriosis, which was confirmed by both endoscopy and the pathologic result with near total obstruction of the lumen. Symptoms of urinary tract endometriosis are not always straightforward. Our patient was asymptomatic except for the occasional dull right iliac fossa pain. She did not complain of the classical symptoms of endometriosis like dysmenorrhea, dyspareunia. Also, she did not complain of any urinary tract symptoms related to menstrual cycle. Gynecological examination and TV/US were done and were unremarkable. The main goal of the treatment should be preservation of renal function, relief of obstruction and prevention of recurrence [12] . Hormonal therapy does not change obstruction secondary to fibrous tissue and adhesions in UE [13] . We did not prefer a hormonal therapy in our patient due to the ureteral obstruction and moderate hydroureteronephrosis. Isolated endometriosis of the ureter as in our case, may be asymptomatic for a long time and eventually lead to renal failure [9] . Surgical modalities of UE may be different according to the type, wither it is intrinsic or extrinsic UE. Elective ureterolysis by laparoscopic or open approach should be indicated in patients with extrinsic lesion <3 cm [15] . Ureterolysis is contraindicated in patients with intrinsic UE due to high recurrence rate and ureteral stenosis [11] . Treatment of patients having intrinsic UE includes resection of the affected ureteric segment and ureteroneocystostomy or endoscopic complete excision of uretic mass with DJS placement as in our case [16] .

Endometriosis is defined as the ectopic growth of endometrial tissue outside the uterine cavity. It is a benign estrogen - dependent gynecological disease that affects 10 to 15 % of women of reproductive age [1] . Symptoms include dysmenorrhea, dyspareunia and chronic pelvic pain (CPP) [2] . Infertility is a common presentation as well. Endometriosis is classified into three types which are superficial, deep infiltrating [DIE] and Endometriomas [3] . DIE is the most severe form of endometriosis, with an estimated prevalence of 1 % in women of reproductive age and 14–20 % in patients with endometriosis and it is defined as penetration >5 mm under the peritoneal surface and can involve organs such as bowel or urinary tract [4] , [5] . Bladder involvement is the most common site for DIE with 70–85 % of cases and ureter involvement with 9–23 % [6] . Hormonal therapy is the first line treatment of DIE [7] . Surgical treatment is indicated in obstruction and hydronephrosis [8] . Endometriosis of the ureter may be asymptomatic for a long time and eventually lead to renal failure [9] . Here we present a case of 44 years old lady present to Emergency department, Al - Jahra hospital, which is a community hospital located in Al - Jahra city. This work has been reported in line with the SCARE 2020 criteria [18] .

A 44-year-old lady known case of hypertension, diabetes and bronchial asthma and past surgical history of laparoscopic sleeve gastrectomy who presented to the emergency department at al Jahra hospital in Kuwait with abdominal pain of 12 h duration. The pain was in right iliac fossa started gradually, dull in nature not radiating to any place and it was associated with nausea and vomiting and dysuria. She is on regular menses. Examination was unremarkable. Family history was insignificant. The laboratory tests were normal. Pelvic abdominal ultrasound was done and showed right mild hydronephrosis. CT scan abdomen with contrast showed right renal distal ureter soft tissue density caused filling defect with mild to moderate hydronephrosis ( Fig. 1 a, b) no renal or ureteric stones detected. Diagnostic ureteroscopy was done and showed normal urethra, urinary bladder and bilateral ureteric orifices. Right ureteroscopy done and showed a pedunculated completely intraluminal rounded ureteric mass lesion at the lower third right ureter ( Fig. 2 a, b). We excised the mass by laser and DJ stent (tumor stent) inserted. Post-operative period was uneventful and the patient was discharged next day. Histopathology revealed normal endometrium tissue and no ureteric tissue was identified ( Fig. 3 a, b). Ureteroscopy was done 1 year after the mass excision and it showed no recurrence of the mass and no ureteral stricture. Follow up CTs were done after 5, 12 months and after 2 years and showed no recurrence of the mass and complete resolution of previous hydronephrosis ( Fig. 4 ) except reduction in differential renal function due to long standing asymptomatic obstruction which was confirmed by MAG3 renal scan. Gynecology team were consulted after the histopathology regarding endometriosis and since it was a pure ureteral endometriosis and since the TV/US was free and the patient didn't have the classical symptoms of endometriosis, the case was entirely for urology team care and nothing by gynecology side to be done. Fig. 1 a: Computed constructed image showing filling defect and right hydronephrosis. b: Axial CT urography showing right hydronephrosis. Fig. 1 Fig. 2 a: Intra op findings: ureteroscopy showing a rounded mass attached to the ureter wall. b: Intra op findings: ureteroscopy showing a rounded mass attached to the ureter wall. Fig. 2 Fig. 3 a: Histopathology showing pure endometrial tissue. b: Histopathology showing pure endometrial tissue. Fig. 3 Fig. 4 Post op CT abdomen after 2 years showing resolution of the previous hydronephrosis. Fig. 4 a: Computed constructed image showing filling defect and right hydronephrosis. b: Axial CT urography showing right hydronephrosis. a: Intra op findings: ureteroscopy showing a rounded mass attached to the ureter wall. b: Intra op findings: ureteroscopy showing a rounded mass attached to the ureter wall. a: Histopathology showing pure endometrial tissue. b: Histopathology showing pure endometrial tissue. Post op CT abdomen after 2 years showing resolution of the previous hydronephrosis.

There is no conflict of interest including any financial or personal relationships with other people or organisations or any work influencers.