Presence of endometrial glands and stroma at extrauterine sites.
Typically occur in the pelvis but can be elsewhere.
Can affect urinary tract most often at bladder and ureter.
Pathogenesis
Theories include retrograde menstruation, lymphatic or haematogenous dissemination, coelemic metaplasia, spread of endometrial progenitor/stem cells, or other unclear autoimmune factors. Also could be iatrogenic from previous surgeries.
Anatomical pockets – pouch of Douglas, sigmoid mesocolon etc – may protect ectopic endometrial cells from normal peritoneal clearance.
- Up to 50 % of women with endometriosis are asymptomatic.
- Approximately 1 % of women diagnosed with pelvic endometriosis will have bladder or ureter involvement.
- 85 – 90 % urological endo is bladder, 10 % ureter, 4 % kidney, 2 % urethra.
Bladder involvement
May present with bladder pain, dysuria, cyclic haematuria, urinary frequency and UTIs.
Mean age 33, usually diagnosed during reproductive years (endometriosis typically regresses post menopause).
May be found incidentally on imaging.
Nodules seen well on ultrasound.
Cystoscopy:
- Classically oedematous, blue-ish submucosal lesions posterior to trigone or on the dome.
- Average about 1 cm, can be single or multiple.
Lesions may be intramural and not seen cystoscopically. They can be assessed with MRI.
Endometriosis is a histological diagnosis – requires biopsy or resection.
Treatment of bladder endometriosis
Medically therapy can be used first line if no hydronephrosis / severe symptoms.
- Oestrogen / progesterone
- OCP, With or without week placebo
- IUD
- Implanon
- GnRH agonists
Medical management precludes pregnancy.
Surgical management
- Laparoscopic or robotic excision of lesion / partial cystectomy
- Consider concurrent excision of all endometrial deposits in joint case.
- Complex excision is best to try prevent recurrence.
- Usual technique for partial cystectomy.
- Some techniques involve concomitant myometrial resection of adjacent uterus.
Ureteric involvement
Can be intrinsic or extrinsic – both can cause ureteric obstruction (often silent and asymptomatic).
Requires full history and examination and renal function testing.
Ultrasound and multiphase CT useful.
Will often have diffuse concurrent endometriosis.
MAG3 if indicated (+/- repeat MAG3 with stent in / obstruction relieved).
Any hydronephrosis should generally be treated with surgical intervention.
- Medical treatment may not resolve the fibrotic obstruction.
Manage as per any ureteric obstruction / reconstruction – generally excision of diseased segment and re-implant if distal, or ureterolysis can be considered if appropriate.
May need stent/nephrostomy acutely especially if infected.
Consider joint case with endometriosis surgeons and excise all other endometriosis.