The urinary tract is infiltrated in 14-20% of patients with deep infiltrating endometriosis¹. They often coexist with other endometriosis lesions. The most common symptoms are frequent urination, pain and burning on urination, strong desire to pass urine, blood in the urine and inability to fully empty the bladder. Some patients may have no symptoms at all. Diagnosis can be achieved by ultrasound and/or Magnetic Resonance Imaging (MRI).

In cases that do not respond to medication, surgical management (usually via laparoscopy) is generally indicated. The exact procedure employed depends on the part of the urinary tract affected by endometriosis:

1. Urinary Bladder: This is the site that is most commonly involved in cases of urinary tract endometriosis². The affected part of the bladder is removed laparoscopically and repaired with sutures. Often, protective stents are inserted in the ureters (the fine tubes that connect the kidneys to the bladder) that are removed post-operatively. A bladder catheter is also inserted and removed around 2 weeks post-surgery, after it has been confirmed that there is no leakage of urine.
2. Ureters: The fine tubes that connect the kidneys to the bladder (two in total, one on each side). Timely surgical management is important as, otherwise, the disease can lead to silent kidney loss. Most endometriosis lesions compress the ureter externally (extrinsic lesions) and can, therefore, be removed leaving the ureter intact. In the rare cases where the lesion is intrinsic, the affected part of the ureter is removed and the ureter sutured or a new entry of the ureter into the bladder is created, on the psoas muscle³. As mentioned previously, prophylactic ureteric stents are inserted and removed post-operatively. If ureteric stenosis has lead to a significant loss of kidney function, a laparoscopic nephrectomy can take place during the same surgery.

References:

1. Knabben L, Imboden S, Fellmann B, Nirgianakis K, Kuhn A, Mueller MD. Urinary tract endometriosis in patients with deep infiltrating endometriosis: prevalence, symptoms, management, and proposal for a new clinical classification. Fertil Steril. 2015; 103:147–152.
2. Maccagnano C, Pellucchi F, Rocchini L, Ghezzi M, Scattoni V, Montorsi F, Rigatti P, Colombo R. Diagnosis and treatment of bladder endometriosis: state of the art. Urol Int. 2012;89:249–258.
3. Carmignani L, Ronchetti A, Amicarelli F, Vercellini P, Spinelli M, Fedele L. Bladder psoas hitch in hydronephrosis due to pelvic endometriosis: outcome of urodynamic parameters. Fertil Steril. 2009 Jul;92(1):35-40.