Bladder endometriosis in a patient with undirected manifestations: a case report

Bladder endometriosis should be kept in mind as a differential diagnosis of bladder masses despite its rarity because this condition is connected with many symptoms that affect the patient’s quality of life and can cause infertility. Further studies are needed to understand the pathology of these lesions.

Endometriosis is defined as the presence of functional glands and stroma of the uterus outside its cavity [ 1 , 2 ]. It affects 10–20% of women of reproductive age, especially between 30 and 45 years [ 3 , 4 ]. It can form in different parts of the body, but the most affected locations are the ovaries, ovarian fossa, pouch of Douglas, uterosacral ligaments, and rectovaginal septum [ 1 ]. Involvement of the urinary tract is rare (1% of all cases) [ 1 , 2 ]. The most affected location of the urinary tract is the bladder (84%) [ 5 , 6 ]. Bladder endometriosis can be classified into primary (happening spontaneously) and secondary (iatrogenic, which can form after pelvic surgery) [ 1 , 3 , 6 ]. Many theories try to explain endometriosis, such as implantation theory, Celomic theory, lymphatic or hematogenous dissemination, inflammatory disease, endometriomas, and many others [ 1 , 7 ]. The main symptoms of endometriosis are pain-related ones and infertility [ 2 ]. The manifestations of bladder endometriosis, which vary a lot depending on the size and location, include suprapubic and back pain, hematuria, irritative voiding symptoms related to menstruation, dysmenorrhea, and dyspareunia [ 1 , 6 ]. A total of 60% of patients with bladder endometriosis experience symptoms without any relationship to menstruation, as in our case [ 4 ]. For diagnosing this disease, we depend on anamnesis, pelvic examination (uterine retroversion or painful uterine mobilization can be seen), radiological investigations, and laparoscopy. No serum marker can help us. Radiological investigations are essential. US imaging is a good method (sensitivity 83% and specificity 89%) [ 7 ]. It is suggested to do it either before or during menstruation because the lesions become clearer [ 5 ]. US imaging is less helpful in cases of deeply infiltrated endometriosis such as the bladder [ 7 ]. MRI is more helpful in such cases (its accuracy is about 98%). In addition, it helps determine the extent and severity of the disease [ 1 , 7 ]. Laparoscopy is the golden standard in the diagnosis of endometriosis, where we can take biopsies that confirm the histopathological nature of the lesion [ 2 , 7 ]. Many differential diagnoses should be kept in mind in addition to endometriosis, including subserosal anterior leiomyoma, bladder cancer, interstitial cystitis, and cystitis [ 4 , 8 ]. The management of the disease depends on medications and surgery. Drugs work by decreasing the estradiol levels in the serum, inhibiting ovulation, and reducing the blood flow in the uterus. They include danazol (not recommended recently), oral contraceptives, GnRH agonists, GnRH antagonists (elagolix), and hormonal receptor modulators (such as ulipristal). Laparoscopy, in addition to its important role in diagnosis, is a cornerstone method in treatment. It allows for excising all the lesions (including peritoneal ones of all types), excising endometriomas, and lysis of the adhesions. When the lesions infiltrate the bladder, they must be removed even when opening and suturing of the bladder is necessary, and attention should be given to the ureteral mouth involvement [ 7 ]. Bladder endometriosis can also be treated by transurethral resection and segmental bladder resection [ 6 ].

Endometriosis, a condition affecting approximately 10% of women in their reproductive years, is characterized by the presence of endometrial-like tissue outside the uterus. While commonly involving the ovaries or pelvic ligaments, endometriosis rarely affects the urinary tract, occurring in about 1% of cases. The bladder, particularly its posterior wall, is the most frequently involved site [ 1 , 2 ]. The exact cause of endometriosis remains unknown, but theories include retrograde menstruation and the spread of endometrial cells via the blood or lymphatic system try to explain it [ 1 ]. Women with urinary tract endometriosis may experience a variety of symptoms, including pelvic pain, dyspareunia, urinary urgency and frequency, dysuria, and hematuria, particularly during menstruation [ 3 ]. This report presents a case of bladder endometriosis with undirected manifestations and investigations, highlighting the importance of considering this condition in women presenting with urological and gynecological symptoms. A 37-year-old Syrian woman presented to the clinic with urinary hesitancy, dysuria, suprapubic pain, and intermittent hematuria for a year. The patient has experienced dysmenorrhea, irregular menstruation, dyspareunia, and pelvic pain for 3 years. According to the patient, these symptoms did not follow a specific pattern related to menstruation. Her medical history showed a urinary tract infection 1 year prior that did not respond to treatment and left lower extremity venous thrombosis 7 years ago. In addition, she was taking warfarin until now. Her surgical history included a laparoscopy for infertility due to adhesions 7 years prior and a cesarean section 5 years prior (after intracytoplasmic sperm injection). Her drugs (except warfarin), familial, and psychosocial histories were unremarkable. The laboratory findings included hematuria on urinalysis (red blood cells filling the microscopic field) and an international normalized ratio of 2.5. Other investigations, including complete blood count, kidney function tests, and liver function tests, were within normal. Ultrasound (US) imaging showed a mass on the posterior wall of the bladder; other findings were within normal. Computed tomography (CT) imaging revealed a 3 cm mass on the posterior bladder wall extending toward the uterus, raising the possibility of a bladder mass or a uterine mass involving the bladder (Fig.  1 ). A 5 cm functional cyst, likely benign, was also noted in the left ovary (Fig.  2 ). Pelvic magnetic resonance imaging (MRI) was performed using sagittal, coronal, and axial planes, both pre- and post-contrast injections. Imaging showed scarring from the previous cesarean section on the lower anterior uterine wall with associated uterine wall thinning. There was a thickening of the posterior bladder wall with a low signal on T2 (Fig.  3 ). Several small, high-signal T2 cystic spaces measuring approximately 23 × 16 mm demonstrated significant contrast enhancement. Enlargement of the posterior uterine wall near the cervix was noted, but no distinct masses were identified within the uterus. The ovaries appeared normal in size. Many differential diagnoses were made, such as uterine mass (fibroid or neoplasm), bladder neoplasm, bladder endometriosis, foreign body, and sarcoma. Although cystopanendoscopy (CPE) and diagnostic laparoscopy could have been useful in further characterizing the bladder mass before surgery, they were not performed. Given the clarity of the imaging findings and the clinical presentation, proceeding directly with surgical excision was deemed appropriate. This approach minimized unnecessary procedures, reducing both the financial burden and time commitment for the patient. The patient’s written consent and medical consultations were taken before the surgery, and they showed no contraindications. During the surgical procedure, which was done by a urologist, a Pfannenstiel incision was utilized, providing surgical access to the pelvic cavity. A solid mass was found on the posterior wall of the bladder and was excised (Fig.  4 ). Fig. 1 Computed tomography (horizontal plane) imaging revealing a 3 cm mass (red arrow) on the posterior bladder wall extending toward the uterus, raising the possibility of a bladder mass or a uterine mass involving the bladder Fig. 2 Computed tomography (horizontal plane) imaging revealing a 5 cm functional cyst (red arrow), likely benign, in the left ovary Fig. 3 Pelvic magnetic resonance imaging (horizontal plane) revealing scarring from the previous cesarean section on the lower anterior uterine wall with associated uterine wall thinning. There is a thickening of the posterior bladder wall (red arrow) with low signal on T2-weighted imaging Fig. 4 Picture showing surgical view after the excision of the endometriosis mass and its relation to the bladder trigone Computed tomography (horizontal plane) imaging revealing a 3 cm mass (red arrow) on the posterior bladder wall extending toward the uterus, raising the possibility of a bladder mass or a uterine mass involving the bladder Computed tomography (horizontal plane) imaging revealing a 5 cm functional cyst (red arrow), likely benign, in the left ovary Pelvic magnetic resonance imaging (horizontal plane) revealing scarring from the previous cesarean section on the lower anterior uterine wall with associated uterine wall thinning. There is a thickening of the posterior bladder wall (red arrow) with low signal on T2-weighted imaging Picture showing surgical view after the excision of the endometriosis mass and its relation to the bladder trigone The patient was discharged from the hospital after 2 days in a good situation and without complications. The histopathological examination of the excised mass revealed benign endometriosis. The patient’s manifestations were resolved after the surgery. Evaluations at 3 and 6 months post-surgery by cystoscopy were normal. She was followed for 2 years postoperatively without any recurrence.