Transvaginal sonography in diagnosis of vesicoperitoneal fistula due to deep infiltrating endometriosis as a cause of uroperitoneum

Ultrasonography has been proposed recently for use in the diagnosis of bladder endometriosis due to the presence of hypoechogenic or isoechogenic nodules in the bladder wall and nodules with heterogeneous echostructure containing numerous anechogenic (‘bubble-like’) areas1. This disease is associated with severe chronic pelvic pain, urgency and frequency, and often, also with dysuria, vesical tenesmus and hematuria in advanced stages of the disease2. No information is currently available in the literature regarding the role of transvaginal sonography (TVS) in the diagnosis of complications of anterior deep endometriosis. We report a case of a 42-year-old woman with acute onset of abdominal pain associated with nausea, vomiting and a distended abdomen. The patient had a medical history of chronic pelvic pain and 2 years earlier had suffered from dysuria. A cystoscopic examination performed at that time confirmed the presence of bladder endometriosis, which was treated by transurethral resectoscopic excision. Magnetic resonance imaging 2 months after surgery confirmed the persistence of bladder endometriosis with absence of free fluid in the peritoneum. On admission to our unit, transabdominal ultrasonography performed in the emergency room had demonstrated the presence of ascites in the absence of abdominal masses. Given the patient's previous diagnosis of endometriosis, TVS was also performed, which confirmed the presence of free fluid in the abdomen but also indicated the presence of a small nodule in the bladder wall and an interruption of a few millimeters of the wall near the vesicouterine pouch (Figure 1). An operative laparoscopy was performed to remove the uroperitoneum (urinary ascites), repair the vesicoperitoneal fistula and excise the endometriotic nodule (Figure 2). Pathological examination of the excised tissue confirmed the presence of deep infiltrating endometriosis in the bladder wall. Follow-up at 6 months indicated no recurrence. This is the first report of a case of uroperitoneum related to endometriosis; previously reported cases have been related to accidental trauma or iatrogenic injury or have been idiopathic. In the case reported here, it is possible that the transurethral resectoscopic excision of bladder endometriosis 2 years earlier may also have been a factor. Establishing an early diagnosis of this condition is crucial because failure to do so is associated with high mortality3. Urinary tract endometriosis is a relatively common condition, accounting for 19% of all patients with severe endometriosis4. One group of authors has argued that bladder endometriosis should be considered as bladder adenomyosis as they found, in a series of 17 cases, that approximately 90% of the nodules consisted of smooth muscle hyperplasia5. For this reason, and further confirmed by this case, transurethral resection is not recommended as a definitive treatment for bladder endometriosis because of the high recurrence rate and risk of bladder perforation6, 7. Laparoscopic treatment, without the need for ureteral cannulation, is considered to be the management of choice in uncomplicated bladder endometriosis8, and we feel that this is also the best approach in the presence of uroperitoneum or other complications. On the basis of this case, we suggest that in a patient with ascites and a history of endometriosis the possible presence of a vesicoperitoneal fistula should be considered. Indirect signs, such as sliding, obliteration of the vesicouterine pouch and pain on application of pressure with the probe9, 10, should also be evaluated with the aim of validating appropriate surgical treatment in a potentially life-threatening condition. S. Guerriero*, B. Piras, C. Peddes and E. Paladino Department of Obstetrics and Gynecology, University of Cagliari, Cagliari, Italy