Ureterovaginal fistula is a pathological communication of the lumen of the ureter and the vaginal cavity, disrupting the natural passage of urine. It is manifested by involuntary urination through the vagina with preserved or disturbed natural urination. It is possible to develop pain syndrome in the lumbar region and hyperthermia. It is diagnosed by gynecological examination, ureteral catheterization, X-ray and endoscopic examinations of the urinary tract, CT, MRI. Ureteral stenting, Boari surgery, ureterocystoneostomy, intestinal plastic surgery are used for treatment.
N82.1 Other fistulas of the female genitourinary tract
In the structure of urogenital fistulas, ureterovaginal fistula occupy 25-30%. Most often they are diagnosed in women who have undergone radical interventions with the removal of the uterus or rectum. According to the results of research in the field of modern urology, obstetrics and gynecology, traumatic damage to the ureters with the formation of fistula passages and urinary discharge into the vagina is observed in 3-15% of such patients.
The urgency of timely detection of a fistula is due to the frequent destruction of the renal parenchyma due to a violation of the natural passage of urine. However, only 20% of cases of ligation, suture inflection, complete or partial intersection, detachment, compression, devascularization of the ureter are detected intraoperatively, and 15% of fistula reports are not clinically manifested during the first month after surgery.
The formation of a pathological junction between the ureter and the vagina is caused by damage to the walls of these organs or a violation of their development in embryogenesis. According to clinical observations, most ureterovaginal fistula have a traumatic origin. Among the reasons leading to the occurrence of a defect are:
- Radical operations on pelvic organs. Fistulas are formed when the technique of interventions is violated or combined with radiation therapy. Ureteral-vaginal anastomoses are formed at the intersection of the ureters or their necrosis in violation of the technique of surgical isolation from surrounding tissues. More often, fistulas are detected in women who have undergone hysterectomy due to uterine cancer, fibroids, common infiltrative endometriosis, parametritis, tubovarial abscess, uterine rupture in childbirth, less often — after removal of the rectum, cesarean section.
- Oncological and inflammatory diseases. Communication between the urethral lumen and the vagina can occur with the tumor destruction of these organs, germination and decay of some types of malignant tumors. The probability of defect formation increases in women with cancer of the ovaries, body and cervix, bladder, kidneys, rectum. Radiation therapy of pelvic malignant neoplasia becomes an additional risk factor. In rare cases, spontaneous perforation of an abscess localized in the pelvis leads to the formation of a fistula.
- Congenital ectopia of the ureter. Ureterovaginal fistula are a rare variant of dysembriogenetic urogenital fistulas. They are detected in 25% of congenital ureteral ectopias. Abnormal development of germ leaves is usually caused by the influence of teratogenic factors at 3-8 weeks of pregnancy. Possible causes of embryogenesis disorders may be exposure to chemicals (medicines, industrial and household poisons), infectious agents, endogenous intoxication with exacerbation of chronic processes.
Due to the wider use of laparoscopic interventions in recent years, fistulas that have arisen as a result of thermal damage to the ureteral membranes during vascular coagulation have become more common. According to various authors, the pathological communication of the vagina with the ureter occurs in 0.47% of patients who have undergone laparoscopic hysterectomy.
After pathological childbirth with obstetric interventions and ruptures of the birth canal, uretero-vaginal messages are formed much less frequently than urethro-vaginal and urinary-vaginal. In some cases, fistulas are the results of direct traumatic tissue damage in road accidents, industrial accidents, falls from a height, penetrating piercing and gunshot wounds of the pelvic organs.
In case of accidental crossing of the ureter or necrosis of its wall due to radiation exposure, tumor destruction, blood supply disorders due to separation over a long distance, urine begins to flow into the surrounding tissues. Its outflow into the vagina can be facilitated by the failure of postoperative sutures, damage by a sprouting tumor, X-rays. Constant urination prevents the restoration of tissue integrity. Within 10-21 days, a fistula lined with epithelium is formed between the vagina and the ureter, less often with granulation tissue.
The mechanism of formation of a ureterovaginal fistula in congenital ectopia of the mouth is due to a violation of the migration of mesodermal ducts to the site of a typical confluence with the urea and their implantation into the vagina. Depending on the features of traumatic injury or disorders of embryogenesis, fistulas can be unilateral and bilateral (bilateral).
A sign of a pathological communication of the vagina and ureter is usually an involuntary leakage of urine from the vagina with preserved urination. The bilateral lesion is characterized by urination only through the vagina with the absence of natural urination. With unilateral postoperative fistulas, the appearance of vaginal discharge is often preceded by acute unilateral pain in the lumbar region and transient hyperthermia up to 38-39 ° C, caused by a violation of the outflow of urine from the kidney on the affected side. After the formation of a fistula course, which often occurs by the end of 2-3 weeks of the postoperative period, the pain syndrome and temperature reaction pass.
Ureterovaginal fistula messages are often complicated by ascending infection of the kidneys. As a result of the penetration of pathogenic or conditionally pathogenic microorganisms, patients develop pyelonephritis, which, in the absence of adequate therapy and immune disorders, can lead to kidney destruction, the occurrence of peritonitis and urosepsis. Accumulation of urine in the area of the defect leads to the formation of paraureteral urinoma.
With narrowing of the ureteral lumen at the confluence with the vagina, the outflow of urine worsens, which is accompanied by the development of ureterohydronephrosis, and subsequently — chronic renal failure. Constant vaginal urination reduces the quality of intimate life, irritates the mucous membranes, disrupts the normal reaction of vaginal secretions, provokes the onset of inflammatory processes (colpitis, bacterial vaginosis, vulvitis, urethritis).
Diagnostic search for suspected ureteral-vaginal fistula is aimed at identifying the fistula, determining its exact localization and topography, and a comprehensive assessment of the functional state of the urinary organs. The following research methods are recommended for patients with complaints of liquid vaginal discharge with the smell of urine:
- Gynecological examination. When examined with the help of mirrors, it is often possible to visualize the fistula opening in the area of the arch (stump) of the vagina. Its detection is facilitated by funnel-shaped retractions and rhythmic urination. In the presence of gross cicatricial changes, the detection of a fistula may be difficult. In some cases, during vaginal examination through the fistula, it is possible to catheterize the ureter and even the renal pelvis.
- Endoscopic examination. Cystoscopy is informative for differential diagnosis with vesicovaginal fistulas. The mouth of the affected ureter with a complete fistula looks motionless, with an incomplete one it occasionally decreases, the release of dye during an indigo—carmine test is disturbed or absent. Chromocystoscopy is combined with the insertion of a tampon into the vagina and, if possible, supplemented with ureteroscopy.
- Catheterization of the ureter. Usually, the introduction of a catheter is difficult or impossible due to the presence of an obstacle at a distance of 3-5 cm from its mouth, which can sometimes be overcome with incomplete fistula. In some cases, it is possible to penetrate through the fistula into the vagina. In order to exclude passage into the parametrium, catheterization of the ureter is recommended to be performed under X-ray control. To identify the level of lesion, the study is combined with retrograde ureteropyelography.
- Excretory urography. Intravenous urography allows you to detect narrowing and fibrosis in the area of injury, enlargement of the ureter and renal pelvis, detect a decrease in excretory function of the kidneys. With a non-functioning kidney, antegrade pyeloureterography is additionally performed, aimed at obtaining more accurate information about the anatomical and topographic features of the fistula, ureter, pelvis.
In difficult cases, to exclude vesicovaginal fistula passages and to identify combined ureteral-vesicovaginal fistulas, a test is performed with two dyes – carmine instilled into the bladder and indigocarmine injected intravenously. To clarify the anatomical localization of the fistula and the features of the structure of the fistula, vaginography, MRI, CT are additionally prescribed.
Since renal function is often impaired with ureterovaginal fistula, biochemical blood and urine tests, Rehberg and Zimnitsky samples, and nephroscintigraphy are recommended. With the help of X-ray cinematography, the contractility of the ureter and pelvis is evaluated. Conducting a general urine analysis and sowing for microflora allows you to detect the inflammatory process in time.
Ureterovaginal fistula differentiate with various types of urogenital fistulas, vaginitis, bacterial vaginosis, endocervicitis, other inflammatory diseases of the genital organs, benign and malignant neoplasia of the vagina and uterus. The patient is shown consultations with a urologist, nephrologist, oncologist, infectious disease specialist, dermatovenerologist.
Despite the fact that it is sometimes possible to independently close the fistular uretero-vaginal communication, long-term waiting tactics are often complicated by inflammatory or scar-atrophic destruction of the renal parenchyma. Conservative management of the patient is allowed only in the presence of severe concomitant pathology, excluding surgical intervention, or preserved integrity of the ureter along the entire length, confirmed by the results of pyelography.
If damage to the ureteral wall is detected before scarring (within 6-8 days after surgery or injury), it is possible to heal the wound on a permanent ureteral catheter (stent) installed through the bladder or antegrade. At the same time, corticosteroid and resorption drugs are prescribed to soften scar tissue, in addition, unloading of the kidney through an imposed nephrostomy is possible. If conservative therapy is ineffective and hydronephrosis is detected, surgical methods of treatment are recommended:
- Ureterocystoanastomosis. With the location of the fistula in the juxtavesical region, reimplantation of the ureter into the bladder wall is possible – the imposition of ureterocystoanastomosis. During the operation, the area that communicates with the vagina is removed, the remaining part is carried out in the submucosal tunnel of the urea wall, a new mouth is formed.
- Operation Boari. It is performed when the entire pelvic ureter is destroyed and its length is insufficient to create a new ureterocystoanastomosis. During Boari surgery, after removal of damaged tissues from the bladder, a flap is excised, the missing ureteral part and ureteral-vesicular anastomosis are formed.
- Ureteroplasty. Intestinal ureteral plastic surgery is recommended for women with significant organ damage or sharply reduced bladder capacity. To restore the normal passage of urine, an isolated segment of the small intestine is used, replacing a defect of one or both ureters.
An alternative intervention if it is impossible to quickly restore normal urination with the help of these operations is autotransplantation of the kidney with its reduction to the pelvis, and with significant destruction of renal tissue — nephrectomy. To prevent possible infectious complications in the postoperative period, antibiotic therapy is performed.
Prognosis and prevention
The effectiveness of conservative treatment of ureteral-vaginal fistula messages reaches 10-12%, surgical methods — 90-93%. Primary prevention is aimed at regular visits to an obstetrician-gynecologist for timely detection of genital pathology, radical surgical treatment of which may be complicated by the formation of urogenital fistulas. An important role is played by the observance of the technique of interventions — the preservation of blood supply to the ureters due to the refusal of their separation from the posterior leaf of the broad ligament of the uterus, the formation of a new ureterovesical anastomosis in case of accidental intraoperative intersection of the organ.