Vesicovaginal fistula is a pathological communication between the vagina and the bladder cavity. It is manifested by constant liquid vaginal discharge, hematuria during menstruation, dysuric disorders, soreness over the pubis, dyspareunia. For diagnosis, examination in mirrors, colposcopy, cystoscopy, intravesical administration of enzymes, intravenous urography, retrograde cystography, vaginography, CT, MRI are used. Pathology treatment of vesicovaginal fistula is operative with transvaginal, transabdominal or reconstructive fistuloplasty.
ICD 10
N82.0 Vesicovaginal fistula
General information
The prevalence of vesicovaginal fistulas (fistulas) is 0.3-2% and differs significantly in different countries. Higher rates were recorded in States with poorly accessible or substandard medical care. 9 out of 10 cases of the disease are iatrogenic complications that occur after pathological childbirth or surgical interventions on the pelvic organs. The urgency of timely diagnosis and treatment of the disorder is associated with a significant deterioration in the patient’s quality of life, a violation of sexual and reproductive function, and a high risk of relapse after late surgery on fibrotic-altered tissues.
Causes of vesicovaginal fistula
The communication between the bladder and the vagina occurs due to the destruction of the walls of organs during injuries and pathological processes in the pelvic cavity. Specialists in the field of gynecology and urology distinguish several groups of traumatic, inflammatory and destructive causes that lead to the formation of urinary-vaginal fistulas. The main ones are:
- Gynecological surgical interventions. Up to 70% of vesicovaginal fistulas result from hysterectomy in benign uterine fibromyomas. Unintentional injuries during cesarean section, surgical treatment of endometriosis, uterine cancer, and other pelvic organ diseases also lead to their formation.
- Pathological childbirth. Prolonged compression of the soft tissues of the birth canal during prolonged labor, secondary weakness of the birth forces, passage of a large fetus, a narrow pelvis of the mother causes ischemic necrosis with subsequent formation of a fistula. Traumatic injuries occur with improper application of forceps and tissue ruptures.
- Accidental injuries. In a small number of cases, vesico-genital fistulas are formed after traumatic tissue ruptures due to road accidents, accidents at work and at home, rape. Possible perforation of the walls of the vagina, bladder during masturbation with the introduction of sharp objects into the vagina or urethral canal.
- Oncological diseases of the reproductive organs. The walls of the vagina, bladder can be destroyed due to the germination of a tumor in cervical cancer, vagina, and other malignant neoplasms. Fistula passages formed after radiation therapy of oncological pathology are considered to be one of the most difficult to treat.
- Inflammatory processes. Pelvic abscesses may break out into the vagina, bladder, and form fistulas. Fistulous passages between these organs appear due to damage to their walls in some infectious diseases — venereal lymphogranuloma, schistomatosis, actinomycosis, tuberculosis of the urinary organs.
Pathogenesis
The initial stage of the formation of vesicovaginal fistulas is the perforation of the tissues that separate the vagina and bladder. If such damage was not noticed and sutured in time, the existing pressure difference between the organs and the constant leakage of urine do not allow the hole to be scarred. As a result, a fistular course lined with epithelial tissue occurs in 7-14 days. The situation is aggravated by the presence of inflammatory or destructive processes in the area of the fistula canal. In 65-66% of cases, urinary-vaginal fistulas appear in the first 10 days after injury, and finally form in 3-5 months.
Classification
The modern systematization of vesico-vaginal fistulas most fully reflects the characteristics of fistulas and is an effective tool for choosing the optimal surgical intervention, predicting the features of the postoperative period. The classification is based on three key criteria that make it possible to fully describe the fistula:
- The length of the fistula. Depending on the distance between the outer and inner opening, fistulas are distinguished with a length of more than 35, 26-35, 15-25, shorter than 15 mm.
- The diameter of the fistula canal. The indicator is estimated by the maximum diameter of the vesicovaginal fistula and can be up to 15, 15-30, more than 30 mm.
- The stage of scarring. There are fistulas without fibrosis or with its initial manifestations, moderate or severe fibrosis, special circumstances (post-radiation changes, etc.).
It is also recommended to take into account the scarring of the organs between which the urogenital fistula has formed. With initial violations, the length of the vagina is not changed or is not less than 6.0 cm, the capacity of the bladder is preserved. A more complex disorder is indicated by a shortening of the vagina less than 6 cm and a decrease in intravesical capacity.
Symptoms of vesicovaginal fistula
In some patients, the only complaint is an increase in the amount of liquid vaginal discharge and the appearance of blood impurities in the urine during menstruation. With a large fistula opening, self-urination stops completely, and all urine continuously flows through the vagina with a virtually empty bladder. Irritation of the perineum due to leakage of urine causes itching and ulceration of tissues. The addition of secondary inflammatory processes is manifested by increased urination, pain and pain in the urethra. There may be painful sensations in the suprapubic region. Scarring of the tissues around the fistula is often accompanied by a narrowing of the vagina, a decrease in the elasticity of its walls, which provokes pain during sexual intercourse.
Complications
With a fistulous connection of the bladder and vagina, the likelihood of chronic inflammatory diseases of the urinary organs (cystitis, urethritis) increases, including an ascending infection that causes ureteritis and pyelonephritis. The flow of urine into the vaginal cavity is often accompanied by a change in the acidity of vaginal secretions, the development of vaginosis, colpitis, exocervicitis. In turn, this increases the risk of endocervicitis, endometritis, salpingitis, adnexitis caused by activated opportunistic flora. The probability of neoplastic processes increases. Often, women’s sexual life is disrupted, infertility occurs. The presence of persistent secretions with a characteristic odor, itching in the genital area worsen the quality of life of patients, provoking neurotic disorders — neurotic excoriation, hypochondria, subdepressive states.
Diagnostics
The tasks of the diagnostic stage in case of suspected vesicovaginal fistula are to confirm the pathological message of the organs and a clear localization of the mouth of the fistula canal. For this purpose, visual inspection and various instrumental techniques are used, based on the identification of a passage of a coloring or contrast agent or a layer-by-layer study of tissues. Recommended diagnostic methods include:
- Examination on the chair. A small fistula opening on the front wall of the vagina is usually invisible. The defect is well detected with large sizes, necrotic or inflammatory changes in the surrounding tissues, their “encrustation” with urinary salts. The search for a fistula simplifies stretching the walls of the vagina with cylindrical or grooved mirrors, followed by probing the fistula course. If necessary, the examination is supplemented with colposcopy.
- Cystoscopy. Endoscopic examination of the cavity and walls of the bladder is aimed at detecting the fistula opening, assessing its size, determining localization. Additionally, possible inflammatory changes of the mucosa, scar deformities, the presence of stones and ligatures are revealed. The results of cystoscopy make it possible to more accurately select the type and scope of surgical intervention to eliminate abnormal inter-organ communication.
- The use of coloring and contrast agents. Transurethral injection of pigments into the bladder or taking drugs that stain urine, with simultaneous insertion of a tampon into the vagina, allows you to confirm the presence of a fistula and approximately determine the location of its localization. More accurate ways to detect atypical ways of urine outflow are intravenous urography, retrograde cystography and vaginography using X-ray contrast agents.
- CT and MRI of the pelvic organs. Magnetic resonance and computed tomography studies provide an opportunity to study in detail the structure of organs and identify anatomical defects in their walls. The resulting layered sections or 3D model accurately reflect the location of the urinary-vaginal fistula, the size and structural features of the fistula course. Such data are especially valuable when choosing a method of surgical plastic surgery.
Since the disorder is often complicated by other urogenital diseases, it is important to identify possible disorders of the reproductive and urinary systems at the diagnostic stage. To screen for such complications, ultrasound of the pelvic organs and kidneys is usually performed, general urine and blood tests are performed, the level of creatinine, urea and uric acid in the blood is determined. In addition to the gynecologist, a urologist is usually involved in the management of the patient. If necessary, the patient is consulted by a nephrologist, surgeon, oncologist. Differential diagnosis is carried out with specific colpitis, endocervicitis, endometritis, in which there is an increase in the volume of vaginal discharge, spontaneous emptying of the hydrosalpinx, urinary incontinence, acute urethritis, cystitis.
Treatment of vesicovaginal fistula
No drug therapies for the disorder have been proposed. Spontaneous healing of the fistula connecting the vagina with the bladder is observed in 2-3% of sick women with a small size of the fistula opening. The acceleration of regeneration processes in such cases is facilitated by the removal of urine using a permanent urethral catheter. In some patients, coagulation of the edges of the fistula with electric current or silver preparations from the vagina or bladder is effective. In other cases, one of the surgical interventions to restore the damaged vaginal wall is recommended.
According to the majority of urogynecologists, delayed fistuloplasty, which is performed 4-6 months after the formation of a fistula, is most justified. During this time, the inflammatory processes caused by the traumatic effect subside as much as possible, high—quality preoperative preparation can be carried out – ligature stones are removed, the bladder and vagina are sanitized, blood supply to tissues is restored. When choosing a specific technique, the size and location of the fistula, the presence of cicatricial changes, the distance from the mouths of the ureters, the elasticity of the vaginal walls are taken into account. The most common:
- Vaginal excision of the fistula. The operation is characterized by physiology, low traumatism, preservation of the integrity of the bladder, a simpler way of suturing the fistula course, relatively rapid recovery and the absence of severe complications. The method is indicated for excision of small uncomplicated fistulas with good mobility and extensibility of vaginal tissues. The limitations for such operations are gross scarring of the vagina and the deep occurrence of the fistula canal, the removal of which may damage the intravesical area with the mouths of the ureters.
- Transabdominal excision of the fistula. Closure of the defect through an incision of the anterior abdominal wall and bladder is indicated in the presence of large-sized fistulas, involvement of the ureters, detection of combined fistulas, concomitant intestinal pathology. With a higher injury rate, the advantages of the method are considered to be good access and sufficient visibility for effective removal of altered tissues, preservation of normal urodynamics after surgery, the possibility of eliminating even relatively large and complex defects with high-quality suturing of the organs involved.
- Reconstructive plastic surgery. The most difficult operations are to restore the integrity of the vesicovaginal septum after radiotherapy. In such patients, the tissues surrounding the fistula are fibrotic, inelastic, has limited vascularization and heal poorly. The defect is closed by tissue interposition with a graft — a fragment of a thin or small thigh muscle, a fibrous-fat flap from the labia majora, a peritoneum, a serous-muscular intestinal flap, a segment of the omentum or gastric wall. The operation requires careful preparation in order to avoid relapse.
Prognosis and prevention
The risk of recurrent fistula formation after surgical treatment can be reduced due to proper preoperative preparation and compliance with the intervention technique. The highest recurrence rate — from 15% to 70% — is observed in post-radiation vesicovaginal fistulae. With traumatic fistulas, the effectiveness of fistuloplasty reaches 92-96%. Pregnancy planning after surgery is allowed no earlier than 1.5-2 years after delivery by caesarean section. In order to prevent the disorder, regular examinations by a gynecologist are recommended for early detection of diseases requiring surgical treatment, timely registration to reduce the risk of complications in childbirth, careful management of childbirth, technically accurate performance of gynecological, urological operations.
