Fistula is a pathological channel that connects hollow organs, natural or pathological cavities of the body with each other (internal fistula) or with the environment (external fistula). It is manifested by the presence of a fistula, through which mucus, pus, the contents of an organ or cavity are released: feces, urine, saliva, liquor, bile. It is diagnosed on the basis of clinical symptoms, fistulography data, and other instrumental and laboratory studies. With internal fistulas, endoscopic manipulations are performed. Treatment is determined by the type of pathology, can be conservative, operative, combined.
Meaning
Fistula are a large and very heterogeneous group of pathological conditions found in many areas of practical medicine. They have an innate or acquired character, arise as a result of the destruction of tissues of various genesis or are created artificially. They are often difficult to treat, in some cases they are life-threatening due to significant losses of fluid and nutrients. Urogenital and gastrointestinal fistulas have the greatest clinical significance due to their prevalence and possible consequences.
Fistula causes
The immediate cause of the formation of fistulas are disorders of the formation or destruction of organs and tissues. Taking into account the etiology , the following groups of fistulas are distinguished:
- Congenital. They appear as a result of fetal development disorders, which may be caused by hereditary diseases, the impact of unfavorable external and internal factors.
- Acquired pathological. They are formed against the background of inflammatory processes, wounds, damage to the walls of hollow organs by foreign bodies, destruction by malignant tumors, chemicals, radiation exposure. Sometimes they become a complication of surgical treatment of various pathologies.
- Acquired artificial (stomas). They are specially created operationally to preserve vital activity in case of violation of the passage of the contents of hollow organs (chyme), secretions (bile) or excreta (feces, urine), to ensure the intake of nutrients into the body.
Pathogenesis
Congenital fistulas are the result of underdevelopment or improper development of organs and body parts. Since they are formed naturally, their walls are covered with epithelium. Acquired fistulas appear when the contents break through, accompanied by the destruction of already formed tissues. The walls are represented by granulations, outside, as a result of scarring, a layer of dense connective tissue is formed over time.
A special group are lip-shaped fistulas, in which the epithelium of the mucosa passes into the epithelium of the skin. They belong to the epithelized, but are created artificially. Epithelized fistulas do not close on their own. Granulating fistulas are capable of healing when the process (usually inflammatory) is eliminated, which supports the outflow of contents through the channel.
Classification
Currently, researchers, as well as specialists in the field of surgery, use the following systematization of fistulas:
- By origin: congenital, acquired (pathological and artificial).
- By structure: epithelized, granulated, lip-shaped.
- In relation to the environment: external (connect the cavity with the external environment), internal (connect two cavities).
- By localization: gastric, intestinal, rectal, tracheoesophageal, bronchial, levovaginal, rectovaginal, parotid.
- According to the type of discharge: mucous, purulent, fecal, urinary, liquor, etc.
Fistula symptoms
A common sign of the disease is the presence of a pathological communication between two or more cavities or the body cavity and the environment. With external fistulas, an opening (stroke) is revealed during the examination. The edges of the hole are inflamed, macerated due to skin irritation. The amount and nature of the discharge vary depending on the type of fistula, the features of the pathological process.
Internal fistulas are manifested by the presence of an atypical discharge from a natural opening. Significant losses of fluid and nutrients in some types of fistulas cause exhaustion, gross violations of all types of metabolism, which can lead to the death of the patient.
Digestive system fistulas
They can form throughout the gastrointestinal tract, from the esophagus to the rectum, be external or internal. Gastric fistulas are usually of artificial origin (gastrostoma), esophageal fistulas are provoked by a pathological process, intestinal fistulas are artificial (colostomy, ileostomy, cecostomy) and pathological. The first place among the causes of the formation of esophageal fistulas is occupied by tumors, intestinal – the failure of anastomoses.
The formation of external fistulas is accompanied by the appearance of infiltrate. With internal fistulas, the clinical picture resembles a perforation of a hollow organ. With tracheoesophageal anastomoses, pieces of food are coughed up from the upper respiratory tract. Internal gastrointestinal fistula is manifested by fecal vomiting, fecal odor from the mouth. With an externally formed fistula on the skin, a course with esophageal, gastric or intestinal discharge is detected, with an unformed one – a purulent wound, at the bottom of which the loop of the intestine, the wall of the stomach is visible.
Diarrhea, vomiting, and auto-intoxication are typical. The rate of exhaustion and the development of metabolic disorders depends on the diameter of the fistula – the wider it is, the faster the symptoms worsen. Dehydration, exhaustion, protein-free edema, anemia are possible. Intoxication, metabolic disorders lead to changes in the liver and kidneys. In severe cases, renal and hepatic insufficiency develop.
Gallbladder fistulas
Biliary fistulas usually become a complication of cholelithiasis, they can be external or internal, they can connect the biliary tract with the stomach, intestine, pleural cavity, bronchus. External fistulas are accompanied by the formation of a hole with a bile or purulent discharge, internal – symptoms of cholangitis, diarrhea, weight loss, intoxication.
Rectal fistulas
They include various forms of paraproctitis and rectovaginal fistulas. Paraproctitis occurs with purulent inflammation of the intestinal wall and pararectal fiber, manifested by pain, foreign body sensation, general symptoms of intoxication. Pus is released from the anus or a hole with a purulent discharge is found on the skin of the perianal zone. With rectovaginal fistulas, gases and feces are released from the vagina. Frequent pain in the perineum, inflammatory diseases of the genitals, urinary tract.
Urogenital fistulas
They are formed between the genitals and the urethra, ureters or bladder. They develop after severe and complicated childbirth, surgery, and radiation therapy. The most common are urethro-vaginal and vesicovaginal fistulas. Vesicular-uterine, ureteral-vaginal and other variants are less common.
Accompanied by leakage of urine from the genitals, the appearance of blood in the urine during menstruation. Usually painless. They do not pose a threat to life, but they significantly reduce its quality and cause social maladaptation. They are of great clinical importance due to the high prevalence (0.6-2%).
Bronchial fistulas
They occur more often after lung operations, are characterized by the appearance of communication with the skin, pleural cavity or hollow organs – esophagus, stomach, intestines, gallbladder. They are manifested by shortness of breath, cough, discharge of pus or atypical contents (food, bile) from the respiratory tract, weakness, sweating, and an increase in body temperature.
Ligature fistulas
Ligature fistula is a frequent complication (up to 5%) of surgical interventions, especially during operations on the organs of the abdominal cavity, pelvis. It develops due to the rejection of non-absorbable threads that are located deep in the tissues. During the formation period, pain, intoxication are noted, after the formation of a fistula, the condition normalizes. Fistulas are prone to chronic recurrent flow until the moment of removal or independent withdrawal of the thread.
Complications
The most common complications of any fistula are purulent and non–purulent inflammatory processes, including the formation of abscesses and swelling with damage to neighboring anatomical structures, chronic inflammation of various organs (cystitis, vaginitis, proctitis). In severe cases, sepsis is possible.
Fistulas significantly worsen the quality of life, often cause disability, negatively affect socialization. With external fistulas, dermatitis often develops, a cosmetic defect is formed. With complete fistulas of internal organs, cachexia, multiple organ failure is observed.
Diagnostics
Taking into account the localization of the fistula, the diagnosis is made by doctors of various specialties – surgeons, gynecologists, urologists, etc. In the process of diagnosis and determination of the treatment plan, the medical history, clinical symptoms, and data from additional studies are taken into account. The survey plan includes:
- Collecting anamnesis. Anamnesis often reveals operations or chronic diseases. The formation of external fistulas is preceded by the appearance of pain, infiltration, which is opened with the release of pus, and then the contents of a particular organ. The formation of internal fistulas is accompanied by pain, intoxication, and other symptoms depending on the location of the fistula.
- External inspection. If there is a hole in the skin, the involved organ is determined by the nature of the discharge, and the size of the fistula is determined by the amount of discharge. Assess the general condition of the patient, identify signs of exhaustion, dysfunction of various organs.
- Samples with dyes. Sometimes methylene blue and other solutions are used to clarify the localization of the fistula, determine the number of strokes, and detect congestion, which are given orally or injected into a natural hole.
- Laboratory tests. When studying the discharge, bilirubin, amylase, urea and other compounds can be detected, which in doubtful cases makes it possible to confirm damage to a certain organ.
- Fistulography. It is the most common imaging method for diagnosing external fistulas. Contrast is injected into the hole, according to the images, the affected organ is determined, the exact localization of the fistula, the direction of travel, the presence of congestion.
- Radiography with contrast. In case of internal lesions, irrigation, radiography of the stomach or esophagus with barium is performed. The contrast goes through the wall of the organ to the skin, to neighboring organs or cavities, which allows you to clarify the features of the fistula.
- Endoscopic examinations. To identify fistulas, determine their location and the diameter of the holes, gastroscopy, colonoscopy, bronchoscopy, cystoscopy, etc. are performed.
Some internal fistulas present significant diagnostic difficulties, they are detected only during surgical interventions. Differential diagnosis is carried out between different types of fistulas, with inflammatory diseases, and other pathological processes.
Fistula treatment
Treatment tactics are determined by the type of fistula. Granulating fistulas can close against the background of conservative therapy, with epithelized recovery is possible only after surgical intervention. Along with the elimination of the underlying pathology, correction of metabolic disorders, competent care of the hole plays an important role.
Conservative therapy
A prerequisite for the closure of the fistula is the elimination of the cause of its appearance. If it is impossible to influence the etiological factor, the goal of therapy is to prepare the patient for surgery. Treatment involves general and local activities. It is shown in the case of all types of fistulas – both epithelized and granulating. Includes:
- Fistula care. It is necessary to regularly toilet the skin around the hole, lubricate the skin with protective pastes. With artificial fistulas, training of the patient in the use of urine and colostomy bags is required.
- Limiting the selection of content. With some localizations of fistulas, for example, their rectovaginal location, the closure of the fistula passage in some cases can be achieved by unloading the intestine against the background of enemas, a special diet.
- Other local impacts. Washing with chemical solutions, the use of enzymatic preparations, and local autohemotherapy can be effective. Tissue regeneration is stimulated by injections of collagen gel with fibroblasts.
- Correction of general violations. With significant losses of protein, water and electrolytes, the preparation of an individual diet, infusion therapy with the introduction of albumin, salt solutions, and other compounds is indicated.
- Anti-inflammatory therapy. In case of secondary infection, antibacterial drugs, immunocorrectors, detoxification agents are prescribed.
Surgical treatment
Surgical interventions are performed with epithelized, formed granulating, spongy fistulas. Taking into account the peculiarities of the location of the fistula and the condition of the surrounding tissues, the following operations are performed:
- Excision of the fistula. It is produced after staining with methylene blue or another solution, which allows you to accurately determine the features of the course, to identify the congestion. The stroke is removed together with the surrounding altered tissues, the wound is sutured, drained.
- Excision with defect replacement. Sometimes, after the removal of the altered area, there is a shortage of tissues, or when stitching the tissues, their excessive tension is observed. In such cases, the fistula is closed by transposition of a skin-muscle or muscle flap, adipose tissue on the vascular pedicle.
- Resection of the organ. With some fistulas of hollow organs, for example, with intestinal ones, partial excision of the organ is the best option. The operation can be carried out in one or two stages. In the second case, a bypass anastomosis is pre-imposed for unloading by stopping the passage of the contents.
Removal of altered tissues is often supplemented with actions aimed at preventing the re-formation of a fistula. To do this, fascia sections and mesh implants are placed between the separated cavities. In the postoperative period, standard therapeutic measures are carried out – bandages, antibiotic therapy, analgesic therapy.
Forecast
The prognosis is determined by the localization, type and time of existence of the fistula, the prevalence of changes in surrounding tissues, the nature of the underlying pathology, the degree of violation of the homeostasis of the patient’s body, the presence of concomitant diseases. Fistulas, even granulating ones, rarely respond to conservative treatment. After excision, recovery is often observed. With some types of fistulas accompanied by severe metabolic disorders, especially with high gastrointestinal, a fatal outcome is possible.
Prevention
Preventive measures include timely treatment of diseases that can lead to the formation of fistulas. It is necessary to prevent the occurrence of infections in the area of wound canals, observe the technique of applying anastomoses, ensure the unloading of operated organs at the stage of preparation for intervention and postoperative recovery.