Inflammatory fistulas: causes, symptoms, diagnosis, treatment

Causes of inflammatory fistula development: incorrect tactics of management of patients with purulent diseases of the pelvic organs. In patients with a long and recurrent course of the purulent process with untimely surgical treatment, with the next activation of the process, perforation of the abscess occurs (usually multiple times) into hollow organs and (or) the anterior abdominal wall (in patients with complications after previous operations). The formation of appendovaginal fistulas is facilitated by multiple punctures or colpotomies in patients with complicated forms of purulent inflammation.

[ 1 ], [ 2 ], [ 3 ]

Intestinal fistulas

Symptoms

The following symptoms are characteristic of the condition of pre-perforation of an abscess into the distal parts of the intestine:

• constant pain radiating to the rectum, lower back, navel, lower limbs;
• painful peristalsis;
• loose stools, sometimes with an admixture of mucus, which is sometimes interpreted as a manifestation of dysbacteriosis against the background of massive antibacterial therapy;
• tenesmus;
• sharp pain and “tension” of the purulent formation during bimanual and rectovaginal examination.

In case of perforation of the abscess into the intestine, patients experience tenesmus and abundant discharge of mucus from the rectum, then abundant, foul-smelling, liquid, purulent discharge from the rectum, which is accompanied by an improvement in the general condition of the patient. Often this is regarded as recovery and the patient is discharged from the hospital. However, it is necessary to remember that even in the presence of a fistula, complete emptying of the purulent formation of the uterine appendages does not occur. The inflammatory formation remains, the fistula tract, always tortuous, is obstructed rather quickly, which leads to another relapse of the inflammation.

A characteristic feature of a functioning fistula is a remittent course with periodic exacerbation of the inflammatory reaction and the release of pus with feces.

Diagnostics

A recto-vaginal examination is mandatory, in which case it is necessary to determine the possible prolapse of the infiltrate or abscess towards the rectum, and also to assess the condition of the mucous membrane above it (mobile, limited mobility, immobile) - these signs reflect the fact and degree of involvement of the rectal wall in the inflammatory process. It should be noted that it is impossible to establish the location of a possible perforation by palpation, since such perforations occur mainly in the lower third of the sigmoid colon and the rectosigmoid angle. In the presence of a functioning appendicointestinal fistula and palpation of the appendage, an admixture or a significant amount of purulent discharge is detected during a rectal examination.

The most informative methods for diagnosing appendicointestinal fistulas are ultrasound and computed tomography.

The following echographic signs may indicate the risk of formation of appendicointestinal fistulas:

1. destruction of the capsule of the inflammatory formation at the site of intestinal adjacency (with contrasting of the latter);
2. decreased echogenicity of the tissue in the affected area;
3. the tubo-ovarian formation is closely fused with the adjacent section of the intestine - the abscess capsule and the contrasted intestinal wall do not move relative to each other during filling and emptying.

Echo signs that suggest the existence of appendicointestinal fistulas:

1. in the structure of the inflammatory formation there are areas where the intestinal wall adjoins the abscess capsule without a clear boundary, and it is impossible to “separate” them on an echogram even with contrast;
2. decreased echogenicity of the tissue in the affected area;
3. the structure of the GVZPM contains gas bubbles (indirect evidence of communication with the intestine or the presence of an anaerobic pathogen, which is always accompanied by severe tissue destruction).

In some cases, the fistula tract itself is visualized - an echo-negative structure of a “twisted” shape with dense echo-positive walls emanating directly from the abscess.

Computer tomography allows us to clarify the localization of fistulas of inflammatory etiology, the stage of their formation, determine the degree of involvement of the pelvic organs in the process, as well as the depth of destructive and inflammatory changes occurring in them.

The following CT signs may indicate the risk of perforation of pelvic abscesses into the distal parts of the intestine or the formation of appendicointestinal fistulas:

• in the structure of the tubo-ovarian formation there are areas where the intestinal wall adjoins the capsule without a clear boundary;
• It is impossible to separate the border of the intestinal wall and the formation using CT; there is a sharp infiltration of cellulose in the affected area; there is an increase in the image in the intestinal wall, corresponding to the density of detritus, which indirectly indicates the destruction of the wall down to the mucous membrane.

The information content of the CT method in the diagnosis of appendicointestinal fistulas is 93.75%.

Fistulography during CT helps to increase the efficiency of genital fistula diagnostics. The introduction of a contrast agent during endoscopy (colonoscopy, cystoscopy) allows to clarify the nature of the genital fistula or fistulas (its course, length) in all patients.

Colonoscopy is indicated for patients with clinical signs of pre-perforation and perforation in the distal parts of the intestine, as well as when similar data are obtained during echography with additional contrast of the rectum or CT.

In case of a threat of perforation of the abscess into the intestinal wall, as well as in case of incomplete fistulas, the intestinal mucosa at the site of the abscess is edematous, smoothed, its vessels are dilated, and when attempting to displace it, it is slightly mobile or immobile. In case of functioning fistulas, a fistula in the form of a funnel-shaped retraction with pus escaping from it is determined on the altered mucosa.

Preliminary staining of the intestinal mucosa with methylene blue (using an enema) makes it easier to identify the altered area of the mucosa.

Differential diagnosis

Most often, purulent tubo-ovarian formations complicated by fistulas have to be differentiated from Crohn's disease and malignant neoplasms of the intestine.

Crohn's disease, or granulomatous enterocolitis, is a chronic non-specific segmental inflammatory lesion of the intestine with a predominant localization of the process in the terminal ileum. The pathological process begins in the submucosal layer of the intestine, moving successively to the muscular and serous layers. Inflammatory edema of the intestinal wall develops, granulomas are formed. The lumen of the intestine narrows, and fistulas often form, primarily with the ovaries, fallopian tube, and bladder. All this can cause secondary infection and damage to the uterine appendages.

The course of the disease is undulating. According to endoscopy data, three phases are distinguished: infiltrative, crack phase, scarring phase, or remission. One phase passes into another sluggishly, the course of the disease itself has a "smoldering" character. In some cases, the process subsides or stops altogether in one section of the intestine and occurs in the sections located distally. The sizes of the affected intestinal segments fluctuate within 6-18 cm. In the clinical picture of the disease, moderate pain in the abdomen and left hypogastric region, frequent but formed soft stools, not containing admixtures of mucus and pus even at the height of the disease, prevail. A prolonged febrile course with a rise in body temperature to 38-38.5 ° C, general weakness, pale skin, weight loss, sometimes imperative urge to defecate and disruption of all types of metabolism, especially protein, are always noted. Palpation of the abdomen is painful; sometimes a tumor-like formation is detected through the anterior abdominal wall, which is an inflammatory infiltrate or a conglomerate of thickened intestinal loops.

X-ray examination reveals narrowing of the affected section of the intestine (the "cord" symptom), thickening of the folds of the mucous membrane, and smoothing of its relief. The affected section of the intestine takes the form of a rigid tube. The relief of the mucous membrane of the cobblestone type is typical for patients with severe and prolonged Crohn's disease. The lumen of the intestine in these cases is deformed due to polypoid formations, destructive process, deep and wide cracks.

Surgical treatment for Crohn's disease is an extreme measure, it gives a high percentage of complications and fatal outcomes. In this regard, to exclude Crohn's disease, it is necessary to conduct an endoscopic examination with mandatory biopsy. For differential diagnosis, the absence of purulent contents in the material obtained during puncture of the formation is important.

Significant difficulties arise in the differential diagnosis of inflammatory diseases of the uterine appendages and sigmoid colon cancer. The incidence of sigmoid colon cancer, occurring under the guise of an inflammatory formation of the appendages, according to our data, is 0.7%. The malignant process in the sigmoid colon occurs mainly with endophytic, infiltrating growth, most often it is scirrhous cancer. By the time of differential diagnosis with a tumor-like formation of the uterine appendages, sigmoid colon cancer, as a rule, has already reached stage II, and sometimes stage III, i.e. the existing tumor is quite large.

In sigmoid colon cancer, pain may be associated with partial obstruction or dysfunction of the intestine. In the early stages, dysfunction is not associated with a mechanical obstruction, but with concomitant spastic phenomena arising from inflammation of the mesentery and caused by these pathological reflexes.

Feverish condition in sigmoid colon cancer with prolonged temperature rises to 38-39°C is most often caused by ulceration of the intestinal mucosa, decay and necrosis of tissues in this section. In malignant lesions of the sigmoid colon, pathological discharge in the form of mucus, sometimes with an admixture of pus, is quite common. A characteristic feature is the accumulation of feces with their subsequent abundant passage and the appearance of loose stools.

Upon examination, a motionless, painful tumor-like formation without clear boundaries and contours is determined in the left iliac region, the size of which can vary, but generally does not exceed 10 cm in diameter. The leading method for diagnosing sigmoid colon cancer to this day remains an X-ray examination of the intestine - irrigoscopy.

Direct radiographic signs of a malignant tumor of the sigmoid colon are a marginal or central filling defect, narrowing of the intestinal lumen, changes in the relief of the mucous membrane, and an additional shadow in the intestinal lumen. Indirect signs include intestinal spasm and the absence of haustration in a limited area, intestinal expansion above and below the affected segment, and incomplete evacuation of the contrast agent after defecation.

Rectomanoscopy and fibrocolonoscopy are of great importance in the correct diagnosis of sigmoid colon cancer. Biopsy is the final stage of the patient's examination. Of course, a positive answer indicating the presence of a malignant process is final in making a diagnosis. However, negative biopsy data, especially with infiltrative tumor growth, cannot be a sufficient basis for excluding sigmoid cancer.

Treatment

Patients with appendicointestinal fistulas are certainly recommended to undergo surgery, which, in our opinion, should always be planned, since, in addition to the traditional one, it also requires special preparation of the colon (there is always the possibility of intervention on the corresponding sections of the colon). Preparation consists of prescribing a slag-free diet and cleansing enemas (morning and evening) for 3 days.

Features of surgical intervention:

• It is optimal to perform the intestinal stage before the gynecological one. The intestinal stage is the most important one due to the high risk of developing anastomotic or suture failure in the conditions of a purulent process, and consequently, peritonitis and intestinal obstruction, therefore it is necessary to perform it especially carefully. Separation of the intestine from the abscess capsule should be performed mainly by an acute method. It is necessary to isolate the abdominal cavity with napkins beforehand, since the contents of the abscess, as a rule, flow out into the pelvic cavity. An important condition is radical excision of necrotic tissues around the fistula, however, it is impossible to remove them completely due to the spread of the infiltrate zone. In the case of incomplete appendicointestinal fistulas (intact mucosa and part of the muscular layer of the intestine), if conditions are available, the defect is closed with separate serous-muscular vicryl sutures 000 on an atraumatic needle. If this is not possible (tissue cutting), it is permissible to subsequently bring a tube for APD to the destruction zone.
• In the case where there is a complete fistula, and the infiltrate zone with abscessing does not exceed 5 cm and is located on the same wall as the fistula, without extending annularly to other walls, this part of the intestine should be resected together with the fistula. At the end of the operation, transanal intubation of the colon is performed with the tube being passed beyond the anastomosis zone.
• If the extent of the affected area is greater or it is annular, it is advisable to perform a bowel resection with anastomosis. At the end of the operation, transanal intubation of the colon is also performed with the introduction of a tube beyond the anastomosis area.
• A temporary colostomy is applied in extreme cases - in case of extensive purulent-destructive damage to the intestine (risk of developing suture failure and peritonitis), as well as in case of a serious condition of the patient.
• The intestine must be sutured according to all the rules of surgery with non-absorbable or long-absorbable synthetic suture material (thin nylon, vicryl, polysorb) in 2 layers. Catgut must not be used. The threads must be thin - No. 00 or 000, they should be applied using an atraumatic round needle:
  • 1st row - mucomuscular sutures with immersion of knots into the intestinal lumen;
  • 2nd row - serous-muscular sutures.

If conditions allow (localization of the fistula on the wall of the rectum or in the rectosigmoid region), for additional protection of the intestinal wall and prevention of peritonitis, the intestinal peritoneum above the fistula or anastomosis area is fixed to the posterior wall of the vagina.

• Revision of the genitals is necessary to determine the extent of intervention on them, with special attention to assessing the degree of involvement of the uterus and appendages on both sides in the inflammatory destructive process. The scope of the gynecological stage is selected strictly individually. In patients with fistulas, we were able to perform organ-preserving operations only in 31.8% of cases. Most patients had multiple abscesses, pronounced infiltrative changes in the parametric and pelvic tissue, the wall of the intestine bearing the fistula, involvement of the uterus in the purulent process, causing a high risk of developing severe purulent-septic complications or relapse of the disease, which required extirpation of the uterus (in this case, we always tried to preserve part of the ovary).

Appendageal vesical fistulas

When there is a risk of perforation of an abscess into the bladder, the following clinical symptoms appear in sequence in patients:

• increased frequency of urination;
• burning during urination, which later gives way to severe pain after each urination, gradually increasing; the pain becomes constant, acquiring an unbearable cutting character;
• leukocyturia and proteinuria increase, urine becomes cloudy.

The appearance of abundant purulent discharge from the urethra indicates the opening of an abscess into the bladder.

The risk of developing the described complication is very high. Its severity is determined by the nature of the microflora of the appendage abscess, the severity and duration of acute pelvic peritonitis and the intoxication associated with it, the initial functional changes in the kidneys and urinary system.

It should be emphasized that, due to the direct threat of urosepsis, delaying surgery in these cases is unacceptable, despite its technical difficulties and unfavorable initial background.

The most informative methods for diagnosing appendage-vesical fistulas are also ultrasound and computed tomography.

It should be emphasized that in order to detect an abscess of the vesicouterine space, echography (including transvaginal) should be performed with a well-filled bladder. These conditions are necessary for clear delineation of the abscess contours, detection of a defect in its anterior wall and assessment of the structural features of the posterior wall of the bladder.

Echographic signs of the threat of perforation of pelvic abscesses into the bladder:

1. There is an atypical “close” location of the abscess and the bladder (abscess of the cervical stump area, vaginal dome, or large abscess size - more than 15 cm).
2. The echogenicity of the prevesical tissue is sharply reduced; it contains cavities with thick heterogeneous contents.
3. The main symptom is the destruction of the capsule section of the formation directly adjacent to the posterior wall of the bladder, i.e. there is no clear boundary between the posterior wall of the bladder and the purulent formation. The internal contour of the bladder is deformed, the structure of its wall is heterogeneous (thickened, contains multiple echo-negative inclusions), while heterogeneous echo-positive suspension in varying quantities (accumulation of purulent exudate) can be determined in the contents of the bladder.

In some cases, the infiltrate of the prevesical tissue contains forming fistulous structures similar to those described previously.

In case of a threat of perforation of the vesicoureteral cyst into the bladder or the formation of appendage-vesical fistulas, CT signs are as follows:

• a sharp infiltration of the paravesical tissue is observed;
• there is deformation of the contours of the bladder by inflammatory infiltrate;
• the formation is tightly adjacent to the bladder and has clear contours, with the exception of the area of adjacency of the abscess and the bladder wall. The informativeness of the CT method in identifying retrovesical tissue abscesses, according to our data, was 100%.

During cystoscopy, a characteristic picture is observed: deformation of the bladder wall and bullous edema with areas of hemorrhage. Usually, perforation of the purulent formation occurs at the location of the bullous edema. As a rule, the abscess breaks through in the area of the apex of the bladder to the right or left of the midline.

Features of surgical intervention in patients with appendage-vesical fistulas:

1. When performing surgery on vesicogenital fistulas of inflammatory etiology, only transperitoneal access should be used.
2. After restoration of normal anatomical relationships of the pelvic organs, two consecutive stages of the operation are performed - gynecological and urological.
3. When vesicogenital fistulas are combined with intestinal-genital fistulas, the first stage of the operation begins with the isolation and suturing of intestinal fistulas, then adequate intervention is performed on the genitals and, last of all, on the bladder and ureter.
4. The gynecological stage of the operation consists of removing the abscess and ensuring the most adequate conditions for drainage of the pelvic cavity, including the urological areas of the operation.
5. We consider revision of the ureters on both sides to be a mandatory condition for performing the urological stage of the operation, especially in cases where significant changes in kidney function, dilation of the ureter and renal pelvis were detected before the operation.
6. The urological stage consists of the actual reconstruction of the bladder with the elimination of the fistula and restoration of normal passage of urine through the ureters. The latter intervention is performed if there are indications for it established during the operation (ureteral stricture, urinary leaks in the parametric tissue, cicatricial deformation of the ureteral orifice).
7. In the presence of incomplete vesicogenital fistulas, the altered tissues of the paravesical tissue and urinary bladder are sparingly excised, and separate vicryl or catgut sutures (No. 00) are applied to the muscle of the urinary bladder on an atraumatic needle.
8. When performing plastic surgery on incomplete vesicogenital fistulas, one should strive to be careful and try to avoid opening the bladder. If the bladder mucosa is opened during tissue excision, there is no particular danger in this situation. In such cases, the bladder is sutured in the same way as with a complete bladder fistula:
   • after additional mobilization of the bladder mucosa, it is pulled into the wound (the entire defect should be clearly visualized);
   • the bladder mucosa is sutured with separate catgut sutures (No. 00 or 000) on an atraumatic needle in the transverse direction; unlike the intestinal suture, the knots should be located outside the bladder mucosa; the distance between the sutures is 0.5-0.7 cm;
   • the second row of sutures is applied to the muscles of the bladder with catgut or vicryl No. 00, preferably in the spaces between the first row of sutures;
   • Separate sutures are applied to the tissue and peritoneum with catgut or vicryl No. 1 (third row). In cases where the gynecological stage includes extirpation of the uterus, the suture line is additionally peritonized with the vaginal wall, suturing it to the wall of the urinary bladder above the applied sutures.
9. At the end of both stages, separate peritonization of the bladder and the areas of the operation in the pelvic region is performed with mandatory isolation of the sutured fistula from the infected abdominal cavity.
10. In order to reliably prevent urinary peritonitis, the vaginal dome is left open to the abdominal cavity in all cases.
11. Mandatory stages of the operation are sanitation and drainage of the abdominal cavity and the pelvic cavity. Sanitation is performed with a 1% aqueous solution of dioxidine. In all cases, it is advisable to use an APD for drainage. Tubes are brought to the area of greatest destruction and into the lateral canals transvaginally - through an open vaginal dome or a colpotomy wound. 12. The urinary bladder is drained with a Foley catheter.

Appendageovaginal fistulas

They arise as a result of instrumental manipulations performed for the purpose of treating GPZPM (multiple punctures of pelvic abscesses, colpotomy). In the overwhelming majority of cases, they are located in the upper third of the posterior vaginal wall (at the sites of manipulations). They are mucosal defects with calcareous edges. During vaginal examination and palpation of adnexal formations, the amount of discharge from the fistula opening increases. The nature of the fistula (its length and connection with the adnexal formation) is better determined echographically when it is contrasted, for example, by inserting a metal probe into it.

Features of the operation

1. During the extirpation of the uterus, sufficient mobilization of the upper third of the vagina is performed, mainly its lateral and posterior walls, for which the cardinal ligaments are intersected in stages after separating the anterior wall of the rectum from behind, the urinary bladder and prevesical fascia from the front.
2. It is advisable to open the anterior or lateral wall of the vagina and lastly to perform resection of the upper third of the posterior wall of the vagina, which contains the fistula, already under visual control (from the inside), in order to completely excise necrotic tissue on one side and not remove excess vaginal tissue, thereby not shortening it.
3. It is advisable to perform resection of the posterior vaginal wall in a wedge-shaped manner. If the fistula is small, the posterior vaginal wall is sutured, as usual, with separate catgut sutures, capturing the uterosacral ligaments in the sutures; if the defect of the posterior wall is significant, separate sutures are first applied to the wedge-shaped excised section of the vagina, so as not to shorten it, and then the vaginal tube is sutured, as usual, with separate catgut sutures.
4. The abdominal cavity is sanitized and drained with APD tubes transvaginally.

Appendageal-abdominal fistulas

Reasons

Fistulas are formed due to two main reasons: incompletely removed purulent appendage formation, irrational or incorrect use of suture material. As a result, fistula tracts begin to form, going from the newly formed purulent cavity in place of the unremoved capsule of the purulent appendage formation to the anterior abdominal wall. Fistula tracts are usually tortuous, involve various organs in the process, forming dense infiltrates around themselves.

Symptoms

In case of a threat of abscess perforation through the anterior abdominal wall (always after previous operations), intense pains of a "twitching" nature occur in the area of the postoperative scar, infiltration and hyperemia of the latter. A small amount of purulent contents is periodically released through the formed fistula. However, even during this period, patients have fever, sometimes with chills, their general condition suffers, and the functions of the organs involved in the process are impaired.

In patients with functioning fistulas, during palpation of pelvic formations during a gynecological examination, purulent discharge from suspected fistula tracts on the anterior abdominal wall increases.

Diagnostics

Destruction of the tissues of the anterior abdominal wall is well visualized by both echoscopic and radiological examination (CT).

The information content of the CT method in diagnosing developing or formed abdominal wall-adnexal fistulas is 100%.

The following stages of development of abdominal wall fistulas are distinguished on echo- and tomograms:

1. tissue destruction up to the aponeurosis,
2. destruction of tissue down to the skin,
3. visualization of the formed fistula tract.

Fistulography helps to increase the efficiency of diagnostics. The introduction of a contrast agent into the external opening of the fistula on the anterior abdominal wall allows to determine its course and length.

Features of the operational manual

In such cases, the operation should begin with an oval dissection of the tissues around the fistula tract from the skin to the aponeurosis. After this, the resulting "tube" is covered with sterile gauze napkins and a median laparotomy is performed above the fistula tract bypassing the navel. Subsequent isolation of the fistula should be carried out in an acute way, gradually in the direction from the anterior abdominal wall deep into the small pelvis. In some cases, for better orientation, it is possible to periodically revise the fistula tract with a button probe. The choice of the volume and technique of surgical intervention on the pelvic organs are described above. We consider the need for complete sanitation of the abdominal cavity and the creation of optimal conditions for the outflow of wound discharge to be mandatory conditions for such operations. Only catgut threads should be used as suture material for these operations.

The anterior abdominal wall after excision of the purulent fistula is carefully sutured with mandatory isolation and matching of the edges of the aponeurosis along the entire length to prevent postoperative hernias. It is advisable to apply a two-row suture made of nylon or caproag (1st row separate sutures - peritoneum-aponeurosis, 2nd row - separate sutures subcutaneous tissue - skin). Subcutaneous tissue is sanitized with a 10% solution of dioxidine before suturing. Wearing a bandage is recommended in the postoperative period.