There are several stages to treating an anal fistula:

Definitive treatment of a fistula aims to stop it recurring. Treatment depends on where the fistula lies, and which parts of the internal and external anal sphincters it crosses.

There are several options:

- Doing nothing — a drainage seton can be left in place long-term to prevent problems. This is the safest option although it does not definitively cure the fistula.

- Lay-open of fistula-in-ano — this option involves an operation to cut the fistula open. Once the fistula has been laid open it will be packed on a daily basis for a short period of time to ensure that the wound heals from the inside out. This option leaves behind a scar, and depending on the position of the fistula in relation to the sphincter muscle, can cause problems with incontinence. This option is not suitable for fistulae that cross the entire internal and external anal sphincter.

- Cutting seton — if the fistula is in a high position and it passes through a significant portion of the sphincter muscle, a cutting seton (from the Latin "seta", "bristle") may be used. This involves inserting a thin tube through the fistula tract and tying the ends together outside of the body. The seton is tightened over time, gradually cutting through the sphincter muscle and healing as it goes. This option minimizes scarring but can cause incontinence in a small number of cases, mainly of flatus. Once the fistula tract is in a low enough position it may be laid open to speed up the process, or the seton can remain in place until the fistula is completely cured. This was the traditional modality used by physicians in Ancient Egypt and formally codified by Hippocrates, who used horsehair and linen.

- Seton stitch — a length of suture material looped through the fistula which keeps it open and allows pus to drain out. In this situation, the seton is referred to as a draining seton. The stitch is placed close to the ano-rectal ring – which encourages healing and makes further surgery easy.

- Fistulotomy — till anorectal ring

- Colostomy — to allow healing

- Fibrin glue injection is a method explored in recent years, with variable success. It involves injecting the fistula with a biodegradable glue which should, in theory, close the fistula from the inside out, and let it heal naturally. This method is perhaps best tried before all others since, if successful, it avoids the risk of incontinence, and creates minimal stress for the patient.

- Fistula plug involves plugging the fistula with a device made from small intestinal submucosa. The fistula plug is positioned from the inside of the anus with suture. According to some sources, the success rate with this method is as high as 80%. As opposed to the staged operations, which may require multiple hospitalizations, the fistula plug procedure requires hospitalization for only about 24 hours. Currently, there are two different anal fistula plugs cleared by the FDA for treating ano-rectal fistulae in the United States. This treatment option does not carry any risk of bowel incontinence. In the systematic review published by Dr Pankaj Garg, the success rate of the fistula plug is 65-75%.

- Endorectal advancement flap is a procedure in which the internal opening of the fistula is identified and a flap of mucosal tissue is cut around the opening. The flap is lifted to expose the fistula, which is then cleaned and the internal opening is sewn shut. After cutting the end of the flap on which the internal opening was, the flap is pulled down over the sewn internal opening and sutured in place. The external opening is cleaned and sutured. Success rates are variable and high recurrence rates are directly related to previous attempts to correct the fistula.

- LIFT Technique is a novel modified approach through the intersphincteric plane for the treatment of fistula-in-ano, known as LIFT (ligation of intersphincteric fistula tract) procedure. LIFT procedure is based on secure closure of the internal opening and removal of infected cryptoglandular tissue through the intersphincteric approach. Essential steps of the procedure include, incision at the intersphincteric groove, identification of the intersphincteric tract, ligation of intersphincteric tract close to the internal opening and removal of intersphincteric tract, scraping out all granulation tissue in the rest of the fistulous tract, and suturing of the defect at the external sphincter muscle. The procedure was developed by Thai colorectal surgeon, Arun Rojanasakul, The first reports of preliminary healing result from the procedure were 94% in 2007. Additional ligation of the intersphincteric fistula tract did not improve the outcome after endorectal advancement flap.

- Fistula clip closure (OTSC Proctology) is the latest surgical development, which involves the closure of the internal fistula opening with a superelastic clip made of nitinol (OTSC). During surgery, the fistula tract is debrided with a special fistula brush and the clip is transanally applied with the aid of a preloaded clip applicator. The surgical principle of this technique relies on the dynamic compression and permanent closure of the internal fistula opening by the superelastic clip. Consequently, the fistula tract dries out and heals instead of being kept open by continuous feeding with stool and fecal organisms. This minimally-invasive sphincter-preserving technique has been developed and clinically implemented by the German surgeon Ruediger Prosst. First clinical data of the clip closure technique demonstrate a success rate of 90% for previously untreated fistulae and a success rate of 70% for recurrent fistulae.

- PERFACT Procedure is another latest addition to the armamentarium to treat complex and highly complex fistula-in-ano. It is a minimally cutting procedure as both the anal sphincters (internal and external sphincters) are not cut/damaged at all. Therefore, the risk of incontinence is minimal. PERFACT procedure (proximal superficial cauterization, emptying regularly fistula tracts and curettage of tracts) entails two steps: superficial cauterization of mucosa at and around the internal opening and keeping all the tracts clean. The principle is to permanently close the internal opening by granulation tissue. This is achieved by superficial electrocauterization at and around the internal opening and subsequently allowing the wound to heal by secondary intention. Early results of this procedure are quite encouraging for complex fistula-in-ano (86.4% in highly complex anal fistulae). The procedure is effective even in fistula associated with abscess, supralevator fistula-in-ano and fistula where the internal opening is non-localizable.

Treatment for fistula varies depending on the cause and extent of the fistula, but often involves surgical intervention combined with antibiotic therapy.

Typically the first step in treating a fistula is an examination by a doctor to determine the extent and "path" that the fistula takes through the tissue.

In some cases the fistula is temporarily covered, for example a fistula caused by cleft palate is often treated with a palatal obturator to delay the need for surgery to a more appropriate age.

Surgery is often required to assure adequate drainage of the fistula (so that pus may escape without forming an abscess). Various surgical procedures are commonly used, most commonly fistulotomy, placement of a seton (a cord that is passed through the path of the fistula to keep it open for draining), or an endorectal flap procedure (where healthy tissue is pulled over the internal side of the fistula to keep feces or other material from reinfecting the channel). Treatment involves filling the fistula with fibrin glue; also plugging it with plugs made of porcine small intestine submucosa have also been explored in recent years, with variable success. Surgery for anorectal fistulae is not without side effects, including recurrence, reinfection, and incontinence. High rate of recurrence and more chances of complications like incontinence are always there in fistula surgeries (Anal Fistula).

It is important to note that surgical treatment of a fistula without diagnosis or management of the underlying condition, if any, is not recommended. For example, surgical treatment of fistulae in Crohn's disease can be effective, but if the Crohn's disease itself is not treated, the rate of recurrence of fistula is very high (well above 50%).

Some people will have an active infection when they present with a fistula, and this requires clearing up before definitive treatment can be decided.

Antibiotics can be used as with other infections, but the best way of healing infection is to prevent the buildup of pus in the fistula, which leads to abscess formation. This can be done with a seton.

Courses of treatment typically include the following:

- Draining the pus once awhile as it can build up a strong odor

- Antibiotics when infection occurs.

- Surgical excision is indicated with recurrent fistular infections, preferably after significant healing of the infection. In case of a persistent infection, infection drainage is performed during the excision operation. The operation is generally performed by an appropriately trained specialist surgeon e.g. an otolaryngologist or a specialist General Surgeon.

- The fistula can be excised as a cosmetic operation even though no infection appeared. The procedure is considered an elective operation in the absence of any associated complications.

The primary aim of treatment of a newly formed oroantral communication is to prevent the development of an oroantral fistula as well as chronic sinusitis. The decision on how to treat OAC/OAF depends on various factors. Small size communications between 1 and 2 mm in diameter, if uninfected, are likely to form a clot and heal by itself later. Communications larger than this require treatments to close the defect and these interventions can be categorised into 3 types: surgical, non-surgical and pharmacological.

Medications may be needed as an adjunct to assist the closure of the defect. Antibiotics can help control or prevent any sinus infections. Preoperative nasal decongestants usage can reduce any existing sinus inflammation which will aid surgical manipulation of the mucosa over the bone.

In people with renal failure, requiring dialysis, a cimino fistula is often deliberately created in the arm by means of a short day surgery in order to permit easier withdrawal of blood for hemodialysis.

As a radical treatment for portal hypertension, surgical creation of a portacaval fistula produces an anastomosis between the hepatic portal vein and the inferior vena cava across the omental foramen (of Winslow). This spares the portal venous system from high pressure which can cause esophageal varices, caput medusae, and hemorrhoids.

Vesicovaginal fistulae are typically repaired either transvaginally or laparoscopically, although patients who have had multiple transvaginal procedures sometimes attempt a final repair through a large abdominal incision, or laparotomy.

The laparoscopic (minimally invasive) approach to VVF repair has become more prevalent due to its greater visualization, higher success rate, and lower rate of complications.

It is surgically corrected, with resection of any fistula and anastomosis of any discontinuous segments.

After diagnosing rectovaginal fistula, it is best to wait for around 3 months to allow the inflammation to subside. For low fistulae, a vaginal approach is best, while an abdominal repair would be necessary for a high fistula at the posterior fornix.

A circular incision is made around the fistula and vagina is separated from the underlying rectum with a sharp circumferential dissection. The entire fistulous tract, along with a small rim of rectal mucosa is incised. The rectal wall is then closed extramucosally.

Most rectovaginal fistuals will need surgery to fix. Medications such as antibiotics and Infliximab might be prescribed to help close the rectovaginal fistula or prepare for surgery.

Rectovestibular fistula is the most common defect of the rectum and anal canal in females.

Neonates with TEF or esophageal atresia are unable to feed properly. Once diagnosed, prompt surgery is required to allow the food intake. Some children do experience problems following TEF surgery; they can develop dysphagia and thoracic problems. Children with TEF can also be born with other abnormalities, most commonly those described in VACTERL association - a group of anomalies which often occur together, including heart, kidney and limb deformities. 6% of babies with TEF also have a laryngeal cleft.

Rectovaginal fistulas are often the result of trauma during childbirth (in which case it is known as obstetric fistula) where improper medical interventions are used, such as episiotomy with forceps/vacuum extraction or in situations where there is inadequate health care, such as in some developing countries. Rectovaginal fistula is said to be known as the leading cause in maternal death in developing countries. Risk factors include prolonged labour, difficult instrumental delivery and paramedian episiotomy. Rates in Eritrea are estimated as high as 350 per 100,000 vaginal births. Fistulas can also develop as a result of physical trauma to either the vagina or anus, including from rape. Women with rectovaginal fistulae are often stigmatized in developing countries, and become outcasts.

Rectovaginal fistula can also be a symptom of various diseases, including infection by lymphogranuloma venereum, or the unintended result of surgery, such as episiotomy or sexual reassignment surgery. They may present as a complication of vaginal surgery, including vaginal hysterectomy. They are a recognized presentation of rectal carcinoma or rarely diverticular disease of the bowel or Crohn's disease. They are seen rarely after radiotherapy treatment for cervical cancer.

Although generally benign, the cyst must be removed if the patient exhibits difficulty in breathing or swallowing, or if the cyst is infected. Even if these symptoms are not present, the cyst may be removed to eliminate the chance of infection or development of a carcinoma, or for cosmetic reasons if there is unsightly protrusion from the neck.

Thyroid scans and thyroid function studies are ordered preoperatively; this is important to demonstrate that normally functioning thyroid tissue is in its usual area.

Surgical management options include the Sistrunk procedure, en bloc central neck dissection, suture-guided transhyoid pharyngotomy, and Koempel's supra-hyoid technique. Cystectomy is an inadequate approach.

Colostomy is recommended by most surgeons, and has a good prognosis, with 90% of patients regaining normal bowel control. Since the rectal opening and anal orifice in a vestibular fistula tend to be short and narrow, a colostomy is usually performed to allow decompression of the bowel unless the orifice is wide enough to allow normal defecation. Colostomy is often followed by posterior sagittal anorectoplasty (PSARP), a surgical procedure to repair the anal orifice, at a later date. Some surgeons prefer to perform an immediate PSARP without a colostomy first, while others perform neither a colostomy nor a PSARP and instead opt for a simple dilatation of the orifice to allow stool to pass and the bowel to decompress. It has been suggested that only experienced surgeons should perform repair without an initial colostomy.

It is often caused by childbirth (in which case it is known as an obstetric fistula), when a prolonged labor presses the unborn child tightly against the pelvis, cutting off blood flow to the vesicovaginal wall. The affected tissue may necrotize (die), leaving a hole.

Vaginal fistulas can also result from particularly violent cases of rape, especially those involving multiple rapists and/or foreign objects. Some health centers in countries such as the Democratic Republic of Congo have begun to specialize in the surgical repair of vaginal fistulas.

It can also be associated with hysterectomy, cancer operations, radiation therapy and cone biopsy.

A salivary gland fistula (plural "fistulae") is a fistula (i.e. an abnormal, epithelial-lined tract) involving a salivary gland or duct.

Salivary gland fistulae are almost always related to the parotid gland or duct, although the submandibular gland is rarely the origin.

The fistula can communicate with the mouth (usually causing no symptoms), the paranasal sinuses (giving rhinorrhea) or the facial skin (causing saliva to drain onto the skin).

The usual cause is trauma, however salivary fistula can occur as a complication of surgery, or if the duct becomes obstructed with a calculus.

Most parotid fistulae heal by themselves within a few weeks.

Many women delay treatment for decades. Surgeons often will correct the fistula through major gynecological surgery. Newer treatments can include the placement of a stent and is usually successful. In 0.5-2.5% of major pelvic surgeries a ureterovaginal fistula will form, usually weeks later. If the fistula cannot be repaired, the clinician may create a permanent diversion of urine or urostomy. Risks associated with the repair of the fistula are also associated with most other surgical procedures and include the risk of adhesions, disorders of wound healing, infection, ileus, and immobilization. There is a recurrence rate of 5%–15% in the surgical operation done to correct the fistula.

Patients with enteric content exiting a wound on their abdomen are motivated to undergo operation. The majority will close spontaneously within approximately 6 weeks. If it has not closed by 12 weeks, it is unlikely to do so and definitive surgery should be planned. The median time to definitive repair from fistula onset was 6 months (range 1 day to 28 months). The 6-month time course is commonly utilized by groups with significant experience treating fistulas, owing to the trend in encountering a less hostile abdomen than in the early phases. Some evidence also suggests that somatostatin can be an effective treatment with respect to reducing closure time and improving the spontaneous closure rate of enterocutaneous fistulas.

A method for repairing long-gap esophageal atresia using magnets has been developed, that does not require replacing the missing section with grafts of the intestine or other body parts. Using electromagnetic force to attract the upper and lower ends of the esophagus together was first tried in the 1970s by using steel pellets attracted to each other by applying external electromagnets to the patient. In the 2000s a further refinement was developed by Mario Zaritzky's group and others. The newer method uses permanent magnets and a balloon.

1. The magnets are inserted into the upper pouch via the baby's mouth or nose, and the lower via the gastrotomy feeding tube hole (which would have had to be made anyway to feed the baby, therefore not requiring any additional surgery).

2. The distance between the magnets is controlled by a balloon in the upper pouch, between the end of the pouch and the magnet. This also controls the force between the magnets so it is not strong enough to cause damage.

3. After the ends of the esophagus have stretched enough to touch, the upper magnet is replaced by one without a balloon and the stronger magnetic attraction causes the ends to fuse (anastomosis).

In April 2015 Annalise Dapo became the first patient in the United States to have their esophageal atresia corrected using magnets.

The Sistrunk procedure is the surgical resection of the central portion of the hyoid bone along with a wide core of tissue from the midline area between the hyoid and foramen cecum. It involves excision not only of the cyst but also of the path's tract and branches, and removal of the central portion of the hyoid bone is indicated to ensure complete removal of the tract. The original Sistrunk papers (the "classic" procedure described in 1920, and the "modified" procedure described in 1928) are available on-line with a modern commentary.

In general, the procedure consists of three steps:

1. incision

2. resection of cyst and hyoid bone

3. drainage and closure

There are several versions of the Sistrunk procedure, including:

- "classic": excision of the center of the hyoid bone along with a thyroglossal duct cyst, removal of one-eighth inch diameter core of tongue muscle superior to the hyoid at a 45 degree angle up to the foramen cecum to include mucosa, removal of one-quarter inch of the center of the hyoid bone, closure of the cut ends of the hyoid bone, and placement of a drain.

- modified: dissection through the tongue base but not through the mucosa. The modified Sistrunk procedure is the procedure of choice in both primary and revision cases.

- hyoid cartilage division: In cases without mature ossification of the hyoid bone, the non-fused cartilage portion can be divided by monopolar Bovie electro-cauterization or scissors. There were no statistical differences between this modified Sistrunk and the conventional Sistrunk procedure.

The procedure is relatively safe. In a study of 35 pediatric patients, Maddalozzo et. al found no major complications, but did observe minor complications (6 patients presented with seroma and 4 patients with local wound infections). A more recent paper analyzed 24 research studies on different treatment complications of thyroglossal cyst, and reported a total minor complications rate of 6% for the Sistrunk operation (classical or modified) and simple cystectomy treatment modalities. The Sistrunk procedure also showed better outcomes concerning the rate of overall recurrence, i.e. has the lowest rate of recurrence.

Sistrunk procedure results in a 95% cure rate and 95–100% long-term survival.

Treatments range from recommendations for over-the-counter products to more invasive surgical procedures.

Among the most common outpatient advice given to patients with less severe disorders include a high-fiber diet, application of ointment, and increased water intake. More serious procedures include the removal of affected tissue, injection of botulinum toxin, or surgically opening the fistula tract in the sphincter muscle.

Birth injuries that result in the formation of fistulas and urinary and fecal incontinence have been found to be strongly associated with economic and cultural factors. Teenagers and women who sustain injuries that develop into ureterovaginal fistulas during childbirth suffer significant social stigma. Ureterovaginal fistulas related to prolonged, obstructed labor are rare in developed nations but are more common in countries where access to emergent obstetrical care is limited.

With a high lesion, many children have problems controlling bowel function and most also become constipated. With a low lesion, children generally have good bowel control, but they may still become constipated.

For children who have a poor outcome for continence and constipation from the initial surgery, further surgery to better establish the angle between the anus and the rectum may improve continence and, for those with a large rectum, surgery to remove that dilated segment may significantly improve the bowel control for the patient. An antegrade enema mechanism can be established by joining the appendix to the skin (Malone stoma); however, establishing more normal anatomy is the priority.

Low-output fistula: < 200 mL/day

Moderate-output fistula: 200-500 mL/day

High-output fistula: > 500 mL/day