Understand Everything About Anal Fistula

Understand Everything About Anal Fistula
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An anal fistula is a small tunnel that connects an infected gland in the rectal canal to the opening around the anus. The anus is the outer opening through which faeces are ejected from the body as excreta once the food gets digested.

There are many glands inside the anus which are responsible for producing mucus that lines the inner skin for the smooth movement of faeces. Sometimes, these glands get clogged and infected. This phenomenon leads to an abscess – a collection of pus built up within the tissues. Abscesses that are not treated on time, may develop into a fistula.

Causes/Risk Factors

The most common causes of an anal fistula include clogged glands in the anus which develop into abscesses within this structure. There might be certain medical conditions that increase the risk of
developing an anal fistula such as:

  • Trauma
  • STDs (Sexually Transmitted Diseases)
  • Cancer and radiation used for treating cancer
  • Crohn’s disease (an intestinal inflammatory disease)
  • TB (Tuberculosis)
  • Diverticulitis (a disease that occurs when tiny bulging pouches form in the large intestine and become inflamed)


An anal fistula is an unnatural condition that is an extension of the abscesses formed inside the anus. The following may be the possible symptoms of this disorder:

  • Recurring anal abscesses may develop inside the anus
  • Anal opening and the surrounding areas may have pain and swelling
  • Inflammation of the skin around the anus
  • A persistent throbbing pain while sitting, moving, or coughing
  • Bleeding
  • Passing bloody or foul-smelling pus from the fistula when you poo
  • High temperature (fever) if you have an abscess, fatigue, etc.


To diagnose this condition, your doctor may examine the area around the anus and look for any opening or fistula tract on the skin.

Then, they will try to determine the depth and direction of the fistula tunnel. In some cases, fistulas are invisible, so the following may be used to diagnose anal fistula:


It is a diagnostic procedure in which a special instrument called an anoscope is used to examine the anus and the rectum for any abnormality.

Ultrasound or MRI

When it is not possible to determine the affected areas with anoscopy, your doctor may ask you to get an ultrasound or MRI done to obtain a better view of the fistula canal developed inside the anus.

Ultrasound or sonography

Ultrasound or sonography is a type of imaging method in which high-frequency waves are used to create images of the structures within your body.


MRI stands for magnetic resonance imaging. It is a diagnostic procedure in which strong magnetic fields, magnetic field gradients, and radio waves are used to produce images of the
body organs.

Examination under anesthesia

Your doctor may examine you in the operation room to diagnose the fistula. If the fistula is confirmed, your doctor may further do some tests like
blood tests, x-ray, and colonoscopy in order to determine whether this condition is related
to Crohn’s disease or not. It has been seen that around 25% of people who suffer from
Crohn’s disease have a chance of developing anal fistulas.


is a diagnostic procedure used to detect any changes or abnormalities in the large intestine and rectum. In this procedure, a flexible, lighted tube is inserted into the colon and the areas within are then examined for any possible changes.


Since fistula involves the formation of unwanted structures within the body, it is necessary to remove them through surgery. Based on the types of anal fistulas, your doctor may resort to any of
the following treatments:


This kind of surgery is performed when the sphincter muscles (circular muscles responsible for the constriction of the anal orifice or opening) are not involved or only a little part of the muscle is involved in forming the fistula. In fistulotomy, the skin and muscle over the fistula tract are cut open which allows the fistula tract to heal.

Advanced flap procedure

Under this procedure, a flap or a piece of tissue taken from the rectum is used to cover the fistula. Complex fistulas are treated with this method. Advanced flap procedure involves the following steps:

  1. Elevating a flap or piece of tissue from the rectum to form a trap door
  2. Coring out of the infected gland and epithelised internal opening
  3. Suturing of the internal sphincter defect
  4. Closing the wound with the flap
  5. Providing appropriate drainage
  • LIFT Procedure: The ligation of the intersphincteric fistula tract (LIFT) is used to treat the anal fistulas that pass through the anal sphincter muscles. Since sphincter muscles are an extremely important part of the body, a fistulotomy may damage them. Hence, the LIFT procedure is used instead to ensure a safe treatment. During the procedure, the skin above the fistula is cut and sphincter muscles are moved apart after which the fistula is tied off.
  • Stem Cell Therapy: This treatment is suitable for complex anal fistulas caused due to Crohn’s disease. Mesenchymal stem cells are injected into the perianal fistulas to treat them because this type of cell is associated with immunomodulatory action which helps in lessening the inflammatory response, reduces the activation of CD4 T lymphocytes, and promotes the formation of regulatory T-Cells. Besides, these cells have the ability to regenerate. Thus, with this method, fistulas get treated and healed better.

If you are looking for doctors who are well-experienced and thoroughly know about anal fistula and its treatment, book appointment at Yashoda Hospital and Research Centre, Nehru Nagar, Ghaziabad, the best hospital in the whole of Delhi NCR:

Dr Ashish Gautam is a renowned and extremely experienced gastrointestinal, bariatric, and trauma surgeon, the most experienced in Delhi NCR. He has performed over 20,000 laparoscopic procedures such as lap colorectal, lap bariatric, laparoscopic common bile duct surgeries, and video-assisted thoracoscopic surgeries.

Dr Gautam has received extensive surgical training at S.N. Medical College, Maulana Azad Medical College, Lok Nayak Hospital, and Sushruta Trauma Centre. After this training, he pursued his
fellowship in minimal access and bariatric surgery.

Apart from the previously mentioned achievements, Dr Gautam is famous for his expertise in serious trauma and gunshot injury surgeries along with treating breast disease and cancer surgeries. He also has experience in thyroid and parathyroid surgery through an advanced minimal access approach.

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Yashoda Hospital

Yashoda Hospital

Yashoda Hospital is one of the best super specialty hospitals in Ghaziabad, Noida & Delhi NCR. Yashoda Hospital aims at providing the best healthcare services across the country and not just in Delhi NCR, Ghaziabad & Noida. Being a super speciality hospital, Yashoda Hospital has a number of dedicated specialities under one roof- gastroenterology, general surgery, obstetrics & gynaecology, cardiology, pulmonology & internal medicine, orthopedics, urology and many more.

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