Perianal Fistulas

Perianal Fistulas

Perianal fistulas are ulcerated tunnel-like formations in the tissues that surround the anal area of dogs1. While a variety of dogs may be affected, older German Shepherds, Setters and Retrievers are most commonly affected. The cause is unknown but affected dogs often have other skin conditions like a broad based tail or deep anal folds. Certain anatomic characteristics have been implicated in the cause2.

Symptoms of perianal fistulas
Signs may include:

  • Painful bowel movements
  • Constipation
  • Diarrhea
  • Mucus or blood in stools
  • Excessive licking and biting of the anus

Chronic pain in the affected area may make your dog restless and cry every time he is about to defecate. Some affected dogs will struggle or try to bite when their tails are lifted.

Treatment of perianal fistulas
Historically treatment was centered on surgery to remove the diseased tissues. Unfortunately the success rate is not great and there are a number of significant complications including recurrance and inability to control bowel movements.

Medical approaches, including the use of immunosuppressive drugs have proven to be effective in many cases. Stool softeners to reduce straining may help with reducing discomfort. Antibiotics and regular cleaning may also reduce inflammation.

Prognosis of perianal fistulas
Prognosis for initial healing of early lesions is good; however, recurrence is common. Dogs with moderate to severe disease frequently have relapses.

Unfortunately, perianal fistulas may require lifelong medical management with special diets and drugs that suppress the immune system. These drugs can have serious side effects and should never be combined with any other medications (including those for arthritis) unless approved by your primary care veterinarian.

Prevention of perianal fistula
Since German shepherds are at an increased risk for the disease, heredity may play some role in its development; thus, dogs with perianal fistulas should not be bred.

Questions to ask your veterinarian

  • My dog was diagnosed with perianal fistulas. How can this condition be treated?
  • My dog has some recent ulcerations around his anus and seems to be in pain when he has a bowel movement. What could be the cause?

If you have any questions or concerns, you should always visit or call your veterinarian -- they are your best resource to ensure the health and well-being of your pets.


  1. "Perianal Fistulas." American College of Veterinary Surgeons. Web.
  2. "Perianal Fistula." Merck Veterinary Manual. Web.

Perianal Fistula in Dogs… Symptoms, expectations and costs!

Perianal Fistula in dogs is about as horrible as it sounds.

Perianal Fistula in dogs…

Is a condition which affects a dog in one of the most heart wrenching ways, you see this is a term used to describe an infection of a dog’s anal glands.

Which causes the…

Affected dog to suffer from itching, inflammation and pain, particularly when they need to go “potty”. And while this condition is fairly common and treatable, even when a loving owner takes all the necessary steps to provide the proper care for their loved one, it still can affect the entire perianal region and anal area.

Which is probably due to…

The fact that this disease is often the result or “symptom” of some other “type” of disease, skin conditions or glandular issue. This is why, regardless of “why” you think your dog has developed a perianal fistula, you should always have him or her checked out by a vet.

This is also why…

We here at IndulgeYourPet also wanted to take a moment and describe exactly what a perianal fistula is so that you the owner can get a better understanding of what to look for and also have a better idea about what it will take to restore your dog’s health.

So, without further ado, let’s dive right in!

What is a perianal fistula, and what does it do?

A perianal fistula is an infection of the anal Fistulous tracts in the perianal area. Canine Perianal fistulas will be found around the dog’s anus, anal sphincter and under the tail and will present themselves as lesions that are not only weeping but also painful and itchy.

Which means that…

Your dog will want to scratch but won’t be able to, so be prepared for some butt-rubbing, scooting and perhaps even spinning in circles on their bottom in an effort to alleviate their discomfort!

Symptoms of a Perianal Fistula

Clinical signs or symptoms of this condition include lesions in the anal area that present as cuts or scratches rather than as lumps or bumps as well as physical behavior manifesting itself in behaviors designed to satiate any itching or irritation you dog may be suffering from in and around his “rear”.

After noticing…

Any of these signs or symptoms, you’re still going to want to allow your vet to do a rectal examination to be sure this is what you’re dealing with. From there, medical management must be undertaken to minimize the risk of the infection spreading, the lesions becoming otherwise infected or against an abscess forming in the glands.

In the worst-case scenario, surgery may be needed and in extreme cases, tail amputation may be necessary. However, we should state for the record that this type of treatment in only required in the most extreme cases.

Which is why…

You want to be sure and have your vet check out your dog right away if you suspect something might be wrong.

Now in less…

Extreme cases, your vet may also want to perform an anal sacculectomy if they see fit and if the condition is stopping your dog from being able to toilet. Of course, surgical treatment options for the anal sacs are only reserved for the more extreme cases.

The real concern…

Is infection. You see, when these skin tracts become infected it becomes almost impossible for the dog to perform a regular bowel movement, an issue which will clue you in as to the nature of the disease. If you see your dog straining excessively when they are going about their business then this condition may be lingering on them.

The good news is…

That if caught early, often times treating this condition can be quite simple and not require any type of surgical treatments which we will discuss later on.

Affected Breeds

Breeds known to be susceptible to Perianal Fistula include:

It is worth noting that German Shepherd Dogs are so prone to this condition that they have their very own variant, which is known as anal furunculosis.

This condition affects the tissue and perianal skin and inflames it, thus blocking the dog’s bowels. Both variations of the condition will require ongoing medical therapies and treatments should surgery not be an option.

Treatment Options

Initially your vet will want to run some blood tests and other examinations. This is just to ensure that this disease is not the result of, or connected to, any other diseases your dog may have. They will also want to ensure that the lesions are wounds, and not lumps, which might indicate the presence of cancer.

Without resorting to surgical treatments there may be other things that your vet will want to try beforehand. Topical creams are available to try and soothe the itch while preventing further spread of infection. Your vet might prescribe something like topical Tacrolimus which, though normally used for humans with severe Eczema flare ups, will solve the problem a little for your poor pooch.

Other treatments involve…

Soothing and calming the infection in order to manage it. Your vet may incorporate medical therapies to treat it, such as skin baths or steroidal creams. Cyclosporine or Ketoconazole applied to the anal sacs or anal area might also help, depending on your dog’s individual symptoms and needs. At any rate, we believe that your vet will try everything they can before resorting to amputation.

Which brings us to…

Were we like to remind folks that we here at IndulgeYourPet are not doctors, veterinarians or medical professionals. All we are is a bunch of folks who just happen to be passionate about animals and only want what’s best for them.

This is why…

If you feel like your pet may have perianal fistula (or any other health issue for that matter) the first thing that you’re going to want to do is have him or her check out by a vet ASAP!

The truth is, an early diagnosis will often lead to the “best” medical outcome for your pet regardless of what is bothering him or her, but beyond that diagnosing a medical condition early could save you a bundle in medical costs!

This is also why…

We here at IndulgeYourPet also recommend that any new pet owner take a moment and see what it might cost for you to purchase a pet insurance policy for your new animal.

Now will a pet insurance policy be right for everyone?

No, probably not. But until you fully understand what these policies “will” and “won’t” cover and how much these pet insurance policies cost, how will you know if one might be right for you?

For more information on who we feel currently offers the “best” pet insurance policies out there, we would encourage you to check out our Best Pet Insurance Policies article.

Perianal Fistulas


Condition Overview

Fistulas are draining tracts in the perianal skin caused by infection of the skin glands around the anus.


Initially they appear as draining puncture holes. Later they coalesce to form open sores and draining tracts. The discharge is foul smelling. Occasionally, fistuals connect internally with the anal sacs.


Perianal fistulas occur most often in German Shepherds, but are also found in Irish Setters, English Setters, Labrador Retrievers, and other breeds. There may be an association with breeds that have a low-slung, broad-basd tail.


The diagnosis is made by visual inspection of the perianal area.


Surgery is the most effective treatment and may include tail amputation. Cyclosporine and other immune-mediating medications may also be helpful in treating perianal fistulas. Perianal fistulas are difficult to cure and are associated with post operative complications and recurrences. Early treatment offers the best chance for recovery. Cryotherapy and laser treatments have been used with success. Unfortunately, many surgical treatments may leave the dog with a degree of fecal incontinence.


There is no prevention for this condition.


Please contact your veterinarian if you suspect your pet may have this condition.

Show Sources & Contributors +


Dog Owners Home Veterinary Handbook

Publisher: Wiley Publishing, 2007

Authors: Debra M. Eldredge, Liisa D. Carlson, Delbert G. Carlson, James M. Giffen MD

What is Perianal Fistula?

Tunnel-like formations in your dog’s skin and deeper tissues in the surrounding area of your dog’s anus are called perianal fistulas. These lesions can be minor or more serious they begin as small holes in your dog’s skin and then can become wide and deep and can ultimately surround your dog’s anus in its entirety. This condition is most likely to occur in German Shepherds, though it can happen in any breed.

Perianal fistulas can cause a great deal of pain and discomfort in your dog. Dogs that experience a perianal fistula may also have chronic diarrhea as a result of inflammatory bowel disease it is thought that these two conditions may be connected.

Perianal fistula, which is also known as anal furunculosis, occurs when a dog experiences chronic lesions around their anus that worsen, leading to deep ulcers that drain and are painful to the dog.

The cause is unknown but is suspected to involve an immune-mediated mechanism with a genetic predisposition. A broad-based tail with low tail carriage may predispose to bacterial infection and chronic inflammation of the perianal skin, but this is likely a contributing factor and not a cause of perianal fistulas. The draining tracts are lined with chronic inflammatory tissue and may extend to the lumen of the rectum and anus. Infection may spread to deeper structures involving the external anal sphincter and, therefore, should be treated promptly.

Clinical signs of perianal fistula include:

purulent discharge from the perianal region

Discomfort caused by the condition may lead to biting and licking of the perianal region. Pain may also generalized depression or change in attitude and anorexia. As the condition becomes chronic, anorectal stricture may result.

Watch the video: Anal fistula perianal fistula MRI scan protocols, positioning and planning