Rectal Stricture in Dogs
Rectal stricture is a condition where the rectal or anal opening is constricted due to the presence of scar tissue from inflammation, a previous injury, or an aggressive cancer growth. This narrow opening(s) obstructs the passage of stools, thereby resulting in issues with the cat's digestive system. Rectal stricture is not hereditary.
Dogs and cats of both genders, and most breeds and ages may be affected by strictures. If you would like to learn more about how this condition affects cats, please visit this page in the PetMD health library.
Symptoms and Types
Symptoms will vary depending on the severity of the condition. Some symptoms include constipation, diarrhea, and difficulties while defecating. The feces is often covered in mucus and blood-stained. There also may be a compensatory increase in the size of the dog's large intestine as a result of the stricture.
Both male and female dogs suffer from strictures, as do most breeds and age groups. Although, dogs that have had rectal or anal abscesses, inflammation, fistulas, a foreign body in the anal passage, or fungal infection are at a higher risk of sustaining the condition. Cuts or wounds in the area, cancerous growths, and some surgeries (e.g., removal of part of the rectum for biopsy) can also put animals at higher risk for developing strictures.
Your veterinarian will perform a thorough physical exam on your dog, taking into account the history of its symptoms and possible incidents that might have precipitated the stricture. Some common tests include a complete blood count and a urinalysis, which will usually return as normal. If your dog has an existing infection or inflammation, the white blood count may be high.
A manual examination of the rectum might be required to determine the extent and location of the stricture. Ultrasonography of the abdominal area may also be performed; this might show thickening of the stomach walls and a change in the structure of the internal tissues, especially if cancer is present.
X-rays of the abdominal area and injection of contrast dyes (barium, air, or double-contrast enema) may show narrowing of the rectal and intestinal canal. These tests will be completed as a multi-step process: first, a warm water enema will be administered, followed by the dye injection six hours later. A combination of air and barium media is most effective for testing.
A colonoscopy, using a tubular, flexible camera inserted through the anal opening, will help your veterinarian to visualize the stricture internally and determine the extent of the stricture. This is also a convenient method for obtaining a tissue sample for further evaluation, which is helpful for determining if you dog has cancer, or a fungal or parasitic infection.
Once your veterinarian has differentiated between other conditions and strictures, treatment will involve relieving the dog's pain and encouraging elmination of any waste still remaining in its intestines; this is done by using stool softeners, enemas, or drugs. Dogs should be given plenty of fluids prior to the administration of the enema; some dogs require anesthesia prior to the procedure.
Corticosteroids may also be given to regulate inflammation, but not before your dog is fully examined for the presence of an infection, since corticisteroids can have an adverse effect if infection is present.
The underlying cause of the stricture will then be treated in order to widen the cat's narrowed canal. If an infection is found, your veterinarian will prescribe medications -- either antifungals or antibiotics -- to eliminate the specific infection your dog has.
Surgery may be advisable for widening the narrowed opening. This can be done by using a balloon-like device to open the canal, or for milder strictures, a temporary stent may be used. For more extensive lesions, partial or complete removal of the canal may be required. Antimicrobial drug therapy may be prescribed to prevent infections during and after surgery.
If a cancerous tumor is found to be present, radiotherapy and chemotherapy may be called for.
Living and Management
Be attentive to any recurring symptoms or signs in your dog. If the original cause of the stricture was cancer, symptoms of metastasis will be of concern. Some complications of medical management include ineffective treatment, diarrhea, dehydration, and adverse effects of medications.
If the veterinarian chose a balloon dilation procedure for the dog's treatment, be aware deep rectal tears, hemorrhaging, or full-thickness tearing of the intestinal walls may occur. However, dogs with smaller strictures are usually treated easily and managed with balloon dilation.
Surgery may also result in fecal incontinence, secondary stricture formation, and opening of the wound site. Dogs requiring surgery will usually have limited prognosis due to frequent complications.