Rectal and Anorectal Narrowing (Strictures)
Rectal and anorectal strictures are narrowings which are caused by scar tissue. They are more often seen in Beagles, German Shepherds and poodles than in other breeds of dog. They are not common but tend to involve the rectum and the anus. The scar tissue result from inflammation, injury from foreign objects, or trauma such as bite wounds.
The symptoms of rectal tumors include blood in the fecal matter, diarrhea, straining to defecate and pain when defecating. Treatment usually includes surgery but it may not be effective as the disease can spread before any symptoms become noticeable.
Rectal polyps are growths which are not commonly seen. They are usually benign. They do not spread to other tissues. Larger polyps may be malignant. The symptoms include blood in the fecal matter, diarrhea and straining when defecating. The polyp can be felt during a rectal examination and the surface can bleed easily. The polyp may protrude from the anus. Polyps can be removed via surgery. The recovery tends to be quick and the prognosis is usually good. It is possible for new polyps to develop after surgery. A tissue sample of the polyp may be analyzed to confirm the diagnosis.
Rectal prolapse is a condition where on or more rectal layers can protrude through the anus. It can be incomplete prolapse which means that only the innermost layer protrudes or a complete prolapse in which all the layer protrude. It is commonly seen in young dogs who have had severe diarrhea or who strain to defecate routinely. It can be caused by several intestinal, urinary or anorectal diseases. It can also be caused by perineal hernias, or other conditions affecting the anal sphincter nerves.
There may be a long, cylinder shaped mass visibly protruding through the anus. Other parts of the intestine can have a similar appearance to this when they prolapse, but any prolapse should be quickly examined by a veterinarian.
The veterinarian will need to identify the prolapse and the cause. Incomplete or small prolapses may be manually replaced under anesthetic. The anus may then be partially closed with stitches for five to seven days which can help prevent a recurrence. Topical anesthetic or an epidural may be administered to prevent straining. In some cases, it may necessary to repair the prolapse through surgery. After this, the dog may be given a stool softener and a moist diet. If the animal has diarrhea following the procedure, the veterinarian should be contacted and additional treatment may be necessary.
Swallowing a sharp object such as a needle or sharp bone may cause a tear in the rectum or anus. Rectal and anal tears can also be caused by injury. The tear may be on the surface rectal layers which is described as a partial tear, or it may penetrate all the rectal layers which is described as a complete tear. The symptoms can include rectal bleeding, reluctance to defecate, straining to defecate and constipation. Rectal tears are diagnosed based on the symptoms and a rectal and anal examination. There may be swelling if the injury occurred some time before the examination. The wound will be thoroughly cleaned and stitched. Depending on the location of the tear, it may be accessible through the anus. If not, the dog will require abdominal surgery to stitch the tear. The veterinarian will prescribe antibiotics and stool softeners.