Rectal Prolapse in Dogs

Rectal prolapse occurs in a wide range of species and may be caused by chronic diarrhea, enteritis, intestinal parasites, rectal disorders and other underlying conditions. Diagnosis can be made based on the clinical signs (ie, a cylindrical mucosal mass protruding from the anus). Treatment includes lavage of the protruding tissue, reduction, and placement of a temporary purse-string suture. Local anesthesia may help reduce straining and aid in prolapse reduction, especially in large animals.

In rectal prolapse, one or more layers of the rectum protrude through the anus due to persistent tenesmus (straining to defecate) associated with intestinal, anorectal, or urogenital disease. Prolapse may be classified as incomplete, in which only the rectal mucosa is everted, or complete, in which all rectal layers are protruded.

Etiology

Rectal prolapse is common in young animals in association with severe diarrhea and tenesmus that results from severe enteritis (e.g. inflammation from inflammatory bowel disease), endoparasitism (round worms), disorders of the rectum (eg, foreign bodies, lacerations, diverticula, or sacculation), neoplasia (cancer) of the rectum or distal colon urolithiasis urethral obstruction cystitis dystocia colitis prostatic disease Perineal hernia or other interruption of normal innervation of the external anal sphincter may also lead to rectal prolapse. Animals of any age, breed, or sex may be affected.

Clinical Findings and Diagnosis

Diagnosis is based on the primary clinical sign, a cylindrical tissue mass protruding from the anus. Other common signs include ulceration, inflammation, and congestion of the rectal mucosa. Shortly after the onset of a prolapse there is a short, non-ulcerated, inflamed segment of rectal tissue; later, the mucosal surface darkens, hardens, and may become necrotic.

Treatment

The main goal of treatment is to restore the protruding rectal and anal tissue to its normal position. This will reduce damage or the risk of tissue death. General anesthesia is often required to replace the prolapsed tissue. Once the prolapse has been reduced and is back in place, a purse-string suture may be placed around the anal opening for 5-7 days to prevent a recurrence of the prolapse. A purse-string suture is a special type of stitch that will help preserve the anal opening and reduce the risk of the prolapse recurring.

Severe Rectal Prolapse

In cases of severe prolapse, dead or dying rectal tissue may need to be surgically removed. Resection (cutting out the tissue) and anastomosis (reconnecting the ends of the rectum where the dead tissue was cut away) may be required. Surgery is designed to remove dead tissue, reduce the risk of further damage to the tissue, and reduce the risk of a serious inflammatory reaction called sepsis.

Treating Underlying Causes

Some underlying causes of rectal prolapse in dogs will also need to be addressed at the same time as the prolapse:

• Bowel obstruction: If the prolapse has occurred because of a foreign body obstruction in the bowel, it should be addressed at the same time as the prolapse. This will avoid additional tissue damage to other sections of the bowel.

• Urethral obstruction: Urethral obstructions should also be addressed while your dog is anesthetized, to avoid continued straining and prevent damage or rupture to the urinary bladder and urethra.

• Dystocia (difficult birth): Pregnant females with a puppy they cannot push out will also require surgical intervention to safely remove the puppy via cesarean section. Prolonged straining with dystocia (difficult birth) can lead to maternal exhaustion, potential rupture of the uterus, and possible death of the puppy.

• Enlarged prostate: Intact (not neutered) male dogs who suffer from rectal prolapse should be evaluated for an enlarged prostate, which can cause straining as the prostate partially obstructs the flow of urine through the urethra.

Recovery and Management of Rectal and Anal Prolapse in Dogs

After the prolapse has been resolved, additional treatment should address the underlying cause(s) of the prolapse. If your dog is intact and suffers from an enlarged prostate, they may benefit from castration (neutering), which will result in a gradual decline in male hormone levels, leading to a decrease in the size of the prostate gland. If a fecal examination is positive for parasites, your dog should be dewormed and placed on a monthly oral or topical heartworm and intestinal parasite prevention to reduce the likelihood of reinfection. Stool softeners and a low-residue diet may also be recommended in the post-surgical period so your dog can pass bowel movements more easily.

In cases of recurrent rectal prolapse, long-term management of the condition may require that your dog undergoes a colopexy. This is a type of surgery in which the vet attaches your dog’s colon to the left side of the abdominal wall so it cannot come out of the anus.

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