- Colitis is a condition in which the colon, the last portion of the digestive tract, is inflamed.
- Dogs and cats may experience colitis for a few days or for many months.
- Signs of colitis include diarrhea with mucus and/or fresh blood, straining to defecate, and possibly vomiting.
- There are many causes of colitis, including stress, parasites, intestinal bacterial overgrowth, altered diet, food allergies, and immune-mediated conditions.
- Diagnosis may require fecal tests, abdominal radiographs (x-rays), abdominal ultrasounds, and/or a biopsy of the intestinal tissue.
- Treatment may include antibiotics, antiparasite medications, dietary fiber supplementation, probiotics, a special diet, or immunosuppressive medications.
What Is Colitis?
Colitis is the inflammation of the colon, which is the last portion of the digestive tract. Under normal conditions, the colon stores feces while absorbing fluid and nutrients. When the colon is inflamed, these functions are affected. Additional fluid is left in the colon, resulting in diarrhea.
Colitis may be acute, occurring for only a few days, or the condition may be chronic and last for months. Any dog or cat may experience colitis.
What Are the Signs of Colitis?
Diarrhea, often with mucus and/or fresh blood, is the hallmark of colitis. Pets with colitis often defecate with greater urgency and frequency. They may strain while defecating, causing some pet owners to mistakenly believe the pet is constipated. Some pets may vomit. Despite these signs, weight loss is usually not associated with colitis.
What Causes this Condition?
Acute forms of colitis may occur during or after stressful situations, such as boarding, grooming, or thunderstorms. Colitis can also happen when pets eat table food, get into the garbage, or eat anything that isn’t part of their usual diet, including nonfood items, such as rocks and clothing.
Colitis may also be caused by intestinal parasites, such as whipworms or Giardia, or by an overgrowth of certain types of bacteria in the digestive tract.
More chronic forms of colitis are often associated with allergies to dietary proteins or with the chronic immune stimulation associated with inflammatory bowel disease.
How Is Colitis Diagnosed?
Your veterinarian will probably start with a fecal exam to check for parasites and bacterial overgrowth. A rectal exam may also be performed to detect strictures or growths that may cause straining.
If a foreign body is suspected, radiographs (x-rays) may be recommended. In some cases, an abdominal ultrasound may be recommended as well.
For more chronic cases, biopsies (tissue samples) of the colon are the best way to confirm a diagnosis. Biopsies may be obtained during abdominal surgery or with endoscopy using a fiberoptic endoscope(a long, narrow tube with a tiny camera at the tip). The endoscope can be inserted into the rectum to help your veterinarian evaluate the rectum and large intestine. The instrument includes a small forceps, which your veterinarian can guide, using the camera, to take tissue samples.
How Is Colitis Treated?
Treatment for colitis depends on the cause. Depending on the results of the fecal exam, antibiotics or antiparasite medications may be all that is needed to clear up acute cases of colitis. Probiotics (beneficial bacteria) may be added to the diet to re-establish the proper balance of microorganisms in the digestive tract.
For dogs that have eaten garbage or table food, fasting for 24 to 48 hours or feeding a bland diet may be enough to decrease or eliminate the inflammation in the digestive tract. Food should never be withheld from cats for any length of time, however, so a bland diet is a better alternative. Once the pet is feeling better, you can gradually mix in more of the regular diet.
In either case, you should always consult your veterinarian before fasting your pet or changing the diet. If a foreign body is suspected, surgery may be needed, and waiting a few days may worsen the outcome.
Many pets with colitis are treated with dietary fiber supplementation. Fiber helps to bind the additional fluid in the colon and firm up the stools.
Pets with a food allergy may require a hypoallergenic diet. Dogs and cats with immune-mediated conditions may require immunosuppressive medications.