Colitis in Dogs
What is colitis?
Colitis simply refers to
inflammation of the large intestine or colon. Colitis is most commonly
used to describe diarrhea or loose stools associated with the large bowel. Large
bowel diarrhea is also used synonymously with colitis.
What are the clinical signs of colitis?
Most dog owners report seeing frequent, small volumes of semi-formed to liquid feces. Many dogs will exhibit straining during and after defecation, and small amounts of bright red blood will often be passed near the end of defecation. Mucus or fat is seen in many cases of chronic colitis. Vomiting occurs in less than a third of the cases of colitis or large bowel diarrhea. Weight loss is rare.
What causes colitis?
The causes of colitis include stress, infections (including Salmonella, Clostridium, and E. coli), and parasites (including, Giardia, Cryptosporidium and whipworms), trauma, allergic colitis and primary inflammatory bowel disease (lymphoplasmacytic, eosinophilic, granulomatous and histiocytic types). Colitis may also occur after ingesting contaminated food, being in contact with infected dogs or after chronic exposure to a wet environment.
"Inflammation in the colon results in reduced water absorption and decreased ability to store feces in the colon."
Whatever the cause, the inflammation in the colon results in reduced water absorption and decreased ability to store feces in the colon. This causes the classic symptom of frequent small amounts of diarrhea, often with mucus or blood.
How is colitis diagnosed?
The diagnosis of
colitis is based on your pet's clinical signs and history, microscopic
evaluation of the feces, rectal examination, cytology and blood tests.
Additional testing such as radiographs to examine the colon and intestinal
tract, colonoscopy and colon biopsies, fecal cultures, barium enemas or
ultrasound evaluation of the abdomen may be necessary. These tests are
important to rule out conditions such as colonic tumors or polyps, irritable
bowel syndrome, cecal inversion and ileocecocolic intussusception (a condition
in which the intestines 'telescope' or fold into themselves).
How is colitis treated?
The specific cause of colitis will dictate the appropriate treatment. Non-specific treatment includes fasting for 24-48 hours, feeding a low residue or hypoallergenic diet, increasing dietary fiber content, and adding fermentable fiber such as psyllium, beet pulp or fructooligosaccharides (FOS) to the food. Antimicrobial drugs may be indicated, depending on your dog's diagnosis. Anti-inflammatory or immunosuppressive drugs may be used in cases of inflammatory or immune-mediated colitis. Drugs that modify the colon's motility may provide symptomatic relief.
What is the prognosis if my dog has colitis?
"For most dogs diagnosed with colitis, the prognosis is excellent for a speedy recovery."
For most dogs diagnosed with colitis, the prognosis is excellent for a speedy recovery. Stress colitis is one of the leading causes of colitis in dogs and with a simple change in diet and medication to resolve the inflammation or infection in the colon most dogs are back to normal within three to five days. Chronic, severe or recurrent cases should have further diagnostic tests performed to determine the exact cause and proper treatment. For many dogs with chronic colitis, strict dietary control and judiciously used medications keep the condition under control.