Colitis in Dogs

Colitis in dogs is the inflammation of the colon and can also be called large bowel diarrhea. Dogs suffering from this condition may present with increased frequency of defecation, and blood or mucous in the stools.

Colitis can be either chronic or acute in onset, and can be caused by a range of factors including parasitic infection, stress or dietary intolerances. Although relapses are common in this condition your veterinarian will be able to assist you in the most effective plan to manage this condition.

Symptoms of colitis include:

• Diarrhea or loose stools
• Blood present in the stools 
• Straining prior to or following defecation
• Vomiting 
• Increased frequency of defecation with decreased volume 

Types 
Colitis can be broken into four different forms.

Lymphocytic-plasmacytic colitis - This is characterized by the infiltration of lymphocytes and plasma cells into the mucosal lining of the small intestine resulting in inflammation; breed bias seems to be towards German Shepherds, Lundehunds, and Basenjis

Neutrophilic or ulcerative colitis - This is characterized by the infiltration of neutrophils from the circulation into the mucosal lining of the small intestine

Eosinophilic colitis - This is thought to be incited by infection, parasites or food allergies; this form of colitis appears to affect predominantly younger dogs and is characterized by the increase of eosinophils present in the mucous membrane of the gastrointestinal tract

Granulomatous colitis - This is a breed-specific inflammatory bowel disease that affects young Boxer dogs

Colitis can be caused by several factors, including:

• Breed disposition
• Parasitic infection
• Dietary intolerances or allergies
• Stress
• Bacterial infection
• Inflammatory bowel disease
  

Your veterinarian will perform a full clinical examination and ask questions to establish a complete clinical history for your dog. Your veterinarian may palpate the rectal area and inspect the feces for evidence of parasitic infection. The following diagnosis investigations can assist in confirming or excluding the diagnosis of bacterial or parasitic infection or clostridial colitis:

• Fecal smears for bacterial or parasitic infection
• Fecal flotation for parasite identification 
• Culture for bacteria 

As food sensitivities can be a common cause of chronic colitis in dogs, your veterinarian may recommend your pet is placed on a diet free of high allergen foods. If your pet’s clinical signs decrease on this diet, a diagnosis of food allergy may be made. 

If clinical signs continue or worsen on this diet, further diagnostic tests will be necessary. The following diagnostic tests may be performed:

• Hematology investigations - complete blood count and biochemical profile
• Abdominal radiographs to visualize the gastrointestinal tract 
• Ultrasonography
• Colonoscopy

Treatments for colitis can include:

Parasitic control

Deworming treatment should be given and repeated 3 weeks from first dose even if diagnostic tests show no parasitic infection

Nutrition

In order to allow your pet’s gastrointestinal system time to heal and recover food may initially be withheld for up to 2 days. Following this, the introduction of fiber may be beneficial for your pet due to it’s ability to slow luminal transit time, reducing fecal water, increasing fecal bulk and possibly reducing diarrhea. If your veterinarian suspects a food sensitivity may have caused the colitis, a novel protein diet may be introduced to your pet. This diet should only contain novel ingredients that have not previously been fed to your dog such as venison or rabbit. 

Home made diets are considered the gold standard when eliminating proteins from a pet’s diet, however, these can be time consuming and difficult to prepare. There are a range of commercially available diets your veterinarian will be able to recommend, such as novel protein diets or hydrolyzed diets.

Medication

Metronidazole may be given to your pet due to it’s ability to inhibit cell-mediated immunity. Glucocorticoids may be used therapeutically for your dog in order to suppress the immune response and inflammation.

Loperamide may be used due to it’s ability to slow excretion, decreases colonic secretion, and increase water absorption. This will be used with caution and only if infectious colitis has been ruled out. Enrofloxacin may be used for antibiotic therapy for Boxer dogs suffering from granulomatous colitis.

The prognosis is varied depending on the form of colitis your pet is suffering from. The short term prognosis for dogs who are suffering from chronic colitis is good, however, recurrent relapses are likely. Long-term novel protein diets can be beneficial for pets, although in some cases allergies may develop over time to proteins. If this occurs it may be necessary to discuss circulating different protein sources in your companion’s diet.

Unfortunately for canines that have a genetic disposition to the disease the prognosis is grave; for Boxers suffering from histiocytic colitis recovery is unlikely unless treatment is started very early in the disease. The prognosis for Basenjis suffering from immunoproliferative enteropathy and Lundehunds suffering from diarrheal syndrome is also poor.