Inflammatory Bowel Disease

Inflammatory Bowel Disorder (IBD) is a chronic problem, and its primary symptom is recurring diarrhea that may be accompanied by some vomiting.

Indefinite Beginnings

Richard Goldstein, DVM, an internal medicine specialist at the Cornell University Hospital for Animals, speculates there are various causes for the disorder, not one, and that IBD may represent a collection of differing digestive disorders since it is idiopathic, meaning from unknown causes.

Goldstein, who is board certified by the College of Veterinary Internal Medicine, describes the disorder as an inflammatory process of the intestines, involving immune system cells. These cells are sent to intestinal walls in their role of fending off invasions by antigens (foreign substances evoking an immune response), although what these antigens are, what fosters them, or if any are actually present is usually unknown.

Still, the disorder exhibits characteristic signs even if the conditions causing them are not yet understood. Dogs are often uncomfortable when eating because the stomach empties slowly into the intestines, leaving them feeling prematurely full. Severity of this disorder covers a wide range. When the inflammation centers on the small bowel (intestine), the signs are usually more sever and include poor appetite and weight loss.

When IBD is located in the large bowel, frequent diarrhea, which sometimes contains blood or mucous, can occur and ranges from periodic soft stools to constant, liquidy diarrhea. Dogs with IBD in the large bowel usually retain good appetites and appear otherwise normal. More severely affected dogs are at significant risk of anorexia (loss of appetite), and the diarrhea quickly can become trying to dog and human alike.

Scoping Out the Source

To diagnose inflammatory bowel disorder, one must see signs for at least a few weeks.

Diagnosis starts with testing for other sources of intestinal inflammation. Blood tests and fecal exams are performed. At this point, a temporary switch to a new diet may be prescribed since it is the most common treatment to rule out a food allergy. When other disorders are ruled out, a biopsy is conducted, and an endoscope is used to take a surface sample of intestinal tissue for examination.

Although rarely called for, a surgical biopsy may be chosen instead of endoscopy for a fuller tissue sample, a procedure dogs handle considerable better than do most humans, notes Goldstein. A pathologist examines the tissue sample, looking for excessive numbers of inflammatory cells from the immune system. The pathologist then identifies the prevalence and type of such cells. This helps determine the treatment.

The most typical immune system cells triggering inflammatory bowel disease are lymphocytes and plasma cells. These are normally present in intestinal tissues, with high numbers associated with inflammation. If eosinophils are the most prevalent cells, the inflammation is more likely due to an allergic response. Least commonly found are neutrophils that may arise in response to bacterial infection.

If an early diagnosis is not made, a dog's tolerance to invading antigens and his capacity to digest nutrients may become compromised, and the dog's health will deteriorate. As a dog begins to lose weight and resistance fades, other diseases can take hold in the weakened pooch and complicate recovery. Early diagnosis is therefore important, and quickly moving toward biopsy is wise.

Prognosis is Good

Treatment focuses on three tracks.

The first is the most widely useful and involves decreasing exposure to those antigens that are believed to be causing the immune system to react. One possible culprit is the dog's diet, in particular the protein source. Accordingly, a diet is chosen using a protein the dog is unlikely to have ever consumed, such as fish, duck, venison, even Kangaroo, all of which are available in commercial preparations. Some dogs will require a diet composed of component (hydrolyzed) peptides. The new diet may be given for several months or for the lifespan of the dog.

The second option involves treatment with medication. Often, antibiotics will be used to bring the overall gastrointestinal-tract bacterial load back to normal.

If the above options don't work, an immunosuppressive drug, such as a steroid, may be given to lower inflammation. Medications may only be used for weeks or months. While the treatments may sound complex, they can all be performed at many veterinary practices, and all treatments have a relatively high success rate. If inflammatory bowel disease is diagnosed early, Goldstein reports that prognoses are good in most cases.