Inflammatory bowel disease in the Dog Inflammatory bowel disease (IBD) usually refers to a chronicinflammatory disease anywhere in the gastrointestinal (GI) tract, including the stomach, small intestine (duodenum, jejunum,ileum), and large intestine (colon) The term implies a process of long duration as opposed to sudden onset. Because IBD affects many areas of the GI tract it probably has many different causes. More traditionally, IBD has referred to chronic inflammation of the small or large bowel excluding the stomach. The disease is classified by the predominant inflammatory cell found invading the wall of the bowel.
Such classification may allude o its cause. However, this method of grouping is not always possible and location of the leison will help its classification.IBD is usually found in younger dogs but, it can extend to middle age dogs. There is no strong relationship by breed however, IBD does seem to affect some breeds more often than others.The most common form of IBD is lymphocytic-plasmacytic IBD (LPIBD). This term describes the cells that are found microscopically when a biopsy of the leison is examined. Most biopsies are obtained by abdominal surgery or by endoscopy if available. Biopsies are important to rule out other causes such as: dietary hypersensitivity, lymphoma, histoplasmosis (a fungus), bacterial infection or overgrowth, and malassimilation problems.
The predominant cell type, lymphocytes and plasma cells represent a chronic stimulation of the immune system. Because of this response, IBD is typically thought of as an immune mediated disease and therefore treated with the various immunomodulating therapies. Current thoughts are that the GI tract has been sensitized by some bacteria or food antigens that determines the ongoing immune response. Complexes are formed from antibodies against food antigens,bacteria or bacterial byproducts. These antigen-antibody complexes(ABC) induce therelease of destructive chemicals into the area and tissue destruction results.
The destruction is indiscriminant. The quantity of ABC¹s produced may influence the long standing nature of the disease.Signs of IBD are dependent on the location of the problem. Disease in the stomach or upper small intestine are frequently associated with chronic vomiting and weight loss. Diseases of the jejuenum, ileum, and colon are associated with chronic diarrhea, weight loss and infrequent vomiting. Small bowel diarrhea is often watery with a large volume of feces and the patient acts sick. Large bowel diarrhea is associated with straining, some blood, mucus, small volume of feces and frequent attempts to defecate. Once IBD is suspected, strict dietary changes are fundamental for long term results. Often diet will control the disease but in the majority of cases anti-inflammatory drugs are added to quiet the immune system.
Often, the use of anti-inflammatory drugs at the beginning is enough with controlled diet to stabilize the chronic inflammation. However, the disease in most cases goes into periods of remission with repeated flare ups. Certain breeds (Wheaton Terriers and Basenjis) are more predisposed to progressive disease.Diet is chosen to produce the least amount of ABC stimulation. A true hypoallergenic diet should contain a very good single protein source that is highly digestible, so as not to be available for immune stimulation. There are now commercial diets available through veterinarians and some knowledgeable pet food stores that contain only one source of a hypoallergenic protein such as lamb, rabbit, turkey, venison, fish or duck. Many diets listed as hypoallergenic contain other ingredients and caution is order.
These are usually combined with a good source of carbohydrates such as rice or potatoes. Commercial diets insure that essential vitamins, minerals and fatty acids are included. Fiber is often a vital component of long term care. Quality fiber aids in the development of beneficial colonic flora and enhances the digestive process. In addition, diets free from preservatives and food additives may provide relief for some patients that are sensitive to these chemicals.Anti-inflammatory therapy involves immunosuppressive drugs, metronidazole, or Salycilates. The mainstay of anti-inflammatory drugs are corticosteroids. Prednisone and methylprednisolone are powerful anti-inflammatory drugs that can produce impressive results. They have minor short term side effects that include increased drinking, eating and urinating. Long term, these drugs can cause Cushing disease if alternate day therapy can not be achieved for control of IBD. Sulfasalazine is commonly used to control large bowel IBD. It has no long term side effects, however it can cause a dry eye syndrome and occasionally will cause salicylate toxicity.
Metronidazole is used because it is anti-inflammatory, anti-protozoan, and is a good antibacterial for the small bowel. The only side effect is vomiting. Other drugs that are being tried include cyclosporine and eicosapentanoic acid, a fatty acid found in fish oil. Eicosapentanoic acid is a drug often used in veterinary medicine to decrease the inflammatory response of inhaled allergies. The only side effects are a shiny coat. IBD involves a great deal of patience by the dog owner but most dog will gain relief with some variation of therapies. The disease is life long and will require regular attention.SOY PROTEIN AND IBD
Dr. Olivier Dossin, of the National Veterinary School in Toulouse, France, presented the preliminary results of a study on treating inflammatory bowel disease (IBD) in dogs. IBD is a common cause of vomiting, diarrhea and weight loss. Dietary hypersensitivity is believed to be one cause of IBD.
The study results suggest that using soy isolate hydrolysate as the main protein source in a commercial dog food has clinical use in the treatment of inflammatory bowel disease.
The eight dogs chosen for the studyhad one or more of the clinical signs of IBD, which include vomiting, diarrhea, and weight loss, in addition to having had biopsies that confirmed they had IBD. Initially, change in diet was the only treatment for the dogs, and it resulted in clinical resolution in five of the eight dogs.
After four weeks on the diet, two of the three other dogs required treatment with metronidazole.
The remaining dog also reuired treatment with metronidazole, followed later by the addition of prednisolone. These three dogs also stayed on the diet during this additional treatment.
All eight dogs experienced clinical resolution within four to sixteen weeks of the study's initiation.