Inflammatory bowel disease or IBD in dogs consists of a chronic inflammatory process that can affect different sections of the canine intestine, and it occurs due to an accumulation of inflammatory cells in the intestinal mucosa (lymphocytes, plasma cells, eosinophils and macrophages). Because of this, different types of IBD can occur, depending on the type of cell dominance.
In all types, the common clinical sign is chronic diarrhea The definitive diagnosis is achieved with histopathology and treatment should consist of in dietary and pharmacological therapy. If you want to know more, keep reading this article on our site to learn about this digestive pathology that can affect our dogs, its symptoms, diagnosis and treatment.
What is inflammatory bowel disease in dogs?
Canine inflammatory bowel disease or IBD (Inflammatory Bowel Disease), consists of a chronic enteropathy characterized by enteritis or inflammation of the intestine by infiltrate of inflammatory cells (lymphocytes, plasma cells, eosinophils, macrophages or combinations of these) in the mucosa of the dog's intestine.
Causes of inflammatory bowel disease in dogs
The origin is uncertain, but the existence of an exaggerated response to a series of antigens, such as:
- Intestinal microflora bacteria.
- Diet food allergens.
- Components of the digestive system itself in contact with the mucosa of the intestine.
This exaggerated response of the local immune system of the dog's intestine can be caused by an impaired intestinal permeability, leading to increased exposure of existing antigens. For its part, the inflammatory infiltrate that forms causes a lesion in the mucosa that causes greater absorption of antigens and proinflammatory substances that make the process chronic.
The intestinal microbiota can suffer alterations due to changes in absorption and intestinal peristalsis caused by the disease.
Types of inflammatory bowel disease in dogs
Depending on which cell type predominates in the inflammatory infiltrate of the lamina propria of the intestinal mucosal layer, the following types of enteritis are distinguished:
- Lymphoplasmacytic enteritis: infiltrate in the intestinal lamina propria of lymphocytes and plasma cells. This type of IBD is the most commonly diagnosed in dogs. Basenji, German Shepherd and Shar Pei dog breeds are more predisposed.
- Eosinophilic enteritis: infiltrate of eosinophils in the intestinal mucosa. It is more common in rottweilers.
- Granulomatous enteritis: infiltrate of granulomatous formations of epithelial cells. The predominant cell type is macrophages.
Sometimes the colon can be affected, distinguishing four types of colitis:
- Lymphoplasmacytic colitis: infiltrate of lymphocytes and plasma cells in the mucosa of the colon.
- Eosinophilic colitis: infiltrate of eosinophils in the mucosa of the colon.
- Granulomatous colitis: infiltrate of granulomatous formations of epithelial cells in the colon.
- Histiocytic-ulcerative colitis: especially common in boxers, it is characterized by a decreased caliber of the lumen of the large intestine, with a mucosa very thickened, irregular, eroded, congested and with areas of active bleeding.
The intestinal lymphagiectasia, characterized by edema and dilation of the lymphatic vessels, can fall within the IBD complex because it is frequent that many of these processes occur with this pathology.
Symptoms of IBD in Dogs
Dogs with inflammatory bowel disease have in common the symptomatology of chronic diarrhea, unlike cats with IBD, which show more frequently vomiting and weight loss. In addition to chronic diarrhea, dogs with enteritis or inflammatory colitis may show:
- Weightloss.
- Appetite changes.
- Nutrient malabsorption.
- Malnutrition.
- Bilious vomiting.
- Bulky stools in enteritis.
- Bloody or mucous stools in colitis.
- Intestinal rumbling.
- Flatulence.
- Abdominal pain.
- Anemia.
- Ascites or peripheral edema if protein-losing enteropathy has developed.
Diagnosis of inflammatory bowel disease in dogs
The first thing in diagnosing IBD is to rule out other differential diagnoses that may cause similar symptoms before performing an intestinal biopsy for your anatomopathological study, which is the definitive diagnosis of this disease.
To do this, in addition to a good clinical history and physical examination, the following tests should be performed:
- A blood test and biochemistry.
- Bone scan.
- Ultrasound.
- Coprological analysis.
- Stool culture.
If these diseases are ruled out, the diagnosis should be confirmed by taking biopsies. These biopsies consist of obtaining a fragment of the dog's intestine for further study. Biopsies should be obtained by endoscopy or laparotomy (exploratory surgery). Depending on the predominant cell type(s) on histopathology, the type of inflammatory bowel disease the dog is suffering from will be diagnosed.
Canine IBD Treatment
Treatment of IBD is never curative, but it is possible to control the symptoms of the animal, despite the fact that the inflammation keep persisting.
The treatment will depend on the severity of the inflammatory bowel disease and the presence of hypocobalamineemia (low vitamin B12), thus differentiating it into four indices of clinical activity with specific treatment according to the criteria:
Treatment of canine IBD with low clinical activity index
Histopathology shows no abnormalities, making IBD questionable. In addition, the albumin concentration is normal. In these cases, empirical treatment should include:
- Fenbendazol (50 mg/kg for 5 days): for possible control of Giardia and other internal parasites.
- Hypoallergenic diet with hydrolyzed or novel protein: if the signs subside, it indicates enteropathy that responds to diet or food hypersensitivity, not an IBD.
- Antibiotics: such as tylosin or metronidazole. If there is a good response, it is an enteropathy that responds to antibiotics.
Treatment of canine IBD with mild-moderate clinical activity index
There are abnormalities suggestive of IBD on histopathology, but the albumin concentration is greater than 2 g/L. The treatment in this case will be:
- Fenbendazol (50 mg/kg for 5 days): for possible control of Giardia and other internal parasites.
- Hypoallergenic diet with hydrolyzed or novel protein: for at least two weeks.
- Antibiotics: such as tylosin or metronidazole for two weeks. If there is a good response, for a month.
- Glucocorticoids at immunosuppressive doses: prednisone (2 mg/kg/24 h) for 2-4 weeks until symptoms improve, subsequently reducing the dose gradually to the minimum effective.
If the response is not adequate, add other immunosuppressants, such as:
- Azathioprine (2 mg/kg/24 h for 5 days and then 2 mg/kg every 2 days).
- Cyclosporine (5 mg/kg/24 h).
Treatment of canine IBD with moderate-severe clinical activity index
The changes in histology are quite advanced and the albumin concentration is less than 2 g/l. Treatment of severe IBD is as follows:
- Fenbendazol (50 mg/kg for 5 days): for possible control of Giardia and other internal parasites.
- Hypoallergenic diet with hydrolyzed protein.
- Antibiotics: such as tylosin or metronidazole for two weeks. If there is a good response, for a month.
- Glucocorticoids at immunosuppressive doses: if not effective, other immunosuppressants (azathioprine (2 mg/kg/24 h for 5 days and then 2 mg/kg every 2 days) or cyclosporine (5 mg/kg/24 h). If it is not effective or low intestinal absorption is suspected, injectable corticosteroids can be tried.
- Antithrombotics: If they have developed protein-losing enteropathy, adding antithrombotics such as aspirin or clopidrogel should be considered, due to that these dogs have a higher risk of developing thromboembolic disease due to the loss of antithrombin at the intestinal level.
- Cobalamin: administer cobalamin (vitamin B12) once a week for one month, and then once a month for 3 months. Then, repeat the measurement to see if it is necessary to continue supplementation or not.
In dogs with ulcerative-histiocytic colitis, the use of enrofloxacin for long periods is the indicated treatment, since this disease is associated with strains of Escherichia coli that invade deep layers of the large intestine.
