What is colitis?
Simply put, colitis is an inflammation of the colon.
What and where is the colon?
The colon is another name for the large or lower intestine.
As food travels through the dog’s body, most of it is absorbed and used by the body as fuel or is stored at fat. The remaining food, composed mainly of indigestible fibers, enters the colon.
There are three functions of the colon: storing stool, absorbing water, and further digestion of unabsorbed nutrients. The colon’s bacteria count is approximately ten times denser than the bacteria in the small intestine. The bacteria take the left-over fibers and break them down into three bio-chemicals: acetate, propionate, and butyrate. These nourish the cells of the colon (which have a life expectancy rate of one week), and control the ph balance so that the toxins that are excreted will not be reabsorbed as well as producing gasses and pigments used in creating stools.
What are symptoms of colitis?
Since your dog can’t tell you what it’s feeling, you must rely on visible and tangible signs to gauge its health. A major obvious symptom of colitis is diarrhea. To properly classify and treat colitis-related diarrhea, it must be determined whether the problem is in the small intestine (which is the more serious of the two) or in the large intestine. The following characteristics are commonly found in diarrheas of the large intestine:
- They have nothing to do with weight loss
- They often involve straining and a sense of sudden urgency
- Fresh blood can often be found in the stool
- The presence of slime or mucus is often observed
- Stools often start normal and finish loose
- The stool is often gooey or slimy as opposed to watery
While your veterinarian can make a diagnosis of colitis based on the above symptoms, treatment depends on the nature of the diarrhea. Is it acute (i.e., has it appeared suddenly), chronic (ongoing for several weeks), or episodic (recurring time after time)?
Sudden (acute) colitis
If your dog suddenly develops colitis, it is probably induced by stress, such as boarding, moving, severe weather or some other change in lifestyle, or it could be from a dietary indiscretion, such as emptying the garbage can, too many treats or a sudden change in diet. These cases can usually be cleared up with proper medication and/or diet therapy. The veterinarian should also check for parasites as they can cause colitis.
Chronic or episodic colitis
If your dog’s symptoms have persisted for a month or more, your veterinarian will want to discover the cause of the colitis, and will run some simple tests. The tests will include evaluating your dog’s blood chemistry, a red and white cell profile (called a CBC), and a fecal test for parasites. He may also need to test the pancreas for its ability to produce digestive enzymes. A fecal smear or cytology test should be performed under the microscope to check for pathogenic bacteria that can cause colitis (especially the Clostridial organisms).
Whipworms are a common cause of colitis in dogs, but they are difficult to detect. If your veterinarian suspects whipworms, he may suggest treating the dog for the whipworm and see it that resolves the problem.
If the problems return after being treated, your veterinarian may recommend a colonoscopy with a biopsy in order to reach a diagnosis.
The best way to manage colitis is to get an accurate diagnosis and use the specific therapy designed for that condition. If this is not possible, your veterinarian may try to treat the symptoms as they arise to control the problem. Listed below are medications and strategies that can be useful in the management and treatment of your dog’s colitis.
Metronidazole: This is an anti-inflammatory medication helpful in the large intestine as well as able to kill harmful organisms such as Clostridia and Giardia.
Sulfasalazine: This medication is a sulfa antibiotic surrounding a salicylate anti-inflammatory. The sulfa bond keeps the anti-inflammatory medication intact through the stomach until it reaches the large intestine. While it is an effective medication, some owners have trouble medicating their dogs three times a day, which is necessary.
Dietary fiber: There are three types of fiber: soluble, insoluble, and mixtures. In general, veterinarians feel colitis is a fiber-responsive disease. The fibers are broken down into food for beneficial colon bacteria and to provide nutrients for colon cells.
Fructooligosaccharides (FOS): Dog food manufacturers Iams and Royal Canin both make a prescription diet that emphasizes the addition of FOS to its formulation. FOS’s are carbohydrates connected with fructose (fruit sugar) units that attach to glucose (starch sugar) units. While most carbohydrates are digested by the bacteria of the small intestine, FOS’s, while not fibers, are digested in the same way in the large intestine and yield the same bio-chemicals as fibers. Tests have shown that this substance helps remove pathogenic (disease causing) bacteria from the large intestine and promote the growth of good bacteria.
Diets containing FOSs may help control colitis.
Elimination diet: Colitis can be caused by food intolerance, either to a specific food or to preservatives, dyes, fillers, contaminants or even the natural proteins in the food. Your dog could also have an allergy to a certain food, such as wheat or corn. The best way to pinpoint these allergies is by feeding a pure diet, one that contains no food product in your dog’s current diet. You can make your own home cooked food or you can buy one of the many allergy specific diets available today, such as duck, rabbit, or sweet potato to name a few. During the eight to ten week test period, the dog can only eat the special food, with no treats or goodies allowed. This is an easy way to determine a food allergy in your dog, and less expensive than the standard skin testing.
Treating Clostridium: Clostridial organisms are a group of anaerobic (meaning an organism that cannot survive in the presence of oxygen) bacteria that are responsible for such diseases as tetanus, botulism, and gangrene. While some Clostridial organisms normally live in the large intestine, they don’t cause problems unless the dog is stressed or has a diet change that allows them to overgrow. Once they have grown to a large number, the high level of toxins they produce can cause colitis.
Diagnosis of Clostridial disease is complicated since a fecal smear may show its presence but it is not certain that they are producing toxins. Your veterinarian may suggest additional tests, such as the reverse passive latex antigen test and/or the ELISA test, although some veterinarians dispute the accuracy of these tests. Sometimes a course of a Clostridium-killing antibiotic, such as amoxicillin, tylosin, clindamycin, and metronidazole (which has other properties to battle colitis), will be administered as a test.
Prednisone is still the leading weapon in the treatment of inflammatory bowel disease, which must be diagnosed by biopsy. Your veterinarian will sometimes suggest a trial course of Prednisone to treat the colitis.
Source: Adapted from the Veterinary Information Network, Inc