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Clostridial Diarrhea

Clostridial Diarrhea

One of the most common infections we see here at Best Friends Veterinary Center, second only to periodontal disease, is diarrhea from a bacteria called Clostridium perfringens. Pets with this disease can have signs ranging from very mild to severe, watery diarrhea, sometimes accompanied by vomiting, belching, flatulence, weight loss and abdominal discomfort. There may be blood or mucous in the stool. The disease can be acute, which means it comes on suddenly. It can also be chronic (long term) or recurrent, depending on the particular strain of bacteria the pet has.

It is not known exactly where this bacterial infection is acquired. It is probably common among wildlife and many pets apparently harbor it in small numbers in their intestinal tracts all the time. The spores formed by the bacteria survive for years and are almost impossible to remove from the environment. Clostridium can be newly acquired when a pet sniffs the ground where another animal has been that carried the disease, or it may be present for a long time and suddenly flare up to cause disease. It may cause problems by itself or worsen the signs of other intestinal parasites or diseases.

We identify the disease by smearing a small amount of feces from an affected pet onto a microscope slide. The material is then stained and examined under the microscope. Clostridium bacteria look like little safety pin shapes in dark purple. In an acute infection there may be large numbers of them seen on the slide. Chronic cases may be more difficult to pick up.

The infection caused by Clostridium is easily treated with a course of antibiotics, though it may be slow to clear up. Several medications are effective, but we usually start with metronid-azole, as it is inexpensive and usually well tolerated. This drug is also available in a tuna-flavored suspension for cats, which is easier to administer. Anywhere from 10 days to a month’s supply of antibiotics may be needed. We usually recheck a stool sample for these bacteria after a pet has been on medication for 10-14 days and refill the antibiotics for a longer period of time if we still can see organisms under the microscope.

Other medications to control the symptoms of diarrhea may also be used, to make the pet feel better while the antibiotic is taking effect. A bland diet may be helpful in controlling signs of vomiting and diarrhea, but since fiber seems to inhibit the growth of the bacteria we may have you feed a high fiber diet for a week or two. Yogurt or pro-biotic medication helps make the intestinal environment more acidic, which also slows the growth of the bacteria.

Unfortunately, pets do not seem to develop much immunity against this infection. Pets commonly present with this disease repeatedly. Either they are prone to picking it up from their environment or it is harbored in the intestinal tract and flares up with stress or other gastrointestinal diseases. There is currently no vaccine to protect against Clostridium.

There is no evidence at this point to show that Clostridium can be passed from pets to people but as always we advise washing your hands after handling any pet wastes or cleaning the litter pan.

If your cat or dog is being treated for this disease, please be sure to administer the entire course of antibiotics and bring in a stool sample for recheck when we request it. Insufficient length of treatment frequently leads to a relapse of this uncomfortable and messy disease.

If the response to treatment isn’t as good as we’d like we may need to look for underlying problems that may be worsening the health of the intestinal tract, so additional blood or stool tests may be needed.

Please call us if your pet does not respond as expected, has difficulty tolerating the medication or you have any questions about the treatment or disease.