Diarrhea Due to Clostridium perfringens in Dogs

Clostridium perfringens is an intestinal bacteria that produces toxic compounds when it proliferates. These enterotoxins (substances that are toxic to the intestines) are a common cause of diarrhea in dogs; in fact, 34% of dogs with diarrhea have been identified as carrying clostridium toxins. The disease that results from clostridium enterotoxins is called clostridial enterotoxicosis. It is something of a mystery to veterinarians, in spite of the obvious connection to the bacteria. About 80% of dogs seem to carry the bacteria without producing toxins or showing signs of diarrhea. Symptoms seem to develop suddenly in response to a stressor such as diet change, an allergic reaction, or an environmental disturbance like staying in a hospital or a kennel. When this happens, the bacteria produce spores and proliferate toxically in large numbers. It is possible that ingestion of the bacteria in food, or exposure to other dogs may also precipitate the problem, even though some bacteria are already present in the intestine. Symptoms can vary from mild diarrhea that resolves itself in about a week, to chronic episodes that recur every few months. Some dogs can have a sudden, life-threatening form of gastritis, called hemorrhagic gastroenteritis, with acute vomiting and bloody diarrhea. This will need immediate treatment to prevent dehydration and shock. Most other forms respond to oral antibiotic.

Clostridium perfringens bacteria are common in dogs. This bacteria is often present in the intestine asymptomatically, but when it proliferates it produces spores and toxic compounds that cause diarrhea. This is called clostridial enterotoxicosis.

Take your dog to see a veterinarian if you notice any of the following symptoms. Extreme bloody diarrhea should be treated as an emergency.

• Diarrhea with mucus
• Tenesmus (straining to defecate)
• Watery stools
• Blood in the stool (hematochezia)
• Hemorrhagic diarrhea (resembling raspberry jam)
• Flatulence
• Vomiting
• Signs of abdominal pain
• Weight loss or general ill health in chronic cases

Types

Clostridium perfringens bacteria may be associated with three different types of symptoms.

• Acute – self-limiting symptoms of diarrhea lasting 5-7 days
• Chronic – recurrent symptoms occurring every 4-6 weeks (more common in older dogs)
• Hemorrhagic gastroenteritis – sudden symptoms of profuse bloody diarrhea and vomiting

Some of the following factors may precipitate an opportunistic infection. Veterinarians believe some dogs may be more susceptible to the bacteria.

• Stress (staying in a kennel or hospital)
• Diet change
• Eating food with high levels of bacteria (such as spoiled food or raw meat)
• Allergic reaction
• A higher than normal PH in the intestinal tract
• Hemorrhagic gastroenteritis is more common in small and toy breeds (Yorkshire Terrier, Miniature Pinscher, Miniature Schnauzer, Miniature Poodle, Maltese)
• Idiopathic

The veterinarian will need a description of your dog’s symptoms, including any prior problems with diarrhea and any potential stressors. Diet change or recent dietary indiscretion can be relevant. If your dog has been vaccinated, this can help to eliminate parvovirus which can cause similar symptoms of diarrhea. Dogs with parvovirus usually also have fever and more signs of systemic illness.

Bloodwork will usually be normal unless your dog has hemorrhagic gastroenteritis, in which case there will be a decreased plasma concentration from dehydration. Blood tests can also help to eliminate other potential causes like kidney or liver failure. In the case of chronic problems, x rays or intestinal biopsy via endoscopy may be necessary to rule out cancer.

A fecal sample will be necessary to diagnose the bacteria. Clostridium perfringens bacteria can be identified under a microscope. Large numbers of bacteria will suggest that they are causing your dog’s diarrhea, but, since many dogs have this type of bacteria without any symptoms, the sample will have to be sent to a lab to identify the toxin. In the meantime, the veterinarian will treat your dog’s symptoms and may prescribe an antibiotic.

Dogs that are very ill will need immediate treatment with fluids and electrolytes. Some dogs may need blood or plasma transfusion. Intravenous antibiotic may also be given to reduce the chance of sepsis developing as intestinal bacteria spread through the body.

Milder symptoms will be treated with an oral antibiotic. For cases with no prior history, medication will only need to be prescribed for about a week. Most dogs respond well to this treatment. Recurrent problems may require a low dose antibiotic for a longer period of time. A probiotic medication (such as lactobacillus) may be recommended to encourage more healthy intestinal bacteria. Diet change can also be helpful. Many dogs with chronic clostridium do better on a high fiber diet. The veterinarian may recommend a specific brand of dog food, or suggest you add fiber supplements such as psyllium or oat bran.

Clostridium perfringens responds well to treatment, even though the exact cause of the disease is still poorly understood. Dogs with short-term symptoms usually recover completely with treatment. Chronic recurrent problems may require long-term management with diet change and frequent visits to the veterinarian. Hemorrhagic gastroenteritis can be treated well with intense fluid therapy. If it is caught in time, your dog will make a complete recovery, but untreated it can often be fatal, so it’s important to watch your dog closely and get treatment immediately if you notice signs of severe diarrhea. Dogs that have experienced this disease once have a higher chance of a recurring episode. Maintaining a stable lifestyle and a regular diet can also help to avoid conditions that would cause the bacteria to proliferate.