Severe Diarrhea in Dogs: It Might be HGE

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“Severe Diarrhea in Dogs: It Might be HGE”

Contributed by Dr. Melissa Brookshire, DVM

What is HGE?It is not uncommon for dogs to suffer from an upset stomach. However, if your dog suddenly comes down with diarrhea that is severe and bloody, you need to act fast to save your pet’s life as he might have Hemorrhagic Gastroenteritis, or HGE.

HGE, is characterized by a very sudden onset of severe bloody diarrhea, often accompanied by vomiting, loss of appetite and lethargy. While the symptoms may vary somewhat, HGE is a potentially fatal disease that only your veterinarian can properly diagnose.

How is HGE Diagnosed?

Your veterinarian will likely run some tests to try to rule out other causes of bloody diarrhea. Some of these causes include:

  • Viral infections such as Parvovirus
  • Bacterial infections (Salmonella, Campylobacter, Clostridium, E.coli)
  • Parasites (Whipworms, hookworms, coccidia, giardia)
  • Pancreatitis
  • Colitis
  • Ingestion of toxins such as rat poison

Many of these illnesses are characterized by a rapid onset of severe symptoms, just like HGE. If your veterinarian rules out these other causes of bloody diarrhea, and your dog has a high hematocrit (measure of the red blood cell concentration in the blood), the diagnosis of HGE will likely be made.

When and Where Does HGE Strike?

Often there is no pattern to when or where HGE cases are diagnosed. On other occasions, HGE occurs seasonally or geographically. This past winter in Southern California saw a cluster of HGE that affected a large number of dogs (1) while another outbreak in Indianapolis occurred this past summer (2). Other outbreaks of HGE have occurred in Costa Rica (3), Long Island New York (4), and Pennsylvania (5) to name a few.

What causes HGE?

There is no known cause of HGE and therefore, unfortunately, there is no known prevention. Although HGE has been reported throughout the US, data shows that previous winter outbreaks in Southern California in 2004, 2005 and 2006 were thoroughly investigated using extensive diagnostic tests and still no cause for the bloody and watery diarrhea was found. There was no evidence that the dogs’ commercial pet food could have been the cause as the affected dogs ate a wide variety of different pet foods. (1)(6) Officials at the Los Angeles County Veterinary Public Health department are still investigating the cluster of HGE cases that occurred in their county last winter, but so far have been unable to find a cause. (1)(6)

The lack of a known cause is a difficult concept for us pet owners to accept. How can there not be a cause for my pet’s illness? Scientists will continue to try to unlock the mystery of HGE, but we may never know what causes this serious medical condition. Theories that have been investigated include stress, enterotoxins from bacteria within the digestive tract, viruses and even allergies. Experts at the ASPCA suggest that perhaps Autumn Crocus (Colchicum species) can cause hemorrhagic gastroenteritis. (7) Veterinary science simply does not know for certain.

How is HGE Treated?

Kelly Whitchurch, DVM recently treated a case of HGE. This patient, a 10 year old Schnauzer named Bo, presented with the classic symptom of HGE, severe bloody diarrhea. Bo is a senior dog and also has a history of a heart murmur, a medical condition that could complicate his treatment and recovery. His owners were quick to get him to Dr. Whitchurch and with 24 hours of IV fluid therapy and antibiotics, Bo made a rapid recovery.

Treatment for HGE may vary from home care (prescribed by your veterinarian) to hospitalization for multiple days. Blood or plasma transfusions may be required in severe cases. IV fluid therapy to prevent dehydration, along with antibiotics to prevent infection by bacteria that normally reside within the digestive system are hallmarks of veterinary treatment. Treatment is often successful if begun early enough and many dogs are well on the way to recovery within just a few days. Like any disease, very old dogs or dogs with chronic medical conditions are more severely affected and may require longer hospital stays.

When to Call Your Veterinarian

Digestive upset is a common condition seen in pet dogs. In most cases, the upset is short lived and resolves on its own. However, it is always a good idea to call your veterinarian whenever your pet is not acting normally. Your veterinarian can help you decide whether your pet needs to be seen right away.

Thank you to Dr. Kelly Whitchurch for sharing her recent case with us for this article. Dr. Whitchurch received her Doctorate of Veterinary Medicine from the University of Missouri at Columbia. She has practiced in Missouri, California and Vermont. She currently resides in Missouri with her husband, two dogs, two cats and two horses.

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(1) and
(6) Whole Dog Journal, “Bleeding at Both Ends” Volume 12, Number 7