HGE is only seen in dogs, but what is it?

Courtesy of Kootenai Animal Hospital

Little Bamboo arrived on an emergency wrapped in a towel. The elderly Yorkshire terrier was struggling to breathe, wheezing and snorting with each inhalation. Other than her heaving chest, she was limp, barely able to lift her head. “She was fine this afternoon,” her owners reported. “But when we got home tonight she had vomited and was passing blood.” Bamboo’s gums were pale purplish instead of healthy pink, indicating poor circulation, and also dry and tacky to the touch, indicating dehydration. Her temperature was several degrees below normal. These signs could be consistent with cardiac disease, but Bamboo’s heart sounded fine, other than beating very fast. As I palpated her belly, Bamboo let loose a stream of fetid, bloody liquid from under her tail.

Hemorrhagic gastroenteritis (HGE) is a syndrome only seen in dogs. The main symptom is a sudden onset of extreme bloody diarrhea, often accompanied by vomiting. One of the hallmarks is rapid dehydration, leading to a condition called hemoconcentration. The intestines become dramatically more permeable, allowing large amounts of the body’s fluid to leak into the gut. As fluid is lost, the blood becomes abnormally concentrated, i.e., the percentage of blood cells increases in relationship to the amount of plasma. This can lead to dire problems with circulation and perfusion.

No one knows for sure what causes HGE. Some studies have indicated that the bacteria Clostridium perfringens or E. coli may be involved. Other cases seem associated with ingestion of unusual foods — something nasty on the beach or rotten from the compost pile — but often there is no apparent initiating cause. Of course, how owners define “unusual ” may be part of the problem. I once saw a Chihuahua with HGE. As a young vet, who still wanted an explanation for every illness, I grilled the owners, a sweet older couple who obviously doted on their dog. “Has Chichi had anything unusual to eat? Hot dogs? Bacon?” They shook their heads no. “Could he have gotten into the garbage?” They were adamant that the pup had eaten nothing unusual … until the wife smiled and said “Only steak, mashed potatoes with gravy, and cake and ice cream for his birthday yesterday.”

Bamboo had not had such a birthday celebration, but she was showing classic signs of HGE — rapid onset, vomiting, bloody diarrhea, hypovolemic shock. I talked more with her owners and learned that the labored breathing had started several months previously, occurring in short bouts that would come and go. With this history, the respiratory problem was probably unrelated to the HGE. We would just have to take things one problem at a time. Radiographs of both chest and abdomen looked normal. (HGE does not typically cause visible changes on x-rays.) A blood test confirmed marked hemoconcentration. Small-breed dogs are most often affected, especially miniature schnauzers, poodles, bichon frisé, dachshunds, Shetland sheepdogs, Maltese, miniature pinschers, Yorkshire terriers, Pekingese, and Cavalier King Charles spaniels. It is more common in young to middle-aged dogs, but can occur at any age.

The essential treatment for HGE is intravenous fluid therapy. This means placing an IV catheter. I looked at Bamboo’s tiny leg and took a deep breath. I’ve put in thousands of catheters over the years, but a dehydrated, panting toy dog after hours without the help of a trained assistant is still challenging. I tried once. Nope. Twice. Nope. If I couldn’t get a catheter in, we would have to make do with subcutaneous fluids, i.e., putting fluid under the skin for her body to absorb slowly. In many situations subcutaneous fluids are perfectly adequate. This was not one of them. If untreated, HGE can be fatal. Even with therapy, about 10 percent of affected dogs may die. Bamboo’s life was in the balance. I switched to her other leg, said a little prayer, and made a third attempt to guide the needle in. Success!

I had discussed earlier with her family that none of the veterinary practices on the Vineyard, including mine, offer round-the-clock inpatient care. If they wanted 24-hour observation with an intensive-care facility, they would have to take Bamboo off-Island. A large specialty hospital could do more detailed evaluations and treatment. But the family opted to have me do what I could here. I started a rapid infusion of intravenous fluids, gave antibiotics and antivomiting medication, and tucked Bamboo into a cage with hot water bottles to warm her up. “Let’s see if we can get her stabilized,” I said, sending them home to wait by the phone.

Over the next few hours, Bamboo’s temperature rose closer to normal. The hemoconcentration gradually resolved. Since toy dogs are prone to low blood sugar, we watched that as well. By the end of the evening, Bamboo was feeling much better, which is a good thing as when she started moving around more in her cage, she had finally dislodged her catheter. I gave an extra boost of subcutaneous fluids and had her family take her home for the rest of the night. “Call me later if she gets worse again,” I told them. “Otherwise, I’ll see you first thing in the morning.”

The next day Bamboo was on her feet, tail wagging. She was breathing normally. We still have to work on diagnosing those episodes of respiratory distress, but her hemorrhagic gastroenteritis was resolving. With rapid diagnosis and aggressive treatment, the prognosis for HGE is usually good. “You can start her on a bland diet today,” I said, advising feeding multiple small meals for several days and then slowly weaning back onto regular food. I offered Bamboo a little piece of a liver treat, just to assess her appetite. She ate it eagerly. “You’re my hero,” one of the owners told me. If he only knew how lucky, how blessed, I felt to have gotten that intravenous catheter in on that third try. I gave Bamboo another small treat and watched her eat it up happily. Best Christmas present ever.