It had been a long night for Avery’s owner. Avery is a 7 year old Bichon Frise that went from the picture of health the day before to having profuse, watery, bloody diarrhea throughout the previous night. As Avery was losing all the fluids in the bloody diarrhea, she tried to drink enough to make up for the fluid loss. She was drinking so much that she was vomiting it up as fast as she was drinking it in. All of this led to Avery presenting early in the morning at my office very lethargic and obviously seriously ill.

There are many potential causes of bloody diarrhea in dogs. Parasites such as coccidia and hookworms can cause some blood in the stool, but usually not to this extent. Parvovirus Enteritis is caused by a virus which can definitely cause profuse, watery diarrhea, but Avery was vaccinated against this virus so was very unlikely. Toxins such as mouse poison can cause bleeding anywhere in the body, including the gastrointestinal tract, but there was no known exposure to this in Avery’s environment. Avery was kind enough to pass some of the bloody diarrhea on the exam room floor so that I could see exactly what the owner had been witnessing during the night and as soon as I saw that I was quickly suspicious of another cause of bloody diarrhea, Hemorrhagic Gastroenteritis.

Hemorrhagic Gastroenteritis, or HGE, is a disease with no known cause. It starts up very suddenly and seems to come out of nowhere. It is most often seen in middle-aged, small breed dogs. With this disease, the cells that line the intestines are suddenly disrupted allowing blood, fluids and electrolytes to shoot quickly through the digestive tract causing the profuse, watery diarrhea. The disruption of the intestinal cells also causes the dogs to get nauseous and vomit. These dogs get dehydrated very quickly causing them to go into hypovolemic shock. The bacterial toxins normally confined to the intestine can then get into the blood causing septic shock. HGE is obviously a very serious disease and can easily be fatal without treatment.

In spite of the seriousness of this disease, quick and aggressive treatment usually will stabilize the condition quickly, and it is very common for the dog to be acting and feeling much better within just 1-2 days. Blood tests on dogs with HGE show severe dehydration. Normally, the percentage of the blood taken up by red blood cells is about 45%. In dogs with HGE this percentage is often 65-70% causing the blood to appear sludgy when being drawn into a syringe. The most important part of the treatment is IV fluids to replace the fluids lost through vomiting and diarrhea. Often within just hours of starting aggressive IV fluid therapy, these dogs are acting much better. They are also treated with antibiotics because of the high risk of sepsis from the severely damaged intestinal lining.

Avery responded very quickly once hospitalized and treatment was begun. She only had one large bloody diarrhea mess about 6 hours after being admitted. The vomiting stopped because while on IV fluids we didn’t have to worry about her taking in anything orally, so she didn’t have anything to vomit. Within

Twenty four hours of being admitted Avery was bright eyed again and had a definite pep in her step when we walked her. We started offering her small amounts of water which she took in without vomiting. Twenty seven hours after being admitted we began small meals of a low fat intestinal diet which she ate quickly. She then went home with directions to continue an intestinal diet for 4-5 days just over 30 hours from the time she was initially admitted. It always amazes me how quickly dogs with HGE change from near death to clinically normal.

Although Hemorrhagic Gastroenteritis isn’t extremely common, it is something to keep in mind if your dog becomes acutely lethargic and is having large amounts of bloody diarrhea. If these signs are seen in your dog, contact your veterinarian or the local veterinary emergency service as soon as possible for diagnosis and treatment.

Chad Higgins, DVM has owned Amanda Animal Hospital for the last 18 years and sees dogs, cats, ferrets, and other little furry critters.