Ask The Vet: Why Do Dogs Get Diarrhea With Blood?
Dr. Ivana Crnec
The dog poop topic is not a glamorous one. To be honest, it is not even fun. In fact, it is stinky and more often than not, it can be gross. However, if you are a responsible dog parent, chances are you will have to deal with many stinky situations on a daily basis.
Jokes aside, your dog’s poop can give you a plethora of clues and tell you a lot about your dog’s digestive and overall health. Therefore, it is useful to keep an eye on your dog’s poop. You do not need to become a "poop patroller" and observe your dog’s poop every time he does it business. However, several inspections per week are recommended.
Types of Blood in a Dog's Diarrhea
Changes in the consistency of the poop are indicative of health issues. Additionally, the presence of blood in your dog’s stool is a concerning sign.
If your dog is producing bloody diarrhea it is definitely time to make a visit to your vet’s office. When you visit the vet you need to be prepared and explain what you observed. Generally speaking there can be two types of blood in your dog’s diarrhea:
Hematochezia: in this case, the blood is bright red. This type of blood occurs when the bleeding is located in the lower portions of the digestive tract.
Melena: in this case, the blood is dark, sticky, tarry and jelly-like. This type of blood occurs when the bleeding is located in the upper portions of the digestive tract.
Causes of Dog Diarrhea with Blood
There are several reasons why your dog may develop bloody diarrhea:
Swallowed blood: Injuries or disease in the nose, mouth and esophagus result in swallowing blood. The swallowed blood, unless digested, it can often be expelled through the feces.
Presence of intestinal parasites: Intestinal parasites, particularly protozoa such as Giardia and worms such as whipworms and hookworms are common causes of bloody diarrhea. These parasites are more common among young puppies.
The diagnosis is based on detecting the parasite (blood tests, fecal tests). The treatment includes eliminating the culprit by using anti-worm drugs.
Acute hemorrhagic gastroenteritis: This potentially fatal condition produces bloody vomiting and diarrhea. It may be caused by a bacterial toxin. It most often occurs in small, middle-aged dogs in breeds such as the Miniature Schnauzers and Toy Poodles.
Diagnosis is based on signs that the vet finds during an examination and on the absence of any history of poisoning, scavenging or swallowing foreign bodies.
Hospitalization and vigorous treatment with plenty of intravenous fluids is vital. Antibiotics are usually given to control opportunist bacterial infections.
Inflammatory bowel disease (IBD): IBD is the most common cause of chronic vomiting and bloody diarrhea in dogs. there are several different types, each of which is characterized by an increase in a specific type of inflammatory cell found in the intestines. Boxers, German Shepherds, Basenjis and Shar-Peis are more prone to developing IBD. Depending on the type the treatment includes hypoallergenic diet, antibiotics, parasite control and corticosteroids.
Infectious diseases: such as parvovirus, corona virus and distemper.
Parvovirus – this infectious organism has a special ability for attacking rapidly dividing cells (such as those in the lining of the gastrointestinal tract) and produces vomiting and profuse bloody diarrhea. The diagnosis requires finding the virus or its antigens. Intravenous fluids and pain control are essential. Antibiotics are given to prevent secondary bacterial infections. All dogs should be vaccinated against parvovirus as pups, and then revaccinated according to their risk and efficacy of the vaccine used.
Corona virus – this virus is a minor cause of bloody diarrhea in dogs. It is sometimes found in association with parvovirus, making that infection more serious. The treatment is symptomatic (aggressive fluid therapy, antibiotics and supportive care).
Distemper – this illness produces bloody vomiting and diarrhea. A diagnosis of distemper is made by finding the virus in epithelial cells. The treatment focuses on relieving the signs because there are no available drugs that are active against the virus itself. Vaccination against distemper is highly effective and has dramatically reduced the incidence of this disease in developed countries.
Bleeding in the stomach/intestines: Ulcers are a very common cause of bleeding. Dogs with ulcers vomit intermittently, appear unhappy, lose weight and produce bloody diarrhea. Ulcers are diagnosed with endoscopy, contrast x-rays and ultrasound. The cause of the ulcer needs to be eliminated. A combination of drugs is used to protect the mucous lining and to enhance tissue repair.
Internal bleeding due to drugs/poison: Prolonged use of non-steroid anti-inflammatory drugs (NSAIDs) often results in bloody diarrhea. It is recommended to only use NSAIDs that have been licensed for veterinary use, because these drugs are safer for dogs than many NSAIDs licensed for people.
Warfarin poisoning also results in bloody diarrhea. The treatment includes using specific antidotes (vitamin K) and providing supportive care (fluids and symptomatic therapy).
Internal bleeding due to foreign objects: Dogs foolishly swallow things like toys, bones, pebbles, fruit pits, food wrappers and just about anything else they can come across. If these swallowed objects damage the walls of the gastrointestinal tract, bloody diarrhea is likely to occur. The treatment includes surgical removal of the swallowed foreign object and repair of the damaged tissue.
Rectal polyps and tumors: Rectal polyps (adenomas) and tumors (adenocarcinomas and lymphomas) often become damaged and bleed. A vet will diagnose the presence of a rectal polyps and tumors by physical examination, endoscopy and biopsy. Both polyps and tumors require surgical removal.
Your dog’s poop can tell you a lot about its digestive system and overall health. More often than not stool problems indicate more serious and even life-threatening conditions. Therefore, it is important to observe your dog’s stool and take appropriate measures if something wrong appears.
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia.