Liver Disease in Dogs: Types of Hepatitis

Liver Disease in Dogs
Wyatt Robinson
Written by Wyatt Robinson

The liver is a vital organ for both humans and dogs. It is not possible to survive in the absence of a liver. If organs like spleen, genitalia, some parts of the stomach and intestines are removed, a dog can still live a happy life. This cannot be said in case of liver disease in dogs because the liver performs many essential functions in their bodies. It is placed in a central position, so the blood passes through the liver and exchanges certain substances with the liver tissue.

Toxic substances of internal or external origins including those from meds stay inside the liver. There is a sort of exchange because the liver also releases nutrients in the blood that are needed for other organs in the body. The liver of a dog can be affected by multiple types of hepatitis, namely acute hepatitis, chronic hepatitis, idiopathic chronic hepatitis, cupric chronic liver disease, infectious hepatitis and liver cirrhosis. Not all of them can be cured completely, but some dogs can recover.

Acute liver failure in dogs

In case of acute liver failure, all the hepatic functions of a dog are affected as a result of multiple sudden and severe aggressions that target at least 70 to 80 percent of its hepatic function area. Clinical and laboratory tests reflect liver damage, but they cannot provide a specific cause every time.

Liver disease

The etiology of acute liver failure can be systematized in toxic agents, biotic agents, such as bacterial, viral and parasitic, systemic diseases, miscellaneous, such as liver rupture, heart stroke, shock, and so on. Veterinarians cannot identify the specific cause in most cases.

Causes of acute liver failure in dogs

A dog’s hepatic impairment can be triggered by a large number of industrial and biological toxins. The consumption of such toxins can often go unnoticed in case of dogs that are not always supervised by their owners. When the hepatic necrosis is severe and massive, a dog’s general state degrades so fast that its death can occur within 3 to 4 days. In addition, many medications can have toxic effects on the liver of a dog. Toxicity depends on the dose and the duration of administration, the liver’s condition before treatment and the sensitivity level of each dog breed.

Symptoms of acute liver failure in dogs

When a dog is also affected by systemic diseases, such as pancreatitis, hemolytic diseases, septicemia and others, their symptoms also involve serious liver damage. Anorexia, lethargy, vomiting, diarrhea, polyuria, which means excessive peeing, polydipsia, which means excessive thirst, jaundice, bleeding and hepatic encephalopathy are among the possible signs of illness.

Diagnosis of acute liver failure in dogs

The diagnosis is confirmed by enzymatic and hematological examinations, as well as by analyzing an ultrasound or a radiograph of the sick dog’s liver.

Acute liver failure in dogs

Among the other possible tests are a biopsy, bacterial cultures, serological tests, the examination of the ascites fluid and an angiograph.

Treatment of acute liver failure in dogs

The therapeutic principles are:

  • Fluid therapy: rehydration and the correction of the acid-base and mineral imbalance
  • Prevention and control of hypoglycemia
  • Nutritional support: calories, vitamin and mineral. Diet is adapted to complications.
  • Control of hepatic encephalopathy
  • Control of gastrointestinal bleeding, anemia and blood coagulation
  • Control of syncope, which refers to fainting and consciousness
  • Preventing infections
  • Control of ascites and edema
  • Control of gastrointestinal ulcers

Acute hepatitis in dogs

Acute hepatitis is a dog liver disease that has a much lower incidence than chronic hepatitis. However, its severe forms usually have poor prognosis. A study conducted in 2009 on 101 dogs revealed an incidence of 21 percent of acute hepatitis.

Acute hepatitis in dogs

Of all animals diagnosed with hepatitis, only 0.5 percent were affected by primary forms of hepatitis, while the cases involving secondary forms were more numerous.

Causes of acute hepatitis in dogs

The etiology of acute hepatitis in dogs includes heat shock, various infections including the viral ones, herpes, leptospirosis, metabolic acute hepatitis, toxicants and drugs.

Symptoms of acute hepatitis in dogs

Among the clinical manifestations of acute hepatitis are sudden onset, anorexia, vomiting, polydipsia, dehydration, depressed mood to progressive hepatic coma. Other signs are fever, jaundice, hematemesis, ascites, abdominal pain, possibly splenomegaly. Among the possible complications, the most severe one that can occur is renal failure.

Diagnosis of acute hepatitis in dogs

The diagnosis is established based on medical history, clinical picture and laboratory examinations.

Dog with acute hepatitis

In this regard, hepatitis evolves with cellular destructions, which determine the elevation of the transaminase’s number. The latters are a type of enzymes.

Treatment of acute hepatitis in dogs

The treatment for acute hepatitis may be etiologic, when the cause is known, and symptomatic.

  • Fluid therapy with saline solutions, glucose solutions and potassium
  • If necessary, vitamin K and fresh frozen plasma are administered to control blood coagulation
  • If necessary, treatment of gastrointestinal ulcers or ascites
  • Antibiotics in case of fever
  • Feeding is prohibited for 3 days after which the consumption of dairy and soy protein are recommended

Chronic hepatitis in dogs

The World Small Animal Veterinary Association (WSAVA) defines chronic hepatitis as the group of liver diseases characterized by apoptosis (programmed cell death) or necrosis, mononuclear inflammatory cells, fibrosis and regenerative processes. The proportions of these components vary greatly depending on the cause of the liver disease and its developmental stage.

The authors point out the evolution of liver diseases as chronic inflammations associated with increased enzyme activity for more than four months. Among the causes of chronic hepatitis are the accumulation of copper influenced by genetic causes or increased intake, infections and toxins.

Idiopathic chronic hepatitis in dogs

Idiopathic chronic hepatitis implies the existence of an affection that has an unknown cause and it is not the result of an autoimmune disease. Chronic hepatitis requires a reduction of the functional liver mass with decreased liver function, the occurrence of liver fibrosis and the development of portal hypertension.

Idiopathic chronic hepatitis in dogs

Cellular inflammation, fibrosis and portal hypertension are the ones causing biliary stasis and jaundice.

Causes of idiopathic chronic hepatitis in dogs

Idiopathic chronic hepatitis can develop with fever, increased liver sensitivity, pain, gastrointestinal disorders, malnutrition and coagulopathies. It can affect dogs of any age, but there was a higher incidence in case of middle aged dogs and those belonging to the following breeds: Cocker, Bedlington Terrier, Dalmatian, Labrador and Doberman. As for the dog’s gender, there was no predisposition for females or males.

Symptoms of idiopathic chronic hepatitis in dogs

Clinical signs of idiopathic chronic hepatitis show depression, vomiting, diarrhea, polydipsia or polyuria, which appear frequently. Jaundice and ascites are signs that appear later, but not in all patients. The manifestation of these symptoms might not be constant. It can be very intense for a while and then decrease without any obvious reason.

Treatment of idiopathic chronic hepatitis in dogs

Dietary management is an important component of therapy in case of idiopathic chronic hepatitis because the liver is the first stop in the way of food from stomach to the systemic circulation. It is known that the liver is the central organ of the general metabolism.

Dog food comparison

Given that in chronic forms of hepatitis the dog is affected by protein malnutrition, any nutritional restriction can become harmful. Therefore, specialists recommend the following diet and sometimes medication as well:

  • Proteins. All proteins must be of high quality and contain all the essential amino acids. They have to be fully digestible, not to generate the production of ammonia. Moreover, dairy proteins are ideal, as well as soy proteins. These dietary proteins have a protective role because they reduce the activity of the liver.
  • Fats. Fats are not especially recommended in chronic hepatitis. They might not be properly digested, so ingesting a small amount would be best rather than eliminating them from the dog diet completely.
  • Saccharides. All saccharides are needed in order to protect the liver when it metabolizes sugars from fats or from proteins. Therefore all sugars should be highly digestible and complex, way better than simple glucose.
  • Fibers. Fermentable fibers can reduce portal encephalopathy (abnormal brain function) in dogs. This does not apply to humans. They allow the incorporation of nitrogen in bacteria, reducing the production of ammonia. Moreover, non-fermentable fibers prevent constipation, which is an important factor for the development of hepatic encephalopathy. Therefore, both types of fibers are recommended for consumption in moderate amounts. If eaten in too large quantities they can interfere with digestion and absorption of nutrients.
  • Zinc. In humans, the levels of zinc are dramatically reduced when they suffer from idiopathic chronic hepatitis, but this was not observed in dogs. However, since zinc is involved in the metabolism of urea, the dietary supplementation with this mineral is highly recommended. Zinc also reduces the absorption of copper, which is toxic for the liver.
  • Soluble vitamins. Vitamin E has a protective effect on hepatocytes because of its antioxidant action. Although the body of a dog synthesizes its own Vitamin K, it is still necessary to supplement the intake. Conversely, Vitamins A and D are contraindicated because they could promote tissue calcifications.
  • Water-soluble vitamins. The B group of vitamins should be supplemented because the liver is constantly losing them. Conversely, Vitamin C is not supplemented because it can cause liver damage when combined with copper and iron.
  • There are specific meds that can only be prescribed by a veterinarian meant to control the clinical signs and slow down the disease’s progress.

Cupric chronic liver disease in canines

Too much copper present in a dog’s liver can cause acute or chronic hepatitis.

Dog with chronic liver disease

Some dog breeds are prone to this condition, namely Bedlington Terrier, Dalmatian, Labrador, West Highland White Terrier, Skye Terrier, Doberman, American Cocker, Spaniel Cocker, English Springer and so on.

Causes of cupric chronic liver disease in canines

The clinical picture can be acute or chronic depending on individual factors like the presence of copper in the dog’s diet, stress or the existence of other diseases.

Diagnosis of cupric chronic liver disease in canines

Diagnosing cupric chronic liver disease is difficult because the elevation of enzyme levels and the way it looks on an ultrasound are similar to that of idiopathic chronic hepatitis. The only way to know for sure is by liver puncture and by measuring the concentration of copper from the collected sample.

Treatment of cupric chronic liver disease in canines

According to specialists, the best treatment for this type of liver disease is prevention. If one’s dog is genetically predisposed to developing this disease, then it has to be fed with food rich in zinc and poor in copper.

Red meat and vegetables for dogs

Among the foods that are rich in copper are liver, kidney, heart, grain, cocoa and some vegetables. Foods rich in zinc include red meat, egg yolk, milk, peas, beans, tomatoes, rice and corn husk.

Infectious hepatitis in dogs

Puppies that are 2 to 6 months old are the most prone to getting infectious hepatitis. In case of dogs less than 2 months old and over 6 months old the responsiveness to this disease decreases and dogs rarely become ill. The virus enters the dog’s digestive tract or through its skin or its respiratory system. The main sources of infection are sick, convalescent or virus-bearing animals or contaminated water or food.

Symptoms of infectious hepatitis in dogs

Infectious hepatitis begins by elevating a pup’s temperature and it can evolve with symptoms such as diarrhea, vomiting, seizures and death that may occur in a few hours. If dogs suffer from an acute form, they have digestive disorders, diarrhea that is sometimes hemorrhagic, increased thirst and pain in the liver. They may also vomit and suffer from apathy. Sometimes, sick dogs might have hysterical states.

Treatment of infectious hepatitis in dogs

If infectious hepatitis develops really quickly, dogs might die in 2 to 4 days. However, there are cases when dogs get cured in 10 to 15 days. The solutions to infectious hepatitis are the bi or trivalent vaccines. Puppies that come from unvaccinated mothers should be vaccinated 2 weeks after birth.

The antigens received from the mother might neutralize the vaccine, so it is really important to choose the right time, according to the vet’s advice. Usually, pups that come from vaccinated moms should be vaccinated 2 to 3 months after birth. Also, for those puppies that have a good prognosis, the veterinarian can prescribe other meds depending on the stage of the disease and the symptoms presented by them.

Liver cirrhosis in dogs

Liver cirrhosis is the final stage of chronic hepatitis. It is characterized by the modification of the liver fibrosis into in abnormal structure. There are 2 distinct morphological types in cirrhosis, namely when the nodules are small, the size of a normal lobe, and when the nodules are bigger.

The first one causes regular and diffuse liver damage, while the second one causes irregular and diffuse liver damage, process which is followed by necrosis, death of liver cells and scarring. As for the treatment, it can only be symptomatic since it is the final stage and also irreversible.

Chronic hepatitis in young dogs

This type of chronic hepatitis is an idiopathic inflammatory disease that affects young and very young dogs. It can occur in isolation or in several dogs that live in the same shelter. Chronic hepatitis in young dogs is a form of cirrhosis, but which evolves rapidly. The livers of puppies appear normal in size and their capsule is smooth with the possibility of a few regenerative nodules.

Chronic hepatitis in young dogs

The etiology is unknown, but it is believed to be infectious or genetic. The clinical treatment is similar to chronic hepatitis. However, the prognosis is not too optimistic.

Conclusions for dogs with hepatitis

While hepatitis affects both humans and dogs, dogs are not really responsible if they get one type or the other. As said, some dog breeds are genetically predisposed to developing certain types of liver diseases. In their case, there is nothing much their owners can to either, except, of course, being aware of their predisposition and trying to avoid its occurrence throughout their lives. Since there are multiple types of hepatitis, the situation is not as negative as it might look.

If your dog gets sick, it might have a manageable or mild form of hepatitis. It does not have to be a serious type that leads to its death. However, you are also responsible for its well-being and you should carefully monitor its diet, its treatments for other affections and so on.

Make sure to keep in touch with the vet and always ask what to do to avoid such problems especially when you see changes in your dog’s behavior. A simple sign such as thirst or excessive urination should light a bulb in young head and make you think what could be causing them. Moreover, being afraid to exaggerate should not be among your concerns. It would be countless times better to detect a disease in time just because you are an owner who observes his or her dog carefully and also knows a few things about what could affect it.

About the author
Wyatt Robinson
Wyatt Robinson

Wyatt Robinson had a great 25-years career as a veterinarian in United Kingdom. He used to be a member of British Veterinary Association and worked in 3 pet hospitals in London and Manchester. He is shining when he sees his pets healthy and full of energy and it is his duty to help other dog owners to keep their best friends full of life.