There are many possible causes of liver disease. Some can be sudden and severe, while others progress slowly over time. Any dog can be affected and this condition is serious.

When the liver is not working properly, damaging by-products of metabolism can build up in the body. At the same time, important body functions may start to fail. Other organs can be affected, particularly the brain. Because of all this, there are many possible types and symptoms of liver disease. The liver is very good at healing after being damaged, but some types of liver disease will continue to get worse over time.

What is liver disease in dogs?

The liver has many crucial functions, notably helping in digestion, eliminating toxins and producing many important proteins. The liver has a huge capacity to deal with damage and heals quickly, so minor damage may cause no symptoms or have a quick and full recovery. But when damage is severe or prolonged, many symptoms can develop. There are many types of liver disease in dogs:

Acute liver failure

This happens when there is a sudden loss of liver function. It can be a complication of long-term disease, or be due to sudden damage to the liver by:

• Poisons such as xylitol, blue-green algae or aflatoxins from mould

• Infections, such as Canine infectious hepatitis or Leptospirosis

• Side effects of drugs: some antifungals, phenobarbital or, in rare cases, Diazepam

This type of liver disease is very serious and requires immediate intensive care treatment.

Portosystemic shunts or abnormal blood flow through the liver

• Some pets will be born with abnormal blood vessels that go around instead of through the liver.

• Others will develop this as a complication of other types of liver disease.

• Anything absorbed through the gut to reach other organs, like the brain, without being processed by the liver first.

• Can cause episodes of severe disease.

• May need to be corrected with surgery.

Canine Chronic Hepatitis

• This is a type of liver disease that develops slowly over time, although symptoms may appear suddenly when liver function drops below a critical threshold.

• There may be multiple causes for chronic hepatitis, but two are most common.

  • Copper storage disease: more common in some breeds but can happen to any dog. This disease is not well understood and can be serious, but there are treatments available.

  • Idiopathic chronic hepatitis, where there is ongoing inflammation in the liver without a detectable cause. This disease cannot be cured but can often be managed and slowed, although finding the right treatment for each patient may require thorough investigations and trying different approaches.

Liver disease secondary to hormonal diseases

• The liver is a central part of metabolism, and conditions that unbalance metabolism often lead to secondary liver disease.

• This is common in patients with Cushing’s disease but can also be a rare complication of Diabetes mellitus.

• Severity will depend on the stage of disease and other complications.

Liver cancer

• The liver is a common place for other cancers to spread to, and primary cancer of the liver is not rare in older dogs.

• Symptoms will depend on the specific type of cancer, but many are serious and disease is often only detected at late stages when treatment options are limited.

Diseases of the gallbladder

• Bile is very important for digestion. It is produced in the liver and stored in the gallbladder.

• The pancreas is in this area as well.

• This proximity and communication makes it common for the pancreas, small intestine, gallbladder and liver to affect each other, and some diseases can affect all these organs at the same time.

• Obstruction of the bile duct is a rare but severe condition that can cause sudden liver failure

• Infections of the gallbladder can come from the intestines and make their way into the liver. This is rare in dogs.

Symptoms of liver disease

Symptoms of liver disease depend on the underlying cause. Many symptoms are common across different conditions.

Acute liver disease

Sudden liver disease may cause:

• Vomiting and diarrhoea

• Lethargy

• Not wanting to eat

• Excessive drooling

• Jaundice: yellow tinge to the gums, skin and white part of the eyes

• Bruising

• Weakness

• Abnormal behaviour such as head-pressing (pushing head against a wall)

• Seizures

Chronic liver disease

Long-term liver disease may cause:

• Weight loss

• Reduced appetite

• Changes in thirst and volume of urine produced

• Vomiting and diarrhoea

• Swollen abdomen

• Lack of energy

• Behaviour changes

• Blood in vomit or stool

• Bruising easily

• In rare cases, dogs may develop crusting sores on lips, nose, footpads, ears, elbows and around the eyes.

Dogs at higher risk of liver disease

• Liver disease can affect any dog, but dogs that scavenge are more likely to eat harmful things or catch infections.

• Elderly dogs are more likely to develop a mass or tumour in the liver.

• Unvaccinated dogs are at a higher risk to get Canine Hepatitis Virus or Leptospirosis.

• Copper storage disease is more common in:

• Bedlington terriers

• Labrador retrievers

• Cocker spaniels

• Doberman Pinschers

• Skye Terriers

• Standard poodles

• Springer spaniels

• Chihuahua

• Maltese

• West Highland white terriers.

Diagnosis of liver disease in dogs

Recognising recent liver damage is usually quite straightforward. After a detailed history and physical exam, your vet will request:

• Blood tests: to measure the levels of several parameters that relate to liver disease.

  • ALT (alanine transaminase)

  • AST (aspartate transferase)

  • ALKP (alkaline phosphatase)

  • GGT (gamma-glutamyl transferase)

  • Bilirubin: produced when red blood cells degrade, is normally excreted by the liver. It can also deposit on the skin, gums and the white of the eyes, and is what causes jaundice.

  • Bile acids: measured before and after a meal, are one of the best tests to assess liver function.

  • Protein, BUN and Cholesterol levels: if low can be a sign of poor liver function in long-term disease.

  • Ammonia levels: measured when brain symptoms are present, such as seizures or abnormal behaviours, to assess if the liver is the cause.

  • Coagulation tests: performed if blood clotting issues are noted or if liver disease is suspected and surgery is needed.

  • Other blood tests may be indicated if a specific problem is suspected, like hormonal disease.

• Ultrasound scan, CT scan or MRI: to check for masses and general appearance of the liver and gallbladder. These tests cannot diagnose a specific cause or or determine how severe the problem is. They allow the diagnosis of blood vessel abnormalities or gallbladder stones.

• Sampling the liver: Taking a small sample of the liver is usually the only way to know the cause of a long-term liver problem. This is often necessary to be able to choose the right treatment. This can be done by:

  • Fine needle aspiration through the skin. This only obtains a very small sample but can be enough to diagnose some conditions, such as hepatic lipidosis.

  • Biopsy through the skin. This obtains a slightly bigger sample and provides much more information, but it is very easy to miss major changes and have the wrong diagnosis.

  • Biopsy during endoscopy or surgery. This provides the most accurate information but is a more complex procedure.

Vet treatment of liver disease

Treatment of liver disease will depend on the cause of the problem. Some medications benefit most patients with liver disease:

Acute liver problems

• Removal of any toxin or drug causing liver damage (see intoxication in dogs)

• Intravenous fluids (a drip) to correct dehydration and electrolyte imbalances

• Anti-vomiting medication

• Pain medication when necessary

• Some types of infections, such as Leptospirosis, can be treated with antibiotics

Chronic liver problems

• Special diet to reduce the workload of the liver and provide nutrients to help it heal

• Medications or supplements that support liver function, such as:

  • Ursodeoxycholic acid: promotes the flow of bile and may protect liver cells from damage

  • S-Adenosyl methionine (SAMe): a supplement that is thought to help in the detoxifying functions of the liver and may help prevent further liver damage

  • Silymarin: a supplement derived from milk thistle. It has antioxidant properties and is also thought to help prevent liver damage.

• Vitamin K: if clotting is being affected or a deficiency is detected

• Copper storage disease requires specific treatment with chelators, which are medications that attach to the copper and make it easier for the body to get rid of it.

• Some types of inflammatory problems may be treated with immunosuppressive medication, such as steroids.

• Surgery may be needed for:

  • Portosystemic shunts

  • Removal of masses

  • Obstruction of the gallbladder

• Chemotherapy: if a tumour in the liver has been diagnosed

Home treatment of liver disease in dogs

• Because of the multiple functions of the liver and complexity of many liver conditions, treatment often involves balancing different aspects and interventions.

• Dietary changes and supplements are a fundamental part of the treatment of long-term disease, especially liver disease.

• Discuss diet and supplements with your vet to find the right option for your dog and make sure all aspects of the treatment plan are considered together.

• Even natural treatments may interact with liver functions or other treatments and cause unexpected things to happen. Discuss these thoroughly with your vet to avoid complications.

Can liver disease be prevented? Can my family catch it?

Liver disease has many possible causes. A healthy and balanced diet promotes liver health and also general health. Vaccines are available for two of the more serious infections affecting the liver, Canine Infectious Hepatitis and Leptospirosis.

• Although rare, Leptospirosis can potentially pass from dogs to humans. If your dog is suspected to have or has been diagnosed with Leptospirosis, discuss how to prevent this with your vet and GP and follow their instructions carefully.

Dogs on long-term medication that may affect the liver, such as steroids or phenobarbital (used for epilepsy), should have regular checks to monitor liver function and catch any potential problems early.

When to worry about liver disease in dogs

Take your dog to see a vet immediately if they develop:

• Seizures

• Yellow gums, skin or eyes

• Large amounts of blood in their vomit or diarrhoea

• Black or tarry stools

• Constant vomiting

• Weakness or lack of response when you interact with them

Speak to a vet as soon as possible if your dog:

• Develops abnormal behaviours

• Is drinking excessive amounts of water or urinating constantly

• Loses interest in food

• Develops unexplained bruises

• Is quiet or lethargic

• Has vomiting or diarrhoea, especially if containing blood.

The vets and nurses at the Joii app are always available to give you advice and answer any doubts.