Given the huge number of vital function that the liver performs, there are quite a few things that can go wrong, and these can present in many ways. This factsheet aims to give a general overview of some of the things that your vet may be investigating in your dog and to help you understand why your vet may be recommending certain diagnostic tests. Once a diagnosis has been achieved, your vet will be able to give you further details on specific conditions.

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• Chronic inflammation: chronic hepatitis is the commonest cause of liver dysfunction in dogs and the cause if often unknown. In some cases, it may be due to ‘immune-mediated disease’ where the dog’s own immune system attacks its liver. It may progress to a more end stage form of severe liver scarring called cirrhosis
• Excess copper: taking in too much copper in the diet is an increasingly recognized cause of chronic liver inflammation in dogs of all breeds Find out more with the Vetlexicon Canis Client Factsheet on copper toxicosis.
• Genetic predisposition: certain breeds are more prone to liver conditions including chronic hepatitis and copper build up in the liver due to inherited genetic factors although these are poorly understood.
• Infections: bacterial, viral, or parasitic infections, such as leptospirosis and leishmania, can damage the liver. Find out more with the Vetlexicon Canis Client Factsheet on infectious hepatitis.
• Toxins: exposure to harmful substances, such as certain medications, chemicals, or toxic foods (eg, xylitol, certain mushrooms), can harm the liver. Find out more with the Vetlexicon Canis Client Factsheet on poisoning.
• Chronic diseases: conditions such as, pancreatitis, underactive thyroid gland or diabetes can contribute to liver dysfunction. Find out more with the Vetlexicon Canis Client Factsheets on these topics.
• Cancer: both benign and malignant tumors can affect liver function.
• Trauma: physical injury to the liver can lead to acute liver injury.
• Diseases of the gall bladder and bile duct causing infections or obstruction or rupture of the gall bladder or bile duct, including a condition commoner in older small breed dogs called ‘gall bladder mucocele’ where the gall bladder fills with a large non-cancerous mucoid mass.
• Diseases dogs are born with (known as ‘congenital’ diseases): these are uncommon but can cause liver disease due to abnormal blood vessels bypassing the liver (known as congenital portosytemic shunts) or abnormalities in bile duct development (called ‘ductal plate abnormalities’).
• Acute liver diseases are usually either toxic or infectious. The commonest cause of chronic liver disease in dogs is chronic hepatitis.

The symptoms of liver diseases in dogs can be varied and may include a variety of signs:

• Loss of appetite: dogs may refuse to eat or show a significant decrease in appetite.
• Weight loss: rapid or unexplained weight loss can occur.
• Vomiting and diarrhea: frequent vomiting and diarrhea are common symptoms.
• Increased thirst and urination: dogs may drink more water and urinate more frequently.
• Jaundice: yellowing of the eyes, gums, or skin due to elevated bilirubin levels is uncommon but is a classic sign of liver disease.
• Lethargy and weakness: dogs may appear unusually tired, weak, or reluctant to move.
• Abdominal swelling (ascites): fluid accumulation in the abdomen can cause noticeable swelling.
• Confusion or disorientation: liver failure or shunting of blood away from the liver (either due to congenital portosystemic shunt or severe liver scarring) can lead to signs of altered brain function due to toxins from the gut such as ammonia gaining access to the brain. This is called ‘hepatic encephalopathy’ and can cause confusion, head-pressing, circling, hypersalivation and occasionally seizures.
• Dark urine and pale stools: changes in urine and stool color can indicate liver dysfunction.
• Bleeding Disorders: the liver produces clotting factors, so liver failure can lead to increased bleeding or bruising.

Diagnosing liver diseases involves assessing a combination of clinical signs, physical examination, and diagnostic tests. Your veterinarian may recommend blood tests to assess liver enzyme levels and overall liver function. Imaging techniques such as X-rays, ultrasound, or CT scans can be used to visualize the liver and identify any abnormalities. In acute liver disease, these may be the only investigations. In chronic liver diseases, a liver biopsy is often performed to obtain a small tissue sample for microscopic examination, helping to determine the specific cause of liver disease. This allows most effective treatment, particularly if copper associated disease or immune-mediated diseases are identified. There are several methods for obtaining a liver biopsy, including:

• Laparoscopic biopsy: also known as keyhole surgery, this method involves anesthesia and uses a laparoscope (small camera) passed through a small incision. The surgeon can see the liver and select the best area to biopsy. It is minimally invasive and collects samples of good size and diagnostic value.
• Wedge biopsy during laparotomy: performed under general anesthesia, this method is more invasive and involves surgically opening the abdomen. The surgeon can directly examine the abdominal organs and harvest a wedge of liver tissue, providing good diagnostic value.
• Ultrasound-guided biopsy: this minimally invasive method is performed under deep sedation or anesthesia, using an ultrasound image to guide a biopsy needle. It requires only a small skin nick, but the sample size is small, with a risk of missing relevant pathology and also a higher risk of unrecognized bleeding than the other two methods.

Treatment for liver problems depends on the underlying cause and severity of the condition and your vet can advise you on specific conditions. Dogs with acute liver diseases often need hospitalization and intensive care. Options for dogs with chronic disease and the milder acute cases may include:

• Dietary changes: special diets that support liver function and provide essential nutrients. Low copper diets are essential to treat dogs with copper-associated chronic liver disease.
• Medications:  supportive treatments such as anti-oxidants, drugs which encourage bile flow and anti-sickness tablets can be used in all dogs with suspected liver disease even without biopsy confirmation of disease. Other more specific and potentially effective treatments are usually only used after biopsy has confirmed the cause of the disease such as immune-suppressing drugs (steroids and others) or drugs which chelate and remove copper . Antibiotics may be used for confirmed or suspected infections but these are uncommon in chronic liver disease.
• Surgery: in cases of tumors, cysts, gall bladder mucoceles or congenital portosystemic shunts etc, surgical intervention may be necessary.
• Supportive care: intravenous fluids, pain management, and other supportive measures may be necessary to stabilize your dog.
• Treatment of concurrent conditions: any hormonal or other conditions which may be contributing to the liver disease should be treated.

While most liver diseases can not be prevented, certain measures can reduce the risk of specific liver diseases:

• Regular veterinary check-ups.
• Vaccinations: protect against infections such as leptospirosis and canine adenovirus which are important causes of acute hepatitis.
• Avoid toxins: keep harmful substances such as toxic plants and human medications out of reach.
• Healthy diet: provide a balanced diet.

If your dog is diagnosed with liver disease, work closely with your veterinarian to develop a comprehensive treatment plan tailored to your dog's needs. Regular check-ups, appropriate management, and supportive care can help your dog lead a comfortable and active life.

Providing supportive care at home is essential for managing liver disease and ensuring your dog leads a comfortable and fulfilling life. Here are some key aspects of home care:

• Dietary management: offer a diet that supports liver function and reduces liver workload. Consult your veterinarian for specific dietary recommendations.
• Hydration: ensure your dog always has access to fresh water. Proper hydration is crucial for liver health and helps flush out toxins from the body.
• Medication adherence: administer any prescribed medications as directed by your veterinarian.
• Regular monitoring: keep a close eye on your dog's symptoms and behavior. Monitor for signs such as changes in appetite, vomiting, diarrhea, jaundice, or lethargy. Regularly check your dog's weight and body condition.
• Comfortable environment: create a calm and stress-free environment for your dog.
• Exercise: engage your dog in gentle exercise to maintain overall health and prevent obesity, which can strain the liver. Short, controlled walks and low-impact activities are ideal.
• Avoid toxins: keep your dog away from harmful substances such as certain medications, plants, chemicals, and toxic foods (eg xylitol, certain mushrooms). Be cautious with household cleaners and garden products.
• Regular veterinary check-ups: schedule regular veterinary check-ups to monitor your dog's liver function and adjust the treatment plan as needed. Repeat blood tests and imaging may be recommended to assess liver health.

Contact your veterinarian immediately if you notice any sudden changes in your dog's condition. This includes refusing to eat for more than 24 hours, severe lethargy, vomiting that won't stop, or any signs of confusion or disorientation. Regular check-ups are essential to monitor the progression of the disease and adjust treatment as needed. Your veterinarian will likely want to see your dog every few months to perform follow-up blood tests and evaluate how well the treatment is working. If you feel your pet’s quality of life has decreased at any time, you should contact your veterinarian. In many cases liver disease can progress with time, and it is important that you have a good relationship with your vet. Be honest if you feel your pet is suffering and if your pet is not tolerating treatment or if you are finding the disease hard to manage at home. With the right care and support, dogs with liver problems can lead happy and fulfilling lives. By providing a supportive diet, maintaining hydration, adhering to medications, and creating a comfortable environment, you can help manage your dog's liver condition effectively.