The liver is unique in that it has a large reserve capacity along with some regenerative capacity. Therefore, it is actually possible to successfully treat feline liver disease if the diagnosis is made early, depending upon the underlying cause of the problem. The goals of treatment are to eliminate any harmful agents or minimize their detrimental effects on the liver, promote healing and regeneration, prevent or control complications of liver dysfunction, treat the underlying cause when possible and keep the cat as comfortable and stable as possible until sufficient liver functioning is re-established.
Treating Liver Disease in Cats
Treatment protocols for cats with liver disease will vary based upon the cause of the disorder. Liver disease in cats can be caused by fibrosis, congenital vascular disorders, a wide variety of toxins, biliary tract disorders, abscesses and various types of neoplasia (cancer). Of the cancers, cholangiocellular carcinoma and hepatocellular carcinoma are the most common types of primary liver tumors in cats, although they are not especially common. Many forms of cancer can metastasize to the liver as well. Liver disease can be acute in onset or chronic. While treatment options vary depending on the underlying cause of disease, they will often include some or all of the following approaches, and treatment will often be life-long.
Dietary adjustments are normally recommended to ensure that a cat with liver disease gets the calories and nutrients necessary to support liver regeneration and manage the signs of hepatic encephalopathy. These diets can be commercial or homemade and tend to contain very digestible, high-quality but restricted levels of protein, to reduce metabolic demands on the liver. Protein restriction is important to reduce the levels of circulating ammonia, which is caused by bacterial breakdown of protein in the gut. Your veterinarian might prescribe a particular diet with regulated portions of carbohydrates, vitamins, proteins, minerals and fats. Dietary sodium should be restricted in cases of abdominal fluid retention. In addition to dietary changes, your veterinarian might suggest vitamins and other supplements that may improve liver functioning and promote regeneration, such as Vitamin E, Vitamin C, Vitamin K, Zinc, S-adenosylmethionine (“SAM-e”), milk thistle (silybin) and/or Ursodiol.
For inherited liver disorders associated with excess copper accumulation, the amount of ingested copper must be minimized. Your veterinarian can recommend several commercially available diets and/or diets that can be made at home that contain restricted copper.
In some cases, drug therapy is appropriate to treat liver dysfunction in cats. Glucocorticoids (“steroids”) have been reported to prolong survival times in some cats with liver disease, due to their anti-inflammatory and immunosuppressive effects, although their use and appropriate dosage protocols are controversial. Antibiotics are sometimes prescribed to combat bacterial infections, especially if hepatic abscesses are present. Certain anti-fibrotic drugs have been used to combat liver fibrosis. Studies of these drugs in people show remarkable improvement in clinical signs and survival rates. Some companion animals have been shown to benefit from their use as well, although reported side effects include diarrhea, vomiting and abdominal discomfort. Other medications might be recommended to relieve vomiting, gastrointestinal bleeding and ulcers, if these signs are present.
Lactulose is commonly prescribed for companion animals with hepatic encephalopathy to increase gastrointestinal tolerance of proteins. Lactulose is broken down by bacteria in the colon and traps ammonia molecules there, making them non-absorbable and therefore excreted in the feces. Lactulose also changes bacterial metabolism so that less ammonia is generated in the first place. If the cat has seizures associated with liver disease, barbiturates such as phenobarbital may be recommended, although generally barbiturates should be avoided in cases of liver disease. Other medications will no doubt be developed over time to help treat the causes and consequences of liver disease. Drugs that require metabolism by the liver to become effective (or to be eliminated by the body) should be avoided, and all drugs should be prescribed conservatively and in moderate doses in cats with liver disorders.
Sometimes, liver disorders are treated only with supportive care, although usually supportive care accompanies rather than replaces other treatment options. Intravenous or subcutaneous fluids may be given to correct dehydration and restore proper electrolyte balance. Antacids or other medications for taxing symptoms like vomiting and diarrhea can be administered. Of course, a safe, calm, temperature-regulated environment and a healthy diet with free access to fresh water are essential.
Blood transfusions may be necessary for cats with severe bleeding disorders associated with liver disease. Only fresh whole blood or fresh packed red blood cells should be used, because stored blood products contain high ammonia concentrations, which is undesirable in cases of liver disease as it can exacerbate the behavioral and neurological signs associated with hepatic encephalopathy.
When the diagnosis involves an identifiable solitary liver mass, the treatment of choice is surgical removal. Hemorrhage is the most common complication of these surgeries, and fresh blood products should be available in case transfusion is necessary during or after surgery. Cats with liver disease are anesthetic risks, because most anesthetic agents are processed in the liver. Chemotherapy can be used for some forms of liver cancer as well. Unfortunately, treatment options are very limited for cancer which affects more than one lobe of the liver.
Newer Treatment Options in Development
Efforts are being made to explore new treatment options for companion animals with liver disease - especially for those with hepatic cancer. These include intra-arterial chemotherapy, trans-arterial chemoembolization, percutaneous ethanol injections, microwave coagulation and various immunotherapeutic strategies. While these potential therapies are beyond the scope of this article, you might discuss them with your veterinarian if your cat is diagnosed with hepatic neoplasia.
The liver is a remarkably complex organ that can malfunction and yet recover in multiple ways. Specific treatment protocols and an accurate prognosis will depend upon the type and cause of the liver dysfunction in a given animal. Only a veterinarian can assess which treatment methods are best in any given case of feline liver disease.