What is hepatic lipidosis?
Also known as "fatty liver disease", hepatic lipidosis is the most common cause of liver disease in cats. It occurs a cat becomes anorexic (stops or reduces the amount of food he is eating), and the body begins to use fat (triglycerides) stores as fuel. This fat is sent to the liver to be processed into lipoproteins. However the cat's liver is not very good at processing fat and it begins to accumulate in the liver cells (hepatocytes), overwhelming it and interfering with its ability to function properly. Hepatic lipidosis is split into two categories.
Primary hepatic lipidosis (also known as idiopathic hepatic lipidosis) occurs when no underlying medical cause can be found. Middle-aged and obese cats are most often affected by primary hepatic lipidosis. Stress is a major contributing factor to cats becoming anorexic.
Secondary hepatic lipidosis occurs as a result of an underlying medical condition such as diabetes, inflammatory bowel disease, cancer, cholangiohepatitis, pancreatitis or kidney disease, which causes a loss of appetite.
What are the symptoms of hepatic lipidosis?
In the early stages, there may be no signs of hepatic lipidosis other than anorexia. This is why it is so important that cat owners are aware of their cat's eating habits and seek medical advice urgently if your cat stops eating.
- Loss of appetite (anorexia) for a duration of 7 days or longer
- Weight loss
- Muscle wasting
- Excess drooling (due to nausea)
- Jaundice (yellow colour to the skin and mucous membranes)
- Poor coat condition
How is hepatic lipidosis diagnosed?
Your veterinarian will perform a physical examination of the cat and ask for a history. He will wish to perform some diagnostic tests, including:
- Biochemical profile to check serum levels of liver enzymes and bilirubin, which may be markedly elevated. 
- Ultrasound or x-ray of the liver may be performed which may reveal an enlarged liver (hepatomegaly).
- Complete blood count may reveal destruction of red blood cells (hemolysis) and abnormally sized red blood cells (poikilocytosis).
- Biopsy or fine needle aspirate, which will reveal liver cells that are swollen with lipid.
How is hepatic lipidosis treated?
If caught in time, approximately 70% of cases can be reversed. Untreated, hepatic lipidosis will lead to death in almost all cases.
Treatment depends on the severity of disease and any underlying medical conditions. Aggressive nutritional support will be required to save the cat. Prognosis is guarded until the cat is voluntarily eating on his own.
Treatment occurs in two phases.
Phase 1-Stabilising the cat (hospital care)
- Intensive nutritional support. Most frequently this involves feeding a calorie dense, high protein food via a feeding tube either directly into the stomach or esophagus. Small meals are given 6-8 times a day to help prevent vomiting.
- Anti-nausea drugs to control vomiting.
- Intravenous fluids to treat dehydration.
- Potassium may be added to intravenous fluids where necessary.
- Antibiotics may be prescribed to treat a possible underlying infection.
- Vitamin K may be given to cats, many of whom have abnormal blood clotting as a result of impaired liver function.
- Other supplements may include taurine and vitamin B-12 which can help stimulate the appetite.
Phase 2-Long term supportive care (at home)
- Once your cat has been medically stabilised, he will be sent home with a feeding tube and the owner will need to continue to support him nutritionally until he is able to eat on his own. Food will need to be warmed slightly prior to administration. The feeding tube will need to be cleaned before and after every meal. During this time, the cat should be offered food to see if he will eat on his own, once he is reliably eating of his own accord, the feeding tube can be removed. It can take around 6 weeks for the appetite to return to normal.
- Antibiotics may be continued for 2-4 to support liver function.
Obese cats who have recovered should not be allowed to regain the extra weight. In recovered cats who are still overweight, a slow weight loss programme should be started under the close eye of your veterinarian to avoid recurrence.
Cats who have had hepatic lipidosis are at greater risk of developing it in the future, so owners need to be watchful for signs of anorexia.
How can I prevent hepatic lipidosis in my cat?
- Be aware of your cat's eating habits and if you notice your cat eating less or nothing at all seek veterinary advice immediately.
- Never put your cat on a diet without close veterinary supervision.
- Try to prevent obesity in your cat, under close veterinary supervision.