Hepatic Lipidosis in Cats

Hepatic lipidosis, or fatty liver, is a common syndrome
characterized by excess fat accumulation in the liver of cats.
It can occur in cats of any age or breed and may affect more
females than males. Hepatic lipidosis classically occurs after a
period of anorexia (loss of appetite) of at least 2 weeks
duration. When an additional disease state is found to be the
cause of the anorexia, the hepatic lipidosis is defined as
“secondary.”

The term “primary” or “idiopathic” hepatic lipidosis is used
when an additional disease state cannot be identified. This is
the case in approximately 50 per cent of cats diagnosed with the
disorder. Obesity before the period of anorexia increases the
chances of a cat developing clinical hepatic lipidosis. The
decrease in appetite causing secondary hepatic lipidosis can
occur for a variety of reasons.

The more common of the predisposing disease states are diabetes
mellitus, pancreatitis (inflammation of the pancreas), cancer,
and other liver diseases. Behavioral or stress-related causes of
anorexia are also common; they include the owners being away on
vacation, family members leaving or new people or pets being
introduced into the household, boarding, and dietary changes.

Unfortunately, once this disease develops, cats feel ill and may
not begin to eat again even if the, initial cause of their loss
of appetite has been eliminated. Without aggressive medical
intervention, this vicious circle can, lead to death in over 90
per cent of the cats.

Cats are unique in their tendency to develop this disorder.
Excessive amounts of fat are broken down from the cat’s
peripheral fat storage tissue during fasting. This fat is then
transported to the liver. The liver should then process this fat
and export it to the rest of the body in a new form. In cats
that develop hepatic lipidosis this process is impaired and the
rate of fat export from the liver is much slower than the rate
of fat intake, resulting in liver fat accumulation. Damage to
the liver is caused by swelling of liver cells filled with fatty
deposits as well as additional processes. Symptoms commonly seen
with this syndrome are anorexia, weight loss, lethargy,
vomiting, jaundice (yellow tinge to the skin, inside of the
ears, and gums), and occasionally behavioral or neurologic signs
such as excessive drooling, blindness, semicoma or coma, and
seizures. The suspicion that a cat is suffering from liver
disease is confirmed by physical examination and appropriate
abnormalities in blood work.

Imaging techniques such as x-rays or ultrasound examination of
the abdomen are helpful in demonstrating the size and appearance
of the liver, as well as ruling out other disease states. The
definitive diagnosis of hepatic lipidosis requires visualization
of fat globules in liver cells obtained via liver biopsy or
needle aspiration.

The treatment of hepatic lipidosis varies depending on its
severity and the existence of other diseases. Prevention is
extremely important. Any anorexic cat, especially if obese,
should be seen by a veterinarian. Thus, the development of
hepatic lipidosis can be caught in its early stages or prevented
entirely with appropriate therapy. Hospitalization, fluid
therapy, and supportive care may be required initially when the
disease develops. Additional therapy such as antibiotics,
vitamin K, and the treatment of other diseases may also be
necessary.

The cornerstone of therapy, the only way to reverse the process
of fat accumulation in the liver, is aggressive feeding to
supply your cat with his or her full caloric requirements.
Offering different diets and appetite-stimulating medications
may induce a cat to eat in the initial phases of anorexia but
will most likely not be of benefit once clinical signs of
hepatic lipidosis develop.

Force feeding is usually not a good idea. Even with the most
cooperative cat, it is virtually impossible to feed adequate
amounts in this fashion. Cats also seem to develop food
aversions rapidly, and the association between food and the
unpleasant experience of forcing may delay the cat’s return to
eating. Therefore, in the clinical phase of the disease the only
reliable treatment option is tube feeding.

The use of long-term tube feeding has changed the outcome in
this disease from over 90 per cent mortality to less than 30 per
cent. There are three types of feeding tubes commonly used for
this disease. A tube placed through the nose into the stomach or
esophagus can be used temporarily. Long-term feeding is achieved
with a tube surgically placed in the esophagus or, more
commonly, a tube surgically or endoscopically placed through the
body wall directly into the stomach.

A commercially available maintenance diet is used for most cats.
Your veterinarian will supply you with a feeding plan aimed at
meeting your cat’s nutritional requirements. Additional
medications to control vomiting are sometimes necessary.
Frequent rechecks with your veterinarian will be required to
assess the tube location, possible infection, your cat’s
clinical state, and blood work. Liver parameters usually improve
within 2 to 8 weeks after initiating feeding. Oral food should
not be offered until that time.

Once your cat begins to eat, tube feedings can be gradually
reduced over a few weeks and eventually discontinued. Most cat’s
tubes can be removed 3 to 4 months after placement. In cats with
idiopathic hepatic lipidosis recurrence is rare, and the cats
that recover go on to live normal lives.

The above is general veterinary information. Do not begin
any course of treatment without consulting your regular
veterinarian. All animals should be examined at least once every
12 months.