FATTY LIVER in HCV/HIV Coinfection
What
is fatty liver?
Fatty
liver is not a disease, but a pathological finding. A more appropriate term is
fatty filtration of the liver.
What
causes fatty liver?
Fatty
liver can be caused by certain chemical compounds, nutritional or endocrine
disorders, and by genetic factors. Drugs and chemical compounds that can cause
fatty liver include alcohol, tetracycline, methotrexate, valproic acid,
cortisone and cortisone-like medications, carbon tetrachloride, and other
solvents. Of these, alcohol is by far the most common cause. Liver inflammation
may accompany exposure to these toxins and is responsible for the associated
symptoms of fever, fatigue and jaundice.
Nutritional
causes of fat in the liver include starvation, malnutrition, or obesity. Fat in
the liver can also occur with rapid or extreme weight reduction such as might
occur following an intestinal or gastric bypass operation for obesity. In some
patients with fatty liver the fat is accompanied by inflammation (steatohepatitis),
and occasionally the fat and inflammation may lead to scarring of the liver
(fibrosis).
The
endocrine causes of fatty liver include diabetes mellitus, elevated cholesterol
or triglycerides, and fatty liver of pregnancy. Fatty liver during pregnancy
occurs near the end of pregnancy and may result in premature delivery or
termination of the pregnancy.
How
can fatty liver easily be identified?
Fat
in the liver usually does not produce any specific signs or symptoms.
Occasionally patients will experience a dull pain in the right upper abdomen.
Blood tests may reveal an elevation of the liver chemistries (SGOT or AST, SGPT
or ALT, GGT, Alkaline phosphatase). A fatty liver may be detected on an
ultrasound, CT, or magnetic resonance (MRI), examination of the liver.
Confirmation of the diagnosis requires a liver biopsy. In mild cases, where
the
patient has no symptoms and the liver chemistries are normal or minimally
elevated, a biopsy may not be required.
How
does fat get into the liver?
Fat
enters the liver from the intestines after being digested and modified by the
cells lining the intestinal wall. Fat derived from fatty tissues elsewhere in
the body may also enter the liver. Patients unable to break down or process fat
being transported to the liver can develop abnormal fat accumulations within
liver cells and the entire liver (steatosis).
Can
fatty liver lead to other liver diseases?
Fatty
liver associated with alcohol ingestion can progress to more severe disease
including alcoholic hepatitis and cirrhosis.
In
people who do not drink, fatty liver associated with inflammationand scar
tissue, nonalcoholic steatohepatitis (NASH), infrequently leads to cirrhosis.
How
is fatty liver treated?
Treatment
of fatty liver depends on the cause. A fatty liver due to alcohol can be
reversed if alcohol ingestion is stopped. Likewise, a fatty liver caused by drug
ingestion or chemical exposure can be reversed if the drug is stopped or the
chemical exposure stopped.
Fatty
liver due to obesity is best managed with a program of weight reduction,
consisting of a nutritious, low fat diet, and exercise. In patients with
diabetes, fatty liver is managed with diet and better control of blood sugar. In
individuals with elevated cholesterol or triglycerides, diet therapy is
prescribed first. Patients not responding to diet, and in those with severe
elevations of cholesterol and triglycerides, specific medications to reduce the
these levels may be prescribed (e.g., Questran, Colestid, Lopid, Lipitor,
Pravachol, Lescol, Zocor, Mevacor). Be cautious with these medications if a
person has HIV. HIV HAART medications may interact with these drugs that can
reduce cholesterol and triglycerides. This interaction can result in an unsafe
change in the drug levels of either the HIV drugs or the lipid lowering
medications. Niacin is generally avoided because of its tendency to cause liver
test elevations by itself. Some patients may be treated with dietary
supplements. (e.g., lecithin, L-carnitine). L-carnitine may enhance fat
metabolism by the liver, whereas lecithin may prevent some of the tissue damage
caused when oxygen reacts with fat during routine chemical reactions in the
liver (lipid peroxidation).
Since
many medications can cause liver test abnormalities, close follow-up with a
physician is recommended.
How
can I avoid fatty liver?
Do
not drink to excess...
In
particular, avoid concentrated sweets, saturated fats, and foods high in
cholesterol (heart healthy diet). Whenever possible use monosaturated fats
(olive oil, canola oil), instead of polyunsaturated fats.
Seek
medical advice...
Your
physician or a nutritionist working with a physician can guide you as to
appropriate diets to follow. Multivitamin supplements and vitamin E (< 1000
IU/day) may be used. Avoid large doses of vitamin A; vitamin A in large doses
may cause liver damage.