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Chronic Hepatitis
Definition
Chronic Hepatitis (CAH) is ongoing injury to the cells of the liver with inflammation
which lasts for longer than six months. The causes of chronic hepatitis are
several: viruses, metabolic or immunologic abnormalities and medications.
Symptoms
Symptoms result from the liver cell injury, the inflammation or from the resulting
scarring which is called cirrhosis. Chronic hepatitis may follow acute hepatitis
B or C (formerly called non-A, non-B) or may develop quietly without an acute
illness.
Liver biopsy is helpful in that it confirms the diagnosis, aids in establishing
the cause (etiology) and can demonstrate the presence of cirrhosis. It is less
helpful in judging the response to treatment.
Hepatitis B and C are the most common causes of chronic hepatitis. Together
they account for more than 75% of the cases in the world. Hepatitis B is far
more common in China and sub-Saharan Africa and among male homosexuals and IV
drug users.
Chronic hepatitis C behaves differently from hepatitis B. The disease is generally
mild, with fatigue being the main symptom. However, ten or more years later,
the complications of cirrhosis appear in some patients, sometimes unexpectedly.
By contrast with hepatitis B, the percentage of patients infected who develop
cirrhosis is much greater. While primary liver cancer can also develop from
hepatitis C, it appears to be much less common than after hepatitis B.
Autoimmune Chronic Hepatitis varies from mild to serious disease. The percentage
of patients who develop cirrhosis is high and it may appear early. Most of the
patients are young women but postmenopausal women and males may get the disease.
Only a few cases of primary liver cancer have been reported with this disease.
Twenty-five percent of the cases of chronic hepatitis result from damage to
the liver by the immune system. The trigger for autoimmune chronic hepatitis
is unknown, but the damage to the liver is caused by the individual's lymphocytes
and by antibodies produced in the individual's own tissue. Autoimmune chronic
hepatitis is usually a progressive disease ending in cirrhosis.
Hepatitis A and E (formerly called epidemic or enteric non-A, non-B) are rarely,
if ever, responsible for causes of chronic hepatitis.
Hepatitis D infection needs the hepatitis B virus to multiply. Hepatitis D can
cause acute hepatitis in someone who is a carrier of the hepatitis B virus and
can cause acute hepatitis at the same time that the hepatitis B virus does.
In any event, the combination of hepatitis B and D is worse then hepatitis B
alone and is more likely to cause serious chronic hepatitis and cirrhosis. IV
drug users have a high incidence of hepatitis D.
Other Causes
Viruses of the herpes family, which cause cold sores, genital herpes, chicken
pox, shingles and infectious mononucleosis, can cause acute hepatitis, especially
when the immune system is not functioning properly. It is unlikely that they
will produce chronic hepatitis. Other viruses, as yet undiscovered, may be responsible
for some cases of chronic hepatitis.
Drug-Induced Hepatitis
Few medications still in use and several that have been withdrawn from the market
can also cause chronic hepatitis. These include: isoniazid, used for tuberculosis;
methyldopa, used for hypertension; nitrofurantoin, used for urinary tract infections;
phenytoin, used for seizure disorders and selected other prescription medications.
These medications must be taken for long periods of time and the number cases
of chronic hepatitis produced by these medications is small.
Chronic hepatitis caused by drugs is usually recognized early. Stopping the
medicine before cirrhosis has developed usually reverses the disease.
Inherited Disorders
Some inherited disorders of metabolism also can appear as chronic hepatitis.
The most frequent of these conditions is Wilson's disease, a familial disorder
of copper metabolism. Alpha-1-antitrypsin deficiency and tyrosinemia may appear
as chronic hepatitis although other features help in distinguishing these rare
conditions from those caused by viruses.
Signs and Symptoms
Fatigue, mild discomfort in the upper abdomen, loss of appetite and aching
joints are the common symptoms of chronic hepatitis. Fatigue is by far the most
common symptom and it might be quite disabling. Often it gets worse as the day
wears on. Some patients, however, may have no symptoms. Others may have signs
of liver failure, inducing jaundice, abdominal swelling (due to fluid retention
called ascites), or coma, depending on the severity of the liver disease and
whether or not cirrhosis has developed. Most complications are vague and may
be mistaken for other diseases or simply a consequence of aging. Disorders of
other organs like the thyroid, intestine, eyes, joints, blood, spleen, kidneys
and skin may occur in about 20% of patients depending on the cause of the chronic
hepatitis.
When the hepatitis is mild and limited in extent, it is called chronic persistent
hepatitis (CPH). When it is more extensive and seems to be destroying the cells
of the liver, it is called chronic active hepatitis (CAH).
Treatment
Interferon has been approved for the treatment of hepatitis B and C. The treatment
has been shown to reduce the inflammation and liver damage caused by the virus
in 25-30% of cases by eliminating the virus, thus reducing the development of
scar tissue and avoiding the development of cirrhosis.
In people treated with interferon studies show that 50% will respond to treatment
and 50% of those patients will relapse when interferon is stopped. Research
is going on to address the relapse rate.
Additional clinical trials are being conducted to identify the most effective
dose and duration of therapy with interferon. Studies are continuing in an attempt
to reduce the side effects of the medication that exists. These include "flu-like"
symptoms, and less often, fever, depression, hair loss, nausea and vomiting.
Currently, the treatment consists of an injection three times a week over a
period of six months.
Blood tests are needed to monitor progress during treatment and a liver biopsy
(retrieving a small specimen of the liver through a needle inserted into the
liver) is an accepted procedure prior to and following treatment.
Fifty percent of the patients treated will experience remission of the disease.
When the treatment is stopped 50% will relapse. However, only about 20% of untreated
patients will go on to develop cirrhosis over a period of years. Research into
the management of those who relapse is ongoing.
Interferon does not seem to work well in patients :
•with substance abuse (alcohol or illegal drugs),
•who are not very sick,
•whose test results are not very abnormal,
•whose immune system is not functioning well because of AIDS,
•with hepatitis B who were infected from their mothers at birth,
•carriers who are no longer contagious or infectious,
•with significant heart, lung or kidney diseases,
•or couples who are trying to conceive.
Knowing the cause of the disease is helpful in estimating the prognosis.
Only a small percentage of patients with chronic hepatitis B develop cirrhosis.
In those patients, cirrhosis develops early in the course of the disease with
complications appearing in the first few years. Chronic hepatitis often causes
acute hepatitis or flare-ups and periods with no signs. Scarring becomes more
extensive with each flare-up. Patients in the Orient have about a 15% chance
of developing primary liver cancer, usually after the age of 50 with men more
likely candidates than women. This complication is much less common in the Western
World.
The disease becomes life-threatening only after cirrhosis has developed. More
than half of all patients live at least 15 years from the time of the first
diagnosis and this number is continuously improving. Previously, prognosis was
thought to depend on what was found on liver biopsy. This is now only partly
true. Prognosis is worse and complications more numerous and severe if cirrhosis
has already developed. Much attention has been paid to the location and extent
of the inflammation of the liver.
Steroid therapy remains the only useful treatment for autoimmune disease, but
it may have to be given for a lifetime and may also not prevent the ultimate
development of cirrhosis.
Liver transplantation has become an accepted form of therapy when chronic hepatitis
becomes life-threatening, usually as a result of complications of cirrhosis.
Recurrence of hepatitis C or autoimmune hepatitis does not seem to occur, but
hepatitis B, if virus is still present and the patient is contagious, will recur
in the new liver and often be acute. Attempts are being made to prevent this
recurrence.
The most important treatment for hepatitis B is prevention. Hepatitis B vaccines
should be given to all who are exposed to this disease on a regular basis. All
pregnant women should be tested for hepatitis B. Carriers of hepatitis B, many
of them unaware that they are infected, can pass it on to their babies as well
as their sexual contacts. All newborns should be vaccinated against hepatitis
B. Three injections are needed to provide adequate immunity.
An important aspect of treatment is supportive care. Diet should be well balanced.
The use of high carbohydrate, high protein or low fat diets have no scientific
basis, and in some instances, such diets may be harmful. Vitamin and mineral
supplementation also has no place in the management of chronic hepatitis unless
some deficiency is present. No substance is known that will help the main symptom,
fatigue. However, a good physical fitness program may lessen this distressing
symptom. Patients should be advised to limit the amount of salt that they use
in an attempt to forestall the accumulation of fluids as ascites or ankle swelling.
Since almost all drugs must be detoxified by the liver, and since the injured
liver does not perform this task well, limiting the amount of drugs that a patient
uses to only essential ones is important. This includes discouraging the use
of sedatives and tranquilizers.
Looking to the Future
Learning more about the viruses responsible for chronic hepatitis and how to
control them will occur in the next decade. Similarly, learning about the body's
immune system and how to control it has already begun. Preventive efforts will
be enhanced so that fewer cases of chronic hepatitis will develop. The goal
of eliminating this group of diseases seems to be just over the horizon, and
while our skills at transplantation are rapidly increasing, the form of therapy
for chronic hepatitis, like the disease itself, will disappear.
American Liver Foundation
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