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Five
different viruses (termed A,B,C,D, and E) cause viral hepatitis. Three
other viruses that cause hepatitis have been identified, but not much
is known about them. Hepatitis C virus (HCV) is known to account for
the great majority of what was previously referred to as non-A, non-B
hepatitis. The hepatitis C virus was identified and described in 1989,
and in 1990 a hepatitis C antibody test (anti-HCV) became commercially
available to help identify individuals exposed to HCV. In general, individuals infected with HCV are often identified because they are found to have elevated liver enzymes on a routine blood test or because a hepatitis C antibody is found to be positive at the time of blood donation. In 1992, a more specific test for anti-HCV became available and eliminated some of the false positive reactions that were previously troublesome. In general, elevated liver enzymes and a positive antibody test for HCV (anti-HCV) means that an individual has chronic hepatitis C. However, the anti-HCV may remain positive for several years after recovery from acute hepatitis C. A small percentage of the patients still may have false positive hepatitis C antibody reactions. In these two cases, liver enzymes are typically normal. It
appears that the formation of antibodies in response to the virus (associated
with immunity in other forms of viral infections) does not apply with
hepatitis C. Researchers believe this is because the virus changes to
new forms of the original virus which caused the body to produce antibodies.
It is estimated that up to 85 percent of the 150,000 people infected
with the hepatitis C virus each year will develop chronic hepatitis.
There are 3.5 million Americans chronically infected with HCV. HCV can be transmitted through blood transfusions. However, all blood is now tested for the presence of this virus by the antibody test. It is estimated that the risk of post-transfusion hepatitis C has been reduced from the 8-10 percent frequency of infection several years ago to less than 0.5 percent. Other individuals who may come in contact with infected blood, instruments, or needles, such as IV drug users, health care workers or laboratory technicians are also at risk of acquiring hepatitis C. Currently, there is no vaccine available to immunize individuals against this virus. The risk for transmitting hepatitis C sexually is unknown. There have been rare, documented cases of people with chronic hepatitis C transmitting the virus to their only, long-term sexual partner. The Center For Disease Control and Prevention (CDC) says that because of the lack of sufficient information those with only one, long-term sexual partner need not change their sexual practices. Many physicians who counsel patients with hepatitis C recommend the same thing to those in a monogamous relationship. CDC
says there is an increased risk of becoming infected with hepatitis
C if you have multiple sex partners. Whether the use of latex condoms
is 100 percent effective in preventing someone from infecting their
sexual partner or becoming infected is uncertain. Specific
information regarding the natural history of hepatitis C is not yet
available. In general, however, chronic hepatitis C appears to be a
slowly progressive disease that may gradually advance over 10-40 years.
There is some evidence that the disease may progress faster when acquired
in middle age or older. In one study, chronic hepatitis by liver biopsy
was identified on the average of ten years following blood transfusions
and cirrhosis on an average of 20 years. It also appears that HCV, like
the hepatitis B virus, is associated with an increased chance of developing
hepatocellular carcinoma, a type of primary liver cancer. Almost all
HCV-related liver cancer occurs with cirrhosis (scarring) of the liver.
The exact magnitude of this risk is unknown but appears to be a late
risk factor occurring on the average of 30 years after the time of infection.
This is more prevalent in the Far East than in the U. S. The drug, interferon alpha-2b, has been approved for the treatment of chronic hepatitis C. Approximately 40 percent of patients treated for six months with interferon will respond, showing major improvement or normalization of liver tests and reduced inflammation on liver biopsy. However, of those who respond to treatment, approximately 60 percent will suffer a relapse during several months after interferon treatment is discontinued. Thus, only 10-15 percent of patients treated with interferon have a sustained, long-lasting response. Patients can be treated a second time and 85 percent of patients will enter a second remission; however, the duration of treatment and dosage required for long-term remission in this group of patients has yet to be determined. In a recent multi-center trial in Europe, 44 percent of the hepatitis C patients on the standard dosage for 18 months had their elevated liver enzymes return to normal. This group was evaluated 19 to 42 months after this initial 18 month therapy and half of them (22 percent) still had normal liver enzymes. The hope is that improvement or normalization of liver tests and reduced inflammation in the liver will slow or interrupt the development of progressive liver disease. However, the true impact of interferon treatment on the long-term course of chronic hepatitis C and survival is unknown. Side
effects caused by interferon therapy are frequent and include "flu-like"
symptoms, depression, headache, and decreased appetite. The "flu-like"
symptoms can be minimized by taking two doses of acetaminophen (e.g.,
Tylenol). In addition, interferon may depress the bone marrow leading
to difficulties with the white blood cells and platelets. Frequent blood
tests are needed to monitor white blood cells, platelets and liver enzymes.
A liver biopsy is typically done prior to treatment to determine the
severity of liver damage and provide confirmation of the underlying
disease. You
should seek referral to a gastroenterologist or liver specialist so
that further testing can be performed to determine the significance
of the reactive antibody and whether or not you have chronic hepatitis
C.  HEPATITIS C TEST RESULTS
American
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