Introduction
Hepatitis is the inflammation of the liver that causes both soreness and swelling. Chronic hepatitis can lead to fibrosis (scarring) and cirrhosis (fibrosis plus abnormal regeneration of liver cells) or even to liver carcinoma. Hepatitis is generally caused by viruses though there are other factors such as toxic chemicals, alcohol consumption, parasites and bacteria, and certain drugs that can cause hepatitis. Symptoms of hepatitis are nausea, fever, weakness, loss of appetite, sudden distaste for tobacco smoking, and jaundice (CE, 2004). There are many kinds of hepatitis named hepatitis A through E. Hepatitis C, formerly called non-A, non-B hepatitis, is transmitted through blood although in many cases there is no proven cause (CE, 2004). It is the most common form of chronic liver disease in the United States. Many of those infected have no symptoms but become carriers, and the virus may eventually cause liver damage. Blood banks conduct tests for hepatitis C as a matter of routine. The virus that causes Hepatitis C is HCV. It is a positive, single-stranded RNA virus in the Flaviviridae family (Worman, 2002).
Prevalence
Approximately 170,000,000 people worldwide and 4,000,000 in the United States are infected with HCV (Worman, 2002). Chronic infection is found in 55%-85% of infected persons; chronic liver disease happens 70% of chronically infected persons and mortality rate is around 1%-5% deaths from chronic liver disease (CDC, 2005). However, latest statistics show that there has been a decline in hepatitis C and new infections per year has declined from an average of 240,000 in the 1980s to about 26,000 in 2004 (CDC, 2005). Illegal injection drug use and alcohol abuse can multiply the possibilities of having chronic hepatitis C(Bean and Nemitz, 2004). There is also a decline in cases of hepatitis C caused by transfusion due to efficient blood screening practices. The CDE reports that approximately 4.1 million (1.6%) Americans have been infected with HCV, of whom 3.2 million are chronically infected (CDC, 2005).
Prognosis
About 85% of individuals acutely infected with HCV become chronically infected. Hence, HCV is a major cause of chronic hepatitis. Once chronically infected, the virus cannot be eradicated without treatment. Some patients do not develop any complication while some patients develop chronic hepatitis which can later become cirrhosis. About 20% of individuals with hepatitis C who develop cirrhosis are likely to develop end-stage liver disease (Worman, 2002). Cirrhosis caused by hepatitis C is presently the leading indication for orthotopic liver transplantation in the United States. Individuals with cirrhosis from hepatitis C are also at an increased risk of developing hepatocellular carcinoma (primary liver cancer). In general, younger patients with evidence of active inflammation on liver biopsy and without advanced cirrhosis have excellent prognosis with treatment (Worman, 2002). A major problem in discussing prognosis in patients with chronic hepatitis C is that it is difficult to predict who will have a relatively mild course and who will go on to develop cirrhosis or cancer. However, alcohol abuse can increase chances of developing cirrhosis (Bean, 2004).
Diagnosis
The diagnosis of chronic hepatitis C is made by history, serological testing and liver biopsy. Most patients with chronic hepatitis C will be asymptomatic or have non-specific symptoms such as fatigue. In some individuals, the diagnosis will be suspected from the results of blood tests obtained for other reason (usually elevations in the serum alanine and aspartate aminotransferase activities) (Worman, 2002). Generally people with symptoms of chronic liver disease and those who have a history of drug abuse or alcohol abuse need to be tested for the presence of serum antibodies against HCV. If it is present it suggests the diagnosis of chronic hepatitis C. In order to confirm the diagnosis, tests for HCV RNA in blood should be carried out in persons with anti-HCV antibodies. After making the diagnosis, it is best to do a liver biopsy to assess the degree of liver inflammation and fibrosis and the presence or absence of cirrhosis (Worman, 2002).
Treatment
Treatment of chronic hepatitis C is presently based on the use of interferon-alpha. Interferon-alpha is a protein that is given by injection, usually three times a week. The addition of ribivirin, a non-specific, orally administered anti-viral agent, improves the efficacy of interferon-alpha. Although interferon-alpha with or without ribivirin works for some patients with hepatitis C, most do not achieve a “sustained response” of undetectable virus in blood 6 months after stopping therapy. The next drug available for the treatment of chronic hepatitis C is peginterferon-alpha (sometimes called “pegylated interferon”). The active agent in peginterferon-alpha is the same old interferon-alpha (Worman, 2001). It has demonstrated enhanced compliance and clinically superior anti-viral activity. Currently, combination therapy with peginterferon-alpha-2a (40kD) and oral ribavirin is poised to become a valuable first-line treatment option in chronic hepatitis C (Keating and Curran, 2003). In addition to PEG-Intron, there are three more interferon products approved by the FDA: Intron A, Roferon-A, and Infergen. These three products are injected three times a week; PEG-Intron is injected once a week (Bren, 2001). Therapeutic vaccines are also being developed to enhance the immune response against the hepatitis C virus. A therapeutic vaccine is administered to already-infected individuals to stimulate the immune system to fight the infection (Worman, 2001). Though there is no vaccine to prevent hepatitis C, but there are vaccines for hepatitis A and B. The CDC recommends these vaccines, particularly the hepatitis A vaccine, for HCV-positive individuals. Becoming infected with hepatitis A virus can be dangerous for someone with HCV infection.
Bibliography
- Worman, J. Howard (2002). Hepatitis C.
- Columbia Encyclopedia. Hepatitis. 2004. Sixth Edition
- CDE (2005). Hepatitis C Fact Sheet. Web.
- Worman, J. Howard (2001). New and Future Treatments for Chronic Hepatitis C.
- Keating and Curran (2003). Peginterferon-alpha-2a (40kD) plus ribavirin: a review of its use in the management of chronic hepatitis C. Drugs. 2003; 63(7):701-30. Web.
- Bean and Nemitz (2004). Drug Treatment: What Works? Routledge, New York. 2004
- Bren, Linda (2001). Hepatitis C. FDA Consumer, Volume 35, Web.