Hepatitis C

Hepatitis C

Medical Author: Tse-Ling Fong, M.D.
Medical Editor: Leslie J. Schoenfield, M.D., Ph.D.

• What is the scope of the hepatitis C problem?
• What is the nature (biology) of the hepatitis C virus (HCV)?
• How does liver damage occur in hepatitis C infection?
• How is hepatitis C virus spread and how can transmission be prevented?
• What are the symptoms of hepatitis C infection?
• What conditions outside the liver are associated with hepatitis C?
• What is the usual progression of chronic infection with hepatitis C virus?
• Who is at high risk and should be tested for hepatitis C infection?
• What are the diagnostic tests for hepatitis C virus and how are they used to diagnose hepatitis C virus infection?
  • What about screening tests?
  • What are molecular tests for hepatitis C virus?
  • What is the role of the qualitative molecular tests?
  • How are the results of the hepatitis C virus tests interpreted?
  • What is the role of quantitative hepatitis C virus RNA testing?
  • What tests identify the virus genotypes?
• What is the role of a liver biopsy in the management of chronic hepatitis C?
• Who should receive antiviral therapy for hepatitis C virus?
• What are the different patterns of response to antiviral treatment?
• What are the goals of therapy for hepatitis C virus?
• What are the therapy options for previously untreated patients with chronic hepatitis C?
  • Conventional interferon alone (monotherapy)
  • Combined conventional interferon and ribavirin
  • Pegylated interferon monotherapy
  • Combined pegylated interferon and ribavirin
• How are relapsers and nonresponders treated?
• Should individuals with acute hepatitis C be treated?
• What are the side effects of treatment for hepatitis C virus?
• What about liver transplantation for hepatitis C?
• What is the current research and what is in the future for hepatitis C?
• Hepatitis C At A Glance
• Related Hepatitis articles:
  Hepatitis - on WebMD

What is the scope of the hepatitis C problem?

The hepatitis C virus (HCV) is one of the most significant health problems affecting the liver. More than 4 million Americans (1.3% of the U.S. population) and 170 million individuals in the world (3% worldwide) are infected with hepatitis C virus. The prevalence (number of cases in a population at a specific time) of hepatitis C virus infections varies in different parts of the world. For example, the prevalence of hepatitis C virus in Scandinavia is less than 0.5% of the population, whereas the prevalence in Egypt is over 20%. In the U.S. and Western Europe, the complications of hepatitis C virus chronic hepatitis and cirrhosis are the most common reasons for liver transplantation.

One of the major problems with hepatitis C virus infections is that 85% of individuals initially infected with this virus will become chronically infected, usually for decades. The other 15% of hepatitis C virus infected individuals simply have an acute infection; that is, one that resolves spontaneously in a few weeks or months. The propensity of hepatitis C virus to cause chronic infection is explained by the extraordinary ability of this virus (in contrast to most other viruses, including hepatitis A) to avoid destruction by the body's immune defense system. (The immune system includes antibodies and specialized white blood cells, called lymphocytes).

Once established, chronic hepatitis C virus infection causes an inflammation of the liver called chronic hepatitis. This condition can progress to scarring of the liver, called fibrosis, or more advanced scarring, called cirrhosis. Some patients with cirrhosis will go on to develop liver failure or the complications of cirrhosis, including liver cancer.

In the U.S., the number of new cases of hepatitis C has declined over the last 10 years from a peak of some 200,000 annually to about 28,000 in 1999. This striking reduction is the result of a drop in the number of cases of acute hepatitis C among intravenous drug users. Perhaps this decrease among the drug users is due to changes in their practices brought on by their awareness of HIV infection. Furthermore, sensitive blood tests for the detection of hepatitis C virus became available to screen the blood supply and individuals at high risk for hepatitis C virus.

Indeed, with blood being routinely screened for hepatitis C virus, the risk of a single unit of blood transmitting hepatitis C today is less than 1 in 100,000. Still, because of the many individuals who became infected 10 to 20 years ago, the number of deaths (or the need for liver transplantation) due to the complications of chronic hepatitis C virus liver disease is expected to triple within the next decade or two. On the other hand, in recent years, our understanding of the hepatitis C virus and its management has increased substantially.

Source: MedicineNet.com
http://www.medicinenet.com/hepatitis_c/article.htm