Hepatitis C is an infection caused by a virus that attacks the liver and leads to inflammation. Most people infected with the hepatitis C virus (HCV) have no symptoms. In fact, most people don’t know they have the hepatitis C infection until liver damage shows up, decades later, during routine medical tests.
Hepatitis C is one of several hepatitis viruses and is generally considered to be among the most serious of these viruses. Hepatitis C is passed through contact with contaminated blood — most commonly through needles shared during illegal drug use.
HEPATITIS C CAUSES
Hepatitis C is a liver disease that is caused by infection with the hepatitis C virus, a virus that lives in your liver cells.
HEPATITIS C PATHOPHYSIOLOGY
The cause of hepatitis C, HCV, is a spherical, enveloped, single-stranded RNA virus belonging to the Flaviviridae family and Flavivirus genus. The natural targets of HCV are hepatocytes and, possibly, B lymphocytes. Viral clearance is associated with the development and persistence of strong virus-specific responses by cytotoxic T lymphocytes and helper T cells.
In most infected people, viremia persists and is accompanied by variable degrees of hepatic inflammation and fibrosis. Findings from studies suggest that at least 50% of hepatocytes may be infected with HCV in patients with chronic hepatitis C.
RNA-dependent RNA polymerase, an enzyme critical in HCV replication, lacks proofreading capabilities and generates a large number of mutant viruses known as quasispecies. These represent minor molecular variations with only 1-2% nucleotide heterogeneity. HCV quasispecies pose a major challenge to immune-mediated control of HCV and may explain the variable clinical course and the difficulties in vaccine development.
HEPATITIS C SYMPTOMS
Hepatitis C infection usually causes no symptoms until late in the course of chronic infection. In its earliest stages, beginning about one to three months after exposure to the virus, the following signs and symptoms occur in a small proportion of infected people:
- Nausea or poor appetite
- Stomach pain
- Dark-colored urine
- Yellow discoloration in the skin and eyes (jaundice)
- Muscle and joint pains
Signs and symptoms of chronic infection typically become evident after years and are the result of liver damage caused by the virus. These may initially include the symptoms of acute infection. Then, over time, signs and symptoms may include:
- Bleeding easily
- Bruising easily
- Itchy skin
- Fluid accumulation in your abdomen (ascites)
- Swelling in your legs
- Weight loss
- Confusion, drowsiness and slurred speech (hepatic encephalopathy)
- Spider-like blood vessels on your skin (spider angiomas)
HEPATITIS C DIAGNOSIS
Because many people don’t have symptoms, it’s common for people to have hepatitis C for 15 years or longer before it is diagnosed. Many people don’t find out that they have the virus until they are tested for some other reason, such as when donating blood. Experts recommend that all adults born from 1945 to 1965 should be tested for hepatitis C.4, 5 People in this age group are more likely to have hepatitis Cand not know it.
It is important to be tested for hepatitis C if you:
- Have signs or symptoms of liver disease, such as abnormal livertests.
- Received blood from a donor who was found to have hepatitis C.
- Have ever shared needles while using drugs, even if you only experimented many years ago.
- Are a health care worker who may have been exposed tohepatitis C through a needle stick or other contact with blood or body fluids.
- Have many sex partners or have a sex partner who has a chronic hepatitis C infection.
- Have had your blood filtered by a machine (hemodialysis) because your kidneys cannot filter your blood.
Received blood, blood products, or a solid organ from a donor before 1992. Since 1992, all donated blood and organs are screened for hepatitis C. So it is now rare to get the virus this way.
Received blood-clotting factor concentrates (used to treat blood disorders such as hemophilia) before 1987. In 1987, screening of clotting factor concentrates for hepatitis C became a requirement.
Before you have tests, your doctor will probably talk to you about the pros and cons of testing for hepatitis C so that you understand what having the virus mea
HEPATITIS C TREATMENT
Hepatitis C infection is treated with antiviral medications intended to clear the virus from your body. The goal of treatment is to have no hepatitis C virus detected in your body at least 12 weeks after you complete treatment.
Although medications to treat hepatitis C have been available for decades and have gradually improved with time, they have had serious side effects and required that a person be treated from 24 to 72 weeks. Side effects included depression, flu-like symptoms, and loss of healthy red or white blood cells (anemia or neutropenia). Therefore many people discontinued treatment.
Researchers have recently made significant advances in treatment for hepatitis C, combining new anti-viral medications with existing ones. As a result, people experience better outcomes, fewer side effects and shorter treatment times — some as short as 12 weeks. Regimens may vary depending on the hepatitis C genotype, presence of existing liver damage, other medical conditions and prior treatments, but they’re generally much more effective today than previously.
Due to the pace of research, recommendations for medications and treatment regimens are changing rapidly, and treatment is also quite complex. It is therefore best to discuss your treatment options with a specialist.
Throughout treatment your doctor will monitor your response to medications.
If your liver has been severely damaged, a liver transplant may be an option. During a liver transplant, the surgeon removes your damaged liver and replaces it with a healthy liver. Most transplanted livers come from deceased donors, though a small number come from living donors who donate a portion of their livers.
For people with hepatitis C infection, a liver transplant is not a cure. Treatment with antiviral medications usually continues after a liver transplant, since hepatitis C infection is likely to recur in the new liver.
Although there is no vaccine for hepatitis C, your doctor will likely recommend that you receive vaccines against the hepatitis A and B viruses. These are separate viruses that also can cause liver damage and complicate treatment of hepatitis C.