Infection: Hepatitis C
Infection: Hepatitis C
Definition
Description
Demographics
Causes and Symptoms
Diagnosis
Treatment
Prognosis
Prevention
The Future
For more information
Definition
Hepatitis C infection is an inflammatory disease of the liver caused by HCV. HCV is most commonly transmitted from person to person through contaminated blood.
Description
Hepatitis C is an infection that often goes undetected until it has done significant damage to a patient's liver. The infection has two phases, acute (the first six months) and chronic (after the first six months). A minority of patients clear the virus from their bodies during the acute phase, but 60–85 percent have a chronic hepatitis C infection.
People may have no symptoms of illness during the acute phase of hepatitis C infection and possibly only a mild flu-like syndrome later. Symptoms of severe liver damage, such as nausea, vomiting, collection of fluid in the abdomen, and mental changes, may not develop for ten or twenty years after the initial infection.
Demographics
Hepatitis C is the major source of chronic liver infection in North America. There are approximately 30,000 new infections and 8,000–10,000 deaths each year in the United States. It is estimated that 4 million persons in the United States have been infected by HCV and 2.7 million of these have the chronic form. HCV infection presently accounts for 40 percent of referrals to liver clinics.
HCV is more common among Hispanics and African Americans than among Caucasians, Asian Americans, or Native Americans. Sixty-five percent of persons with HCV infection are between thirty and forty-nine years of age.
People who are at increased risk of HCV include:
- Those who abuse intravenous drugs (60 percent of new cases)
- People who have unprotected sex with a large number of partners
- People who require hemodialysis for kidney disorders
- People who need frequent blood transfusions
- People who are HIV-positive
- Health care workers who may get needle-stick injuries
Causes and Symptoms
Hepatitis C is caused by HCV. It is most often transmitted from one person to another through infected blood or blood products, but can also be (uncommonly) transmitted from mother to child during childbirth or through sexual intercourse. Before 1992, HCV was sometimes transmitted through blood transfusions, hemodialysis, or transplanted organs from infected donors; these are now rare events. In 1992, researchers invented a new test for checking blood products for HCV; as a result, new infections annually in the United States declined from 240,000 in the 1980s to about 20,000–30,000 in 2007. The most common cause of HCV transmission is intravenous drug use; transfusion-related cases of hepatitis C now occur only once in every 2 million transfused units of blood.
Hepatitis C infection is sometimes divided into an early phase called the acute stage and a later phase called the chronic stage. The acute stage begins when the virus enters the body; it lasts for about six months. Antibodies to the virus can usually be detected between three and twelve weeks after infection. About 15–40 percent of people who are infected clear the virus from their bodies during this phase, while the other 60–85 percent go on to develop chronic hepatitis C infection. It is this second group of patients who run the risk of suffering cirrhosis or other forms of liver or kidney damage years later.
Eighty percent of patients infected by HCV in its early stage do not have any symptoms, or have mild and nonspecific symptoms like fatigue. Others have a flu-like syndrome marked by poor appetite or nausea, soreness in the area of the liver, or pains in the joints and muscles. Some may notice that their urine is dark and looks like tea or cola. If chronic HCV infection leads to liver disease ten to twenty years later, the patient may have the following symptoms:
- Severe loss of appetite
- Nausea and vomiting, with blood in the vomit
- Low-grade fever
- Itchy skin
- Jaundice (This is a yellowish discoloration of the whites of the eyes and the skin caused by an increase in the amount of bile pigments from the liver in the patient's blood.)
- Sleep disturbances
- Swelling of the abdomen caused by fluid retention
- Diarrhea
- Difficulty urinating
- Confusion, hallucinations, difficulty concentrating, or other mental disturbances
Diagnosis
Diagnosis of hepatitis C infection is often delayed for years because many patients with chronic hepatitis C infection do not have noticeable or troublesome symptoms until liver damage has already occurred. In some cases a person with chronic hepatitis C infection is detected through routine blood testing for abnormal liver function or because they have a history of intravenous drug abuse or HIV infection. Testing for chronic infection begins with blood tests that indicate the presence of antibodies to HCV. Since antibody tests cannot tell whether the person is currently infected, however, a second blood test that looks for the virus's characteristic genetic material is performed.
An Outbreak in Nebraska
Transmission of hepatitis C virus (HCV) within health care facilities is never supposed to occur. In 2000–2001, however, an outbreak in Nebraska, traced to poor health safeguards at a private cancer clinic, affected almost 100 patients. A physician's wife who began treatment for breast cancer at the clinic in 2001 was surprised to find out in 2002 that she was infected with HCV. Her husband discovered on checking his records that several of his patients were also infected; all were undergoing cancer therapy at the same clinic.
An investigation by the Nebraska Health and Human Services System found that in March 2000 a clinic nurse used a syringe to rinse a known HCV patient's chemotherapy port with saline solution then used the same syringe to draw more saline from a large common container, thus transferring HCV from the infected port into the container. The virus was transmitted to other patients via the saline solution and repeated use of contaminated syringes.
Between March 2000 and June 2001, when the nurse left the clinic, 99 of the clinic's 857 patients were infected with HCV. As of 2008, at least one had died. Disturbingly, the Nebraska case is not alone; the Centers for Disease Control and Prevention (CDC) recorded at least 32 outbreaks of HCV in the United States since 1999. In March–May of 2008, 84 patients contracted HCV at an endoscopy center in Las Vegas, Nevada—again as the result of reusing contaminated syringes.
If the results are positive for both tests, the doctor will order a third blood test that determines the virus's specific genotype or genetic makeup. There are six known genotypes of HCV as of 2008, and knowing which type is involved helps to guide the patient's treatment.
To determine the extent of damage to the patient's liver, the doctor may order a liver biopsy. In this procedure, a needle is inserted into the patient's liver through the abdomen in order to remove a small sample of tissue for analysis.
Treatment
Not all patients with HCV require therapy, but if treatment is needed, the first line of treatment comprises two medications known as Inter-feron, a drug that resembles some of the proteins that the body makes naturally to fight viruses, and Virazole, which is an antiviral drug. The combination of these drugs works better than Interferon alone. Inter-feron is usually given as a shot once a week and Ribavirin is taken as a pill twice a day. The length of treatment depends on the genotype of HCV; patients with genotype 2 or 3 are treated for twenty-four weeks whereas patients with genotype 1 or 4 must undergo forty-eight weeks of treatment. The cure rates for genotypes 1 and 3 are about 75 percent; the cure rate for genotype 1 is 50 percent; and for genotype 4 it is 65 percent. Unfortunately, Interferon and Ribavirin produce unpleasant side effects for patients that range from depression and irritability to weight loss, nausea, and muscle pains. In addition to side effects, Ribavirin cannot be given at all to pregnant women because it can harm the unborn child.
The only treatment for cirrhosis or severe liver disease is liver transplantation. The problem, however, is that there are many more patients waiting for donated livers than there are suitable organs available. In addition, liver transplantation does not cure hepatitis C infection; most people who receive transplanted livers will develop a recurrence of the virus. The effectiveness of medication treatment of hepatitis C following a liver transplant is unclear.
Patients with chronic hepatitis C should stop drinking alcohol, as it can speed up the rate of liver damage. They should also be vaccinated against hepatitis A and hepatitis B.
Prognosis
According to the CDC, between 75 and 85 percent of people infected with HCV will develop chronic hepatitis C infection. Twenty percent of these chronically infected persons will develop cirrhosis of the liver within twenty years of infection; 1–5 percent of chronically infected people will eventually die of liver disease.
Women with chronic hepatitis C have better outcomes than men, and patients infected at younger ages have better outcomes than those infected in middle age. The reason for these differences is not clear.
Prevention
There is no vaccine that can prevent HCV. Prevention depends on careful observation of good health practices in hospitals and clinics and on individual lifestyle changes. The CDC recommends the following ways that individuals can lower their risk of getting hepatitis C:
- Do not use intravenous drugs. People who cannot quit should never share their needles, syringes, water, or other materials used to inject drugs. They should also get vaccinated against hepatitis A and hepatitis B.
- Do not share personal items (razors, toothbrushes, etc.) that might have blood on them.
- Avoid getting tattoos or body piercing. People who do get a tattoo, however, should at least make sure that the operator who performs the tattoo is using proper sterile procedure.
- Use latex condoms when having sex. Although it is rare for HCV to be transmitted through sexual intercourse, it can happen.
- People who discover that they are infected with HCV should not donate blood, organs, or tissues.
WORDS TO KNOW
Chronic: Recurrent or long-term.
Cirrhosis: Liver damage most commonly caused by alcoholism or hepatitis C.
Genotype: The genetic makeup of a cell or organism.
Hepatitis: Inflammation of the liver. It can be caused by toxic substances or alcohol as well as infections.
Jaundice: A yellowish discoloration of the skin and whites of the eyes caused by increased levels of bile pigments from the liver in the patient'sblood.
The Future
Researchers expect the number of people who die from hepatitis C in the United States to increase in the following years. One researcher found that the number of deaths due to HCV-related complications rose from
fewer than 10,000 in 1992 to almost 15,000 in 1999. This number is expected to rise in the years ahead because of the growing numbers of people with HIV and other chronic infections. These infections increase a person's risk of developing severe liver disease if they do become infected with HCV.
Researchers are continuing to work on an effective vaccine against HCV and more effective medications with fewer side effects for treating the chronic form of the disease.
SEE ALSO Hepatitis A; Hepatitis B
For more information
BOOKS
Fabry, Stephen, and R. Anand Narasimhan. 100 Questions and Answers about Hepatitis C: A Lahey Clinic Guide. Sudbury, MA: Jones and Bartlett Publishers, 2006.
McKnight, Evelyn V. A Never Event: The Story of the Largest American Outbreak of Hepatitis C in History. New York: Arbor Books, 2008.
PERIODICALS
Associated Press. “CDC: Syringe Reuse Linked to Hepatitis C Outbreak.” Las Vegas Sun, May 19, 2008. Available online at http://www.lasvegassun.com/news/2008/may/19/cdc-syringe-reuse-linked-to-hepatitis-c-outbreak/ (accessed June 11, 2008).
Macedo de Oliveira, Alexandre, Kathryn White, Dennis Leschincky, et al. “An Outbreak of Hepatitis C Infections among Outpatients at a Hematology/Oncology Clinic.” Annals of Internal Medicine 142 (June 7, 2005): 898–902. Available online at http://www.largestamericanoutbreak.com/ (accessed June 11, 2008). Article about the Nebraska hepatitis C outbreak of 2001, the largest to date in North America.
McKeever, Kevin. “Sharp Rise in Hepatitis C-Related Deaths.” HealthDay, March 27, 2008. Available online at http://www.nlm.nih.gov/medlineplus/news/fullstory_62713.html (accessed June 11, 2008).
WEB SITES
Centers for Disease Control and Prevention (CDC). Viral Hepatitis C: Fact Sheet. Available online at http://www.cdc.gov/ncidod/diseases/hepatitis/c/fact.htm (updated March 6, 2008; accessed June 11, 2008).
Mayo Clinic. Hepatitis C. Available online at http://www.mayoclinic.com/health/hepatitis-c/DS00097 (updated September 14, 2007; accessed June 11, 2008).
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Viral Hepatitis: A through E and Beyond. Available online at http://www.digestive.niddk.nih.gov/ddiseases/pubs/viralhepatitis/ (updated February 2008; accessed June 11, 2008).
National Library of Medicine (NLM). Hepatitis C. Available online at http://www.nlm.nih.gov/medlineplus/tutorials/hepatitisc/htm/index.htm (accessed June 11, 2008). Online tutorial with voiceover; viewers have the option of a self-playing version, an interactive version with questions, or a text version.
Nemours Foundation. Hepatitis. Available online at http://www.kidshealth.org/parent/infections/bacterial_viral/hepatitis.html (updated February 2006; accessed June 11, 2008).