Understanding Hepatitis C
by Kathryn McParlane, CRNP
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John is a 38 year old attorney married 5 years with 2 young children. He recently decided to apply for more life insurance to protect his growing family. He was surprised when the insurance agent called and told him that he could not give him a policy due to a "liver problem" found in his blood tests. This was a surprise to John who felt perfectly well and only had an occasional beer. He saw his family doctor who did some additional blood work and referred him to our practice for treatment of Hepatitis C. He had never used drugs or needles but did relate that many years ago while in college on Spring Break he got a tattoo. Further tests confirmed significant liver damage from Hepatitis C virus infection and he began a course of therapy which is still underway.
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What does the liver do?
First, a few words about the liver... The liver is a very important organ that is also part of the digestive system. Located under the right rib cage, it weighs about 3 pounds and is the second largest organ in the body after the skin (yes, the skin is the largest organ in the body). The liver is a complex organ that functions like a "chemical factory." It processes important body substances and has many vital duties such as:
1) Storing vitamins, iron, and other minerals
2) Producing bile to help digest food
3) Metabolizing fat, carbohydrates, and proteins
4) Cleaning and purifying the blood
5) Changing blood sugar from glucose (the body's major fuel) to glycogen (the body's storage form)
6) Regulating cholesterol and hormones
7) Producing clotting factors to help stop bleeding from an injury
What is Hepatitis?
Hepatitis is inflammation of the liver. There are many causes of Hepatitis including infection caused by a virus. Viruses are the smallest forms of life and are visible only under the strongest microscopes. There are five viruses (A, B, C, D, and E) that are able to infect the liver. Hepatitis C virus (HCV) is the most common and one of the smallest. If you could put 500,000 Hepatitis C viruses end to end, they would only be one inch long.
How common is Hepatitis C?
HCV is a serious global health problem which has infected an estimated 170 million people, or 3% of the world's population. An additional 3 to 4 million people worldwide are newly infected each year. There are over 4.5 million Americans infected; almost 2% of the U.S. population. Current conservative estimates add about 35,000 new HCV infections annually in the U.S. Few people are aware of this disease. More individuals are infected with HCV than HIV/AIDS. This makes HCV one of the greatest public health threats of this century.
How does Hepatitis affect the liver?
Unlike other living organisms, a virus cannot reproduce itself. Reproduction is accomplished when the virus invades other cells within the body. The HCV virus travels through the bloodstream ultimately invading liver cells. Once the virus invades the liver cell, it reproduces quickly. This produces thousands of new virus particles within that cell which eventually cause the invaded cell to burst, thus spreading more of the virus to the other liver cells.
What are the symptoms?
The problem with HCV is that most people do not have symptoms when they are initially infected - nausea, vomiting, loss of appetite, vague stomach pain, diarrhea, and jaundice (yellow skin) - that are seen earlier with other forms of Hepatitis. If symptoms do occur, they are usually mild and diagnosed as a mild case of the "flu" that comes and goes.
The virus can lie in ambush in the system for decades and then, when symptoms do occur, they are very vague and nonspecific. Most individuals are surprised to learn of their infection when they apply for health insurance, have routine blood tests, or are told they cannot donate blood.
Hepatitis C is a clever virus
When someone is initially infected, it is called Acute Hepatitis C. This acute phase can last up to 6 months. During this time the liver becomes more and more inflamed as the body's immune system attempts to fight off the virus. Most people have very few symptoms in this phase and aren't aware that they have been infected. In only about 15% of people with Acute HCV, the immune system is able to successfully fight off the virus and the inflammation of the liver goes away.
However, HCV is a very clever type of virus which can outmaneuver the body's immune system by mutating, or rapidly changing it's form. Like wearing a disguise, each change makes the virus temporarily invisible to the body's defenses. In most individuals, HCV evolves faster than the immune system can respond. The virus makes itself at home in the liver, and the infection is never completely cleared. That is why the HCV becomes permanent, or chronic, in about 85% of cases. This is different than other types of viral infection, (such as measles, mumps, and Hepatitis A) where the acute illness may last several months, after which the virus is cleared from the body completely.
Chronic Hepatitis C is diagnosed when the virus stays in the body longer than 6 months. When this stage of the infection is reached, the inflammation of the liver doesn't go away. Most infected people feel well for many years, but over time, many healthy liver cells are killed and replaced by non-functioning scar tissue. When enough scar tissue accumulates, the liver ceases to function properly. This is known as cirrhosis of the liver, and occurs in about 20% of those with Chronic HCV. This process is very slow, averaging about 20 years from initial infection to significant liver disease. In fact, chronic HCV is now the most common reason for liver transplant in the United States.
How are people infected with Hepatitis C?
HCV is a blood-borne virus that was discovered in 1989. Prior to this, it was known as "non-A, non-B" Hepatitis. A blood-borne virus is transmitted through an infected person's blood. Almost any direct or indirect exposure to infected blood can transmit the virus.
Previously, one of the most common ways of becoming infected was from blood transfusions and organ donation. This type of transmission has been virtually eliminated since 1992 with the introduction of a very sensitive blood test for HCV antibodies done prior to all donations.
The most common risk is still the sharing of contaminated needles by intravenous (IV) drug users. About 10% of people with HCV don't know how they were infected.
What can be done to prevent spreading this disease?
People who have HCV should always be aware that their blood - and possibly other body fluids - are potentially contagious for the rest of their life. They are given the following guidelines:
Do not share personal hygiene products such as nail clippers, earrings, toothbrushes and razors.
Do not share needles or the apparatus used to snort cocaine and other drugs.
Use bandages to cover open wounds.
Carefully dispose of items that may contain the blood such as tampons or soiled adhesive bandages.
Inform medical and dental providers of the infection, as well as the manicurist, and tattoo artist, so that proper precautions can be taken during procedures at these offices or other places of business.
You will never be able to donate blood.
Casual contact such as hugging, shaking hands, preparing food, and swimming do not spread HCV.
While there are vaccines to protect the public from Hepatitis A and B, there is currently no vaccine for HCV. Because of the viruses ability to mutate frequently, it is unlikely that a vaccine will be available in the near future.
What about sex?
It is generally accepted that the HCV virus is not transmitted efficiently through sexual intercourse. The transmission rate in a monogamous relationship is less than 3%. Consequently, the Center for Disease Control does not recommend changing sexual habits for those couples who have been in a long-term relationship. Spouses should be tested. Each couple will need to decide what is best for them. For those with multiple sex partners, the transmission rate is considered to be higher. It is generally recommended that all people with multiple sex partners should use condoms, not only as a precaution against HCV, but also to reduce the risk of infection of other sexually transmitted diseases.
The Role of Genotyping
Prior to initiating treatment a blood test will be needed to determine your genotype. Genotype is the genetic make-up of the virus. The virus can mutate or change its genetic makeup. By varying its structure, it has evolved into six known genotypes. Determining the genotype helps the doctor determine the duration of therapy and projected response. Genotypes 1a and 1b are the most common in the U.S., accounting for more than 75 percent of all infections. For these genotypes, the hardest to treat, the recommended length of treatment is 48 weeks. For those with genotype 1, the Sustained Virologic Response, (SVR), for combination therapy with Interferon/Ribavirin is 33%. The response rate is now 50% with Pegylated interferon/Ribavirin (preliminary data). Genotype 2 and 3 are present in approximately 20 percent of patients. These genotypes are easier to treat and respond to a recommended treatment period of 24 weeks, with an anticipated SVR of 60% with combined Interferon/Ribavirin and experts predict possible 90 to 100% SVR with combined Pegylated Interferon/Ribavirin though data still very preliminary and incomplete.
How is Hepatitis C treated?
No specific diet has been shown to be helpful, but any and all alcohol use must be stopped. Studies have shown that alcohol enables the virus to multiply faster, causing more inflammation to the liver. In addition, alcohol users are less likely to respond to drug treatment for HCV. In other words, people with HCV who regularly ingest alcohol have a much greater chance of developing cirrhosis or liver failure. Think of the virus as a fire in the liver, and alcohol as gasoline - not a safe combination.
Current treatment for HCV is a combination of two medications. Interferon injections, and Ribavirin pills:
Interferon is a protein that is produced by our immune system to fight infection. A synthetic reproduction of Interferon is injected into the patient to treat HCV. It works by strengthening the body's immune system and preventing the virus from infecting healthy cells. It can't be given orally because digestive enzymes would destroy it. There are different forms of Interferon, just as there are different forms of pain relievers such as aspirin or ibuprofen. The most commonly used types of Interferon are the newer forms which have been "pegylated," that is, attaching a molecule called polyethylene glycol (PEG) to Interferon. This slows the breakdown of Interferon in our body. As a result, the patient only needs to receive an injection once a week. Prior to this development, the injection had to be administered 3 times a week. Two companies produce Interferon, Roche Pharmaceuticals, and Schering Pharmaceuticals.
The other drug treatment used is Ribavirin tablets. Produced by Roche Pharmaceuticals and Schering Pharmaceuticals. Ribavirin is in a class of drugs called nucleoside analogs. Nucleoside analogs help to prevent viruses from multiplying. Ribavirin cannot fight the viruses alone, but studies have shown it helps the Interferon work more efficiently.
Treatment side effects
Side effects of these medications are common and may preclude treatment in some patients. Interferon often makes people feel as if they had a lingering case of the flu with accompanying fever, chills, loss of appetite, joint pain and muscle aches. These side effects lessen as the body becomes accustomed to the extra interferon. Other more serious side effects can occur, including new or worsening mental health problems such as depression. Ribavirin can cause anemia, so blood work will be done frequently. Ribavirin can cause serious birth defects, therefore extreme care must be taken to avoid pregnancy during treatment, and 6 months after treatment.
How effective is treatment?
The goal of treatment is to eradicate the virus from the body and prevent progression of liver disease. Treatment is considered successful if there is no measurable amount of the virus in the blood 6 months after treatment. This is known as a sustained virologic response (SVR). Health care professionals do not use the word "cure" because small amounts of the virus may remain in the body and it is possible that the infection could return. However, if the virus is not detectable in the blood 6 months after treatment, the chances are excellent that the individual will not have measurable virus in their blood for many years to come. There is about a 3-5% chance of the virus coming back, unless reinfected.
There are currently six different strains, or genotypes, of HCV worldwide aptly named type 1 through 6. Genotype 1 is the most common in the U.S., accounting for approximately 75% of all infections. Unfortunately, it is the most difficult to treat; the length of treatment is 48 weeks. Genotype 2 and 3 are present in approximately 20% of infections. These genotypes are easier to treat; treatment lasts for 24 weeks.
With current therapy, the success rate with genotype 1 is about 50%. With genotype 2 and 3, it is around 80%. Realizing HCV could become a serious epidemic, new treatments for Hepatitis C are under development.
Hepatitis C Risk Test
Now that you have some information about HCV, take a few minutes to answer the following questions:
- Have you had a blood transfusion or organ transplant before 1992?
- Have you undergone hemodialysis (treatment with a kidney machine)?
- Have you had your ears or other body part pierced with equipment that may have been contaminated?
- Have you ever had contact with blood in the workplace or military?
- Have you obtained a tattoo using a needle or ink that may have been contaminated?
- Have you ever tried IV drugs?
- Have you snorted cocaine or other drugs from a shared apparatus?
- Have you shared a toothbrush, razor, nail clippers, earrings, or belly rings with someone who has HCV?
- Do you, or have you had unprotected sex with multiple partners?
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If you answer yes to one or more of these questions, you should contact your doctor so that you can have a simple blood test to determine if you have been infected.
Cirrhosis of the Liver |
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This is a normal healthy liver that has been removed during an autopsy. The surface is uniform and smooth. Aging itself does not really affect the appearance of the liver, so it should look like this even as a person ages.
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This liver was removed from a patient who died of cirrhosis of the liver. Note the darkened appearance and many nodules of scar tissue that have developed, deforming the appearance of the liver. When the liver cells turn into scar tissue, they no longer can function normally, and liver failure develops.
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Useful Digestive Links
gihealth.com
NDDIC
Functional GI Disorders
Crohns and Colitis
Liver Foundation
Celiac Society
Ostomy Association
Amer Gastro Assoc
Gastro Endoscopy
Amer Cancer Society
OncoLink
Tufts Nutrition
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