Hepatitis (hep-a-TY-tis) is inflammation * of the liver, an abnormal condition that harms liver cells. It usually is caused by the hepatitis A, B, or C virus and may be acute * or chronic * , mild or extremely serious. Hepatitis also can be caused by other germs, by toxic chemicals, or by certain medications.
KEYWORDS
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Cirrhosis
Hepatic necrosis
Inflammation
Jaundice
Liver transplant
What Is Hepatitis?
The liver, a red-brown, wedge-shaped organ in the upper abdomen, is the largest internal organ in the body and performs the widest range of jobs. It gets rid of harmful substances in food, disposes of old blood cells, helps digest fat, produces chemicals to make the blood clot, and makes sure the blood carries the right balance of fat, sugar, and amino (a-ME-no) acids (the building blocks of proteins) to all the cells of the body.
Complex as it is, the liver is also open to a wide range of problems. Many of these fall under the heading "hepatitis," a general term that means the liver is experiencing inflammation.
* inflammation (in-fla-MAY-shun) is the body's reaction to infection or irritation.
* acute means sudden, short, and severe,
* chronic (KRON-ik) means continuing for a long period of time.
* immune system is the body system that fights disease.
Hepatitis can be caused by many things: excessive drinking of alcohol, overdoses or side effects of medication, inhaling of toxic chemicals, or problems with a person's immune system * . It can also result from infection with a range of microbes.
Most hepatitis is caused by infection with a hepatitis virus * , usually the hepatitis A, B, or C virus. Each one can cause acute viral hepatitis, an inflammation of the liver that usually lasts 4 to 6 weeks. Typically, people who have acute viral hepatitis feel exhausted, and their skin and the whites of their eyes take on a yellowish tint, a condition called jaundice (JAWN-dis). In rare cases, acute viral hepatitis can develop into a life-threatening illness called fulminant * hepatitis. But usually it is milder, and the person recovers without needing special care. Often, viral hepatitis causes no symptoms at all.
Hepatitis B and C, however, can do long-term damage as well. About 75 to 85 percent of people infected with hepatitis C (and 5 to 10 percent of those infected with hepatitis B) cannot fight off the virus. They become infected chronically, meaning the virus remains active in their body for more than 6 months. In most cases, the infection lasts for decades.
Because the liver is large and resilient, it usually keeps working well despite the virus. In fact, most people with chronic hepatitis live a normal life span and do not even realize that they have the infection. But after 10, 20, 30, or more years, some people with chronic infections eventually will have serious liver damage, such as cirrhosis (si-RO-sis), or scarring of the liver. These unlucky people also have a much greater than normal risk of developing a kind of liver cancer * called hepatocellular carcinoma (hep-a-to-SEL-yoo-lar kar-si-NO-ma). Cirrhosis and liver cancer are both serious, often fatal illnesses.
In the United States, hepatitis C is second only to alcohol abuse as a cause of liver damage and is the leading reason people get liver transplants * . Hepatitis C is less likely to cause a noticeable acute illness than hepatitis B, so that most people do not know they have it, but it is more likely to lead to a chronic infection.
Worldwide, hepatitis C is believed to infect 170 million people, and health officials fear it will cause major public health problems in the future. Yet HCV, as it is called, is not as well-known as many rarer diseases. The virus was not identified until 1988, and much remains to be learned about how it behaves. One of its apparent effects is to make alcohol more toxic to the liver: many people with liver damage from alcohol turn out to have hepatitis C as well.
* virus (VY-rus) is a tiny infectious agent that lacks an independent metabolism (muh-TAB-o-liz-um) and can only reproduce within the cells it infects.
* fulminant (FUL-mi-nant) means occurring suddenly and with great severity.
* cancer is an uncontrolled growth of cells or tissue, the natural (untreated) course of which can be fatal.
* transplants (TRANS-plantz) are organs or tissues from another body used to replace a poorly functioning organ or tissue.
In addition to hepatitis A, B, and C, scientists have identified three less-common hepatitis viruses:
Hepatitis D acts as hepatitis B's sidekick. It is found only in people who already have hepatitis B, and it makes their illness worse.
Hepatitis E occurs only in the developing world. It resembles hepatitis A in that it causes only a short-term illness, but it can be more dangerous, especially to pregnant women. It is usually spread through water that has been contaminated by sewage, often after flooding.
Hepatitis G virus was identified in 1996, but it is not clear that it causes any illness.
There is some evidence for a hepatitis F virus as well, but scientists are not sure.
Hepatitis A: How Does It Spread?
Every now and then, local news reports will tell of an outbreak of hepatitis. Often, the announcers will say that people who ate in a certain restaurant or attended a certain nursery school in the last few weeks should consult their doctor to see about preventing infection.
Hepatitis A is the virus that causes that kind of outbreak. Sometimes called infectious hepatitis, it is highly contagious * , but it almost never does permanent damage. In the United States, hepatitis A most commonly is spread in day care centers to young children and their parents. It spreads by what doctors call the "fecal-oral route." Virus in the feces (stool) of an infected person somehow gets into the mouth of someone else. This can happen if people fail to wash their hands after changing a diaper or using the toilet and then go on to prepare or serve food. Or one toddler may handle another's cup or pacifier. In addition, sewage that is not treated properly can contaminate water supplies. Shellfish from contaminated waters can spread the virus if eaten raw or undercooked.
Once people have recovered from hepatitis A, it is over. They are not "carriers" of the virus and cannot infect anyone else.
Hepatitis A: How Is It Prevented?
Good hygiene, including washing hands after using the toilet and before handling food, can prevent hepatitis A.
Vaccination * against hepatitis A also is available. It is recommended for children and adults traveling to developing countries, for children in communities with high rates of hepatitis A, such as among people of Native American ancestry, and for children who live in states with above-average levels of the disease.
Once people have been exposed to the virus, infection often can be prevented by an injection of immune globulin (GLOB-yoo-lin), a substance that helps the immune system. But the globulin must be given within two weeks of exposure to the virus.
Hepatitis B and C: How Do They Spread?
Hepatitis B and C are spread chiefly by contact with an infected person's blood. People with chronic hepatitis B and C are "carriers," meaning their blood can transmit the virus to others even if they have no symptoms of illness.
In the United States, these viruses spread most commonly when intravenous (in-tra-VEE-nus) drug users share needles. About 90 percent of people who inject illegal drugs are believed to be infected with hepatitis C, for instance.
Accidental needle sticks, a risk to health care workers, can also spread these viruses. So can organ transplants, tattooing, body piercing, and sharing razors, toothbrushes, or other objects that may have small amounts of blood on them.
* contagious (kon-TAY-jes) means able to be transmitted from one person to another.
* vaccination (vak-si-NAY-shun) is taking into the body a killed or weakened germ, or a protein made from such a microbe, in order to prevent, lessen, or treat a disease.
Transfusions (trans-FEW-zhunz) of infected blood used to be the biggest source of infection. People with hemophilia (he-mo-FIL-e-a), a blood-clotting problem, were especially likely to be infected when they got blood products drawn from large numbers of donors. Today, however, donors and blood in the United States are screened for both hepatitis B and C, and the risk of getting them from a transfusion is extremely low. But anyone who got a transfusion before July 1992 should be tested for hepatitis C.
Hepatitis B is more contagious than hepatitis C. It is also more contagious than HIV, the virus that causes AIDS * . Hepatitis B spreads readily through sexual contact. Women and men, especially homosexual men, who have sex with many partners are at increased risk.
Hepatitis C is less likely to spread through sexual contact, although it is not clear exactly how easily it spreads this way. In several studies of marriages where one partner is infected with hepatitis C, the other partner does not seem to have an increased risk of getting it. But people who have sex with many partners seem to run a greater risk of infection. Women appear more likely to get hepatitis C from men than vice versa.
Hepatitis B, and more rarely hepatitis C, can also spread from infected mothers to newborns.
Finally, in more than 10 percent of hepatitis C cases, there is no obvious source of infection. It is possible that some means of transmission has yet to be identified.
Neither hepatitis B nor C, however, are known to spread through air, water, or food. A person cannot catch them by being near infected people or by hugging, working, going to school, or swimming with infected people.
How Is Hepatitis B Prevented?
A vaccine can prevent hepatitis B. Since 1991, U.S. health officials have recommended that all newborns receive the necessary three injections. All children ages 11 or 12 should be vaccinated if they did not get the shots as babies. This, officials hope, may virtually eliminate the disease in the youngest generation of Americans.
The vaccine is also recommended for everyone at high risk, including health care workers, people who have had sex with multiple partners, and anyone who lives with, has sex with, or takes care of a person who has hepatitis B.
Once a person has been exposed to hepatitis B, speedy treatment with hepatitis B immune globulin (HBIG), coupled with vaccination, sometimes can prevent infection in adults. When mothers have hepatitis B, immediate treatment of their newborns can prevent the babies from developing chronic hepatitis.
For people who have not been vaccinated, hepatitis B can be prevented by not having unprotected sex, using condoms, and not using intravenous drugs.
* AIDS is short for acquired immunodeficiency (im-yoo-no-de-FISH-un-see) syndrome, the disease caused by the human immunodeficiency virus (HIV). In severe cases, it is characterized by the profound weakening of the body's immune system.
The U.S. and the World
In the United States, 4 million people (or 1.8 percent of the population) are estimated to have chronic hepatitis C, and 8,000 to 10,000 people a year die of it. An estimated 1 million to 1.5 million people have chronic hepatitis B, and 5,000 to 6,000 people a year die of it.
Worldwide, hepatitis B is more common, with 400 million people infected. In Southeast Asia and sub-Saharan Africa, where chronic hepatitis B is most common, 10 to 25 percent of all people may carry the virus. Hepatocellular carcinoma, the liver cancer linked to chronic hepatitis, is also most common in these areas. Worldwide, an estimated 170 million people have chronic hepatitis C.
In the United States, hepatitis B is most common in young adults (intravenous drug users, health care workers, prison inmates, and people, especially homosexual men, who have sex with many partners).
In developing countries, hepatitis B is most common in infants and young children, who get it from their mothers or within the family. When hepatitis B infects a child, it is much more likely to become chronic. That is why chronic B is more common in Asia and Africa than in the United States.
In addition, people should avoid contact with blood. They should not share razors, toothbrushes, or any items that have even the slightest amount of blood on them. Infected people should cover any wounds they may have and should dispose of or wash any tissues, clothes, or sanitary napkins that may contain their blood.
Hepatitis C: How Is It Prevented?
There is no vaccine for hepatitis C, and there is no reliable treatment after a person is exposed. Prevention consists of not sharing needles, avoiding contact with blood, limiting sexual contact, and using condoms, as with hepatitis B.
What Are the Symptoms of Hepatitis?
Acute hepatitis can cause loss of appetite, nausea, vomiting, fatigue, fever, jaundice, darkening of the urine, abdominal pain, arthritis (ar-THRY-tis; joint pain), and skin rash. Often symptoms are absent or so mild they go unnoticed.
The incubation * period is 15 to 45 days for hepatitis A, 15 to 150 days for hepatitis C, and 50 to 180 days for hepatitis B.
Chronic hepatitis can cause loss of appetite, tiredness, low-grade fever, and a general sense of "not feeling well" that doctors call malaise (ma-LAZE). Again, there are often no symptoms.
If the illness causes liver damage, additional symptoms can include weakness, weight loss, itching of the skin, enlargement of the spleen * , fluid in the abdomen, and a pattern of red blood vessels showing through the skin.
In severe cases, massive bleeding can occur in the stomach and the esophagus * , which requires emergency treatment. If the liver is no longer able to remove toxins from food, the brain can be affected, causing drowsiness, confusion, and even coma * .
How Is Hepatitis Diagnosed?
Viral hepatitis is diagnosed on the basis of symptoms and several kinds of blood tests. Liver enzyme tests indicate whether the liver is inflamed. If it is, other blood tests can look for specific evidence of hepatitis B or C and can help doctors distinguish between acute and chronic cases.
In chronic cases, doctors may look for liver damage by doing a biopsy (BY-op-see), in which a sample of the liver is removed by a needle through the skin and examined under a microscope.
In many cases, the first hint of hepatitis comes when a routine blood test done for a physical shows signs of abnormalities in the liver. In other cases, a person may try to donate blood and be rejected after his or her blood is tested.
How Is Hepatitis Treated?
For acute hepatitis, there is no specific treatment. In severe cases, people may be hospitalized to get proper fluids, fever control, and nursing care.
* incubation (in-ku-BAY-shun) means the period of time between infection and first symptoms.
* spleen is a large organ in the upper left part of the abdomen that stores and filters blood and also plays a role in making and breaking down blood cells.
* esophagus (e-SOF-a-gus) is the tube connecting the stomach and the throat.
* coma (KO-ma) is an unconscious state, like a very deep sleep. A person in a coma cannot be awakened and cannot move, see, speak, or hear.
For chronic viral hepatitis, the main treatment for years has been interferon alpha (in-ter-FEER-on AL-fa), a naturally occurring substance that interferes with the viruses' ability to reproduce themselves. Treatment requires injections three times a week for at least 6 months and often causes flulike symptoms or more serious side effects. People often relapse after treatment, which does not eliminate the virus completely.
In recent years, though, research has been yielding some promising new treatments. A drug called lamivudine, which was developed to treat HIV, also appears to be effective in treating chronic hepatitis B. For chronic hepatitis C, a combination of interferon alpha and a drug called ribavirin (ry-ba-VY-rin) seems to be more effective than interferon alone. Several other treatments are being studied.
People with chronic hepatitis need to be monitored closely by doctors, who may want to see them at least once or twice a year. Doctors will do liver enzyme tests to see how well the liver is functioning and may get blood tests, sonograms * , or even liver biopsies to check for cancer.
In cases of liver cancer or cirrhosis, sometimes the only treatment is a liver transplant, in which a person's damaged liver is replaced with a healthy organ taken from a deceased person. If the person can get a new liver in time, which is not always possible, such transplants usually are successful, although the virus eventually may damage the new liver as well.
Living with Chronic Hepatitis
Most people with chronic hepatitis do fine. They can go to school, play sports, work, have children, and live a life like anyone else's.
They need to make sure, however, that they do not put any extra stress on their liver. In the view of most experts, that means that they should never drink alcoholic beverages. They should not take any medicines, even common over-the-counter or herbal remedies, unless they specifically are approved by their doctor. They should not use illegal drugs. In most cases, they should be vaccinated against hepatitis A and against hepatitis B, unless they already have it.
As with other chronic illnesses, people with hepatitis often struggle with feelings of grief, worry, and isolation. Some feel a stigma because their illness often is associated with drug abuse, even though there are many other ways of getting it. Because most people know little about hepatitis, friends and even family may have unrealistic fears about catching it and may avoid the infected person. Counseling for the entire family sometimes can help.
Hepatitis A Vaccine
The vaccine for hepatitis A is thought to provide protection for at least 20 years, although the protection may last for life. The vaccine is administered in two or three doses during a 6-month interval.
The vaccine was tested in Thailand on children living in an area with a high rate of infection. More than 40,000 children aged I to 6 were given the vaccine in two or three doses. The children who received two doses achieved 94 percent protection, and those receiving three doses had almost 100 percent protection. In the cases that did occur, the symptoms were milder and lasted a shorter time.
People who are planning to travel to areas known to have hepatitis A should discuss vaccination with their doctors. Among those who may be candidates for the vaccine are:
Military personnel
Employees of day care centers
Institutional care workers
Laboratory workers who handle live hepatitis A virus
Handlers of primates that may harbor the hepatitis A virus
People living in, or relocating to, areas with a high rate of infection
Residents of communities experiencing a hepatitis A outbreak
People who engage in high-risk sexual activity
Users of injectable street drugs
* sonograms (SON-o-gramz) are images or records made on a computer using sound waves passing through the body,
* depression (de-PRESH-un) is a mental state characterized by feelings of sadness, despair, and discouragement.
The illness and sometimes the treatment can also cause fatigue and depression * . Infected people may need to get help from family and friends, seek treatment for depression, or modify their schedules to take it easier. Many groups now offer advice, support, and solidarity for people with chronic hepatitis.
Hepatitis without a Virus
Not all hepatitis is caused by a virus. It can also be caused by toxic chemicals such as carbon tetrachloride, a solvent used in some dry-cleaning fluids, or by some medications.
Many common medications, such as Dilantin (dy-LAN-tin) for epilepsy (EP-i-LEP-see) and isoniazid (i-so-NY-a-zid) for tuberculosis (too-ber-ku-LO-sis), cause hepatitis in a small fraction of the people who take them. But once the drug is stopped, the liver recovers. Life-threatening hepatitis can result, however, if a person accidentally or intentionally takes an overdose of many medicines, including the common over-the-counter pain reliever acetaminophen (a-set-a-MEE-no-fen).
Finally, some people experience a chronic condition called autoimmune hepatitis. In such people, it appears, the body's immune system attacks its own liver cells. Although treatment with corticosteroids * can improve the condition, it is often fatal unless a liver transplant is performed.
* corticosteroids (kor-ti-ko-STEER-oids) are medications that are prescribed to reduce inflammation and sometimes to suppress the body's immune response.
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