Overview

What is hepatitis?

A healthy liver helps fight infections, stops bleeding, processes medications and removes toxins from the body. Hepatitis is a disease that affects your liver by causing it to swell and become inflamed. Common causes of hepatitis include some viruses that can damage liver cells, causing scar tissue to form and to prevent those cells from functioning. Depending on the type of hepatitis infection, the disease can be mild, chronic or deadly. Hepatitis affects millions of Americans.

Hepatitis A usually clears up on its own after a few months, and the liver returns to normal. It affects between 125,000 and 200,000 people in the United States each year. The condition rarely has complications and death is rare. When you have it, you can feel sick for at least a month. The virus is usually spread through the mouth from contaminated feces. That means you touched or ate something contaminated with feces containing the virus. It can also be contracted through sex, particularly oral-anal sex. Young children in diapers in day care settings are also more likely to spread or contract it. Children usually don't have symptoms. Hepatitis A is rarely spread through blood.

Hepatitis B can cause cirrhosis, liver cancer, liver failure and death. Hepatitis B is transmitted to someone who comes into contact with infected blood, semen, vaginal secretions and saliva. Using contaminated needles for illegal drugs can also spread the disease. Mothers can pass the disease during delivery to their child during delivery. It is not spread through urine, tears, feces or breast milk. Scarring of the liver is called cirrhosis, which keeps the liver cells from working as normal tissue is replaced by scar tissue. About 5,000 people die each year from liver cancer and cirrhosis caused by hepatitis B. When someone is first infected with the virus, they may not have symptoms, or they can get seriously ill. Most get better within a few months and never have another infection again. For others, the virus lingers for six months or longer, making this is a chronic infection. Most adults recover within a few months, developing antibodies that protect them from future hepatitis B infections. Infants and young children are much more likely to have the chronic form.

Hepatitis C is the most common blood-borne infection in the United States. About 10 percent of those infected are able to clear the infection from their bodies within six months. Most, however, develop chronic, or long-lasting, hepatitis C, which can lead to cirrhosis and liver cancer. Many people with hepatitis C develop some sort of liver damage. Liver problems from hepatitis C make this the leading cause of liver transplants. However, fewer than 3 percent ultimately die of chronic liver disease. The number of new infections each year has declined from an average of 240,000 in the 1980s to about 30,000 in 2003. Most infections are from illegal intravenous (through the vein) drug use. About 4 million Americans have been infected with hepatitis C. Of those, nearly 3 million are chronically infected.

Hepatitis D can only be acquired if the person has an active infection of hepatitis B. The virus cannot reproduce without the presence of the virus causing hepatitis B. If you have chronic hepatitis B and your symptoms suddenly worsen, your doctor should check for hepatitis D. The virus is spread through contact with infected blood and contaminated needles. You can also get the disease through sexual contact with someone who is infected.

Hepatitis E is rare in the U.S. and tends to go away on its own. The disease is contracted through feces similarly to the hepatitis A virus. Often outbreaks are associated with contaminated water supply in developing countries.

Toxic hepatitis

Chemicals, such as acetaminophen, that kill liver cells can cause toxic hepatitis. Taken in overdose, acetaminophen overwhelms the liver's normal processing of the medication, and the back-up system that the liver uses to get rid of the drug creates a dangerous substance. For an adult, a dose of 10 to 15 grams is all that is needed to damage the liver. Taking more than 25 grams can kill you. In children, the dosage that causes toxicity depends upon the size of the child, usually expressed in mg per kg. Generally, a child who gets more than 15 mg of acetaminophen per kg of their body weight (or 7 mg per pound) should be taken to an emergency room. Frequently, parents have a false sense of security about over-the-counter medications for children. When taken as directed, Tylenol® is a safe drug, but it comes in different strengths for adults, children and infants. Follow the dosage instructions. Infant Tylenol is a concentrated liquid that is three times as strong as Children's Tylenol. So giving the infant version to an older child and increasing the dosage could be dangerous.

Prognosis

The course of hepatitis can be difficult to predict. See a doctor if you think you have it. Treatment depends on the virus and the nature of your infection. Not everyone completely recovers from the disease and some go on to develop chronic hepatitis. But with proper medical care, you can be in control of your health, improving your chances to live a full, productive life.

More on Hepatitis

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This article was reviewed and updated June 2007.