Hepatitis A is an infection and inflammation of the liver caused by the hepatitis A virus. It is one of several types of hepatitis.
The liver is an important organ located in the upper right quadrant of the abdomen. It is responsible for: filtering the blood and removing and metabolizing many drugs and toxins. making bile, a substance that aids in the digestion of fats, the excretion of fatty and other potentially harmful substancesprocessing fats on carriers (including cholesterol) and storing sugars (glycogen), helping the body transfer and store energy.making important proteins, such as those involved in blood clottingmetabolizing medications, such as barbiturates, sedatives, and amphetaminesstoring vitamins A, B12, D, and several of the B-complex vitamins. The liver also stores iron and copper.making albumin a protein that helps maintain fluid volume in the blood stream.helping breakdown and recycle red blood cells.
The liver is susceptible to multiple hepatitis viruses. These viruses can cause sudden, and/or chronic severe inflammation of the liver cells. Infection can occur at any age.
Yellowing of the eyes and skin, called jaundice, is often the first sign of a problem, but less often so in children. Unlike other hepatitis viruses, hepatitis A does not generally cause symptoms or disease in other parts of the body.
After exposure to the virus, the hepatitis usually occurs within 2 to 4 weeks. In industrialized countries, hepatitis A usually occurs in an epidemic setting, that is, a cluster of cases in a population that has previously been unexposed and spreads the infection one to another. These cases in an epidemic may also have a common source of exposure.
Some parts of the world have persistent, ongoing hepatitis A in a large part of the population. Vaccination in these areas has been successful in markedly decreasing the disease burden of hepatitis A
Symptoms can range from nothing through mild, moderate to severe and may include: nausea jaundice. This skin yellowing usually lasts a week or two. malaise, or a vague feeling of illnessfatiguedark urinediarrheafevera somewhat enlarged and tender liver or abdomenweight loss as a result of loss of appetitemyalgias (muscle pains)
The symptoms gradually improve. Children with hepatitis A often do not have symptoms. In general, the older a person is at the time of acute hepatitis A infection, the worse the illness will be. Rarely, acute fulminant hepatitis, which involves severe liver cell destruction and loss of liver function may occur. It can be fatal. Symptoms include: an enlarged, painful liverenlarged spleensevere jaundicesusceptibility to bleedingencephalopathy, a disorder in the functioning of the brain due to a build up of toxins.aplastic anemia in rare cases. Aplastic anemia is a condition in which the bone marrow cannot make enough red and white blood cells, and platelets.
Hepatitis A is generally spread by food and water that is contaminated with the virus from an infected person. This is called "fecal-oral" spread because the virus is excreted in the urine and stool. So in certain areas, sewage transmits the virus when it contaminates food or water. Rarely, it is spread when a person is exposed to the blood of another person with acute hepatitis.
The following groups have a higher risk for this disease: military personnel (due to close contact)homosexual malestravelers to countries with high rates of hepatitis A infections. healthcare workers. injection drug users.persons with other liver diseases.patients with clotting factor disorders who receive factor replacement preparations (less common).
Outbreaks of hepatitis A can occur and spread in child care centers when children have asymptomatic infections.
To prevent the infection, a person should: eat only properly prepared food and drink clean waterwash hands well after using the toilet or diapering a childhave an injection of serum immunoglobulin if exposed to the virus and is not allergic.have the hepatitis A vaccine. The vaccine is usually given in 2 injections that are 6 to 12 months apart. Both immunoglobulin and hepatitis A vaccine can safely be given together.
Anyone who has had hepatitis A is immune for life.
The healthcare provider may suspect hepatitis A after doing a physical examination if a patient has appropriate symptoms and signs. Diagnosis may also be suspected if liver function tests are drawn.. Another specific blood test for antibodies against hepatitis A, drawn at the same time as the liver function tests can confirm that hepatitis A is the cause of the symptoms.
For most people, hepatitis A disappears completely after the acute infection and there are no long-term problems. If hepatitis A infection occurs in someone who is debilitated by another disease, especially liver disease, it can be fatal.
Occasionally with acute infection other problems can occur: acute fulminant liver failure, a serious complication that can be lethal or can require a liver transplantaplastic anemia, which is a bone marrow failure problem. It results in low blood cells including red cells, platelets, and white blood cells.
Anyone who comes into contact with a person with hepatitis A is at risk for the disease. It is most important that no one is exposed to the stool or urine of an infected person. Other bodily secretions are not likely to cause an infection.
Finding the source and preventing additional exposure to that source also is very important. People with active hepatitis A and all those in contact with them need to wash their hands after using the toilet. Infected people may need to take 1 to 4 weeks of time off from work to not expose healthy people.
Treatment of hepatitis A is supportive and includes: bed restdrinking extra fluids to prevent dehydrationavoiding unnecessary medications, especially those that may hurt the liver (like acetaminophen
Antiviral and anti-inflammatory medications are not helpful for the treatment of hepatitis A. Acute fulminant hepatitis can cause life-threatening liver failure. This requires hospitalization and potential treatment for bleeding, as well as for any neurological and nutritional problems from liver failure. Sometimes, the only effective treatment is a liver transplant.
The side effects of treatment for routine hepatitis A are minimal. There are few problems with the vaccine. . A person who has been exposed to the virus and is injected with serum immunoglobulin as a precaution may feel some pain at the injection site or have a mild, brief flu-like illness. Some people (those with immunoglobulin A deficiency) may have a bad reaction to the immune globulin.
A liver transplant for acute fulminant hepatitis can have many complications, including failure or rejection of the new liver. After a liver transplant, a person will need to take powerful anti-rejection medications for the rest of his or her life. Side effects of these medications increase the risk for infections, certain cancers, and other problems.
After the hepatitis A is resolved, the person will no longer need medications. He or she can return to normal activities, even if some jaundice remains.
The healthcare provider will often repeat the liver function tests to assure that they are normal. Other tests, like liver ultrasound or CAT scans, are usually not required.