Hepatitis A is transmitted by an enteric RNA virus that causes typical symptoms of viral hepatitis in older children and adults, including anorexia, nausea and jaundice. Young children may be asymptomatic. Fulminant hepatitis and death are rare. Chronic hepatitis does not occur. The diagnosis is made by an antibody test. The treatment is symptomatic. Vaccination and previous infection provide protection.
See also causes of hepatitis and overview of the acute viral hepatitis.)
Hepatitis A is transmitted by an enteric RNA virus that causes typical symptoms of viral hepatitis in older children and adults, including anorexia, nausea and jaundice. Young children may be asymptomatic. Fulminant hepatitis and death are rare. Chronic hepatitis does not occur. The diagnosis is made by an antibody test. The treatment is symptomatic. Vaccination and previous infection provide protection. See also causes of hepatitis and overview of the acute viral hepatitis.) The hepatitis A virus is a single-stranded RNA picornavirus. It is the most common cause of acute viral hepatitis and most often occurs in children and young adults. In some countries,> 75% of adults have been exposed to HAV. In the US, an estimated 3,000 cases occur annually-a decline from 25,000 to 35,000 cases annually before the hepatitis A vaccine in 1995 was available (see CDC Hepatitis A FAQs). The propagation of HAV occurs mainly fecal-oral route, so very often in areas with poor hygiene. By Kontaminerung of drinking water and food-related epidemics occur mainly in developing countries; the consumption of contaminated raw shellfish can sometimes be the cause. Sporadic cases are also common, usually due to a transmission from human to human. The virus appears in the stool before symptoms occur and usually disappears a few days after the onset of symptoms. Therefore, there is usually no infectivity if the hepatitis becomes clinically evident. When hepatitis A virus no chronic carrier state is known. Acute hepatitis does not cause chronic hepatitis or cirrhosis. Symptoms and ailments in children <6 years, 70% of hepatitis A infections are asymptomatic, and in children with symptoms jaundice is rare. In contrast, most older children and adults have typical manifestations of viral hepatitis, including anorexia, malaise, fever, nausea and vomiting; Jaundice occurs in about 70%. Manifestations typically disappear after about two months, but in some patients the symptoms persist or recur up to 6 months. The recovery from acute hepatitis A is usually concluded. Rarely occurs fulminant hepatitis. Diagnosis Serological tests should therefore viral hepatitis are the differential diagnosis, distinguished from other diseases that cause jaundice in the early diagnosis of acute hepatitis (Simplified diagnostic approach to potential acute viral hepatitis.. If an acute viral hepatitis is suspected, the following tests for screening are conducted on hepatitis viruses A, B and C: IgM antibody to HAV (IgM anti-HAV) hepatitis B surface antigen (HBsAg) IgM antibody to hepatitis B core (anti-HBc IgM) antibody to hepatitis C virus . (anti-HCV) If the IgM anti-HAV test is positive, acute hepatitis a is diagnosed, the IgG antibody to HAV (IgG anti-HAV test) done (see table: hepatitis a serology) to to distinguish acute from previous infection. A positi ver IgG anti-HAV test points to HAV infection or acquired immunodeficiency. There is no further investigation for hepatitis A. HAV is only during the acute infection in serum and can not be detected with currently available at the clinic tests. The IgM antibody typically develops during the early phase of infection, it reaches its highest titers approximately 1-2 weeks after the jaundice. He takes within a few weeks off again, followed by the development of protective IgG antibody (IgG anti-HAV), which persist throughout life. Therefore, the IgM antibody is a marker for acute infection, whereas IgG anti-HAV displays only a previous HAV infection and immunity to HAV. Hepatitis A serology markers Acute HAV infection before HAV infection * IgM anti-HAV + - IgG anti-HAV - + * HAV does not cause chronic hepatitis. HAV = Hepatitis A virus, anti-HAV IgM = IgM antibodies to HAV. Therapy Supportive treatment No specific treatment softens the course of acute hepatitis, including hepatitis A. Alcohol should be avoided because it increases the liver damage. Restrictions in diet or physical activity incl. The often prescribed bed rest have no scientific basis. Most patients can resume safe to work after the jaundice has subsided, even if the transaminases are still increased. In the cholestatic hepatitis, the administration of cholestyramine can be 8 g p.o. 1 to 2 times reduce the itching daily. The presence of a viral hepatitis is reportable. Prevention Good personal hygiene helps prevent the fecal-oral transmission of Hepatitis A. Protective measures are recommended, but isolation of patients is of little help to prevent HAV dissemination. Leaks and contaminated surfaces in the home of the patient can be cleaned with diluted bleach. Vaccinations The hepatitis A vaccine is recommended for all children starting from the first year of life, with a second dose 6 to 18 months after the first (see Table: Recommended vaccination schedule for the age of 0-6 years). should be a Präexpositions-HAV vaccination (see Adult Immunization Schedule) are provided for travelers at high or medium HAV endemicity Diagnostic laboratory workers Men who have sex with men, people who illegal drugs with or without injection use people with chronic liver disease (including chronic hepatitis because they have C) have an increased risk for the development of fulminant hepatitis due to HAV. Persons who receive clotting factor concentrates people in close contact with an adopted child of other nationalities during the first 60 days after arrival from a country with high or intermediate endemicity HAV will have. A Preexpositions-HAV Prphylaxe (HAV preexposure prophylaxis) can be considered for kindergarten employees and military personnel into consideration. A number of HAV vaccines are commercially available, each with different doses and dosing schedules. They are safe and provide a protective effect in about 4 weeks and also have a long-term protective effect (probably> 20 years). Previously, travelers were advised to get the vaccine to the hepatitis A vaccine ? 2 weeks prior to the trip; those who leave for <2 weeks, include Standard immunoglobulins should be given. Current evidence suggests that immunoglobulins sind.Postexpositionsprophylaxe only necessary for older travelers and travelers with chronic liver disease or other chronic disease A post-exposure prophylaxis should be carried out at family members and close contacts of patients with hepatitis A. In healthy, unvaccinated patients aged 1 to 40 years, a single dose of the hepatitis a vaccine is being administered. In other patients, especially in those> 75 years prevented with chronic liver disease and patients with weakened immune systems standard immunoglobulin (formerly Immunserum- globulin) hepatitis A or reduces the severity. A dose of 0.02 ml / kg i.m. is usually recommended, but some experts advise to 0.06 ml / kg (3 to 5 ml for adults). There can be up to 2 weeks after exposure, but the sooner, the better. Key points The hepatitis A virus is the most common cause of acute viral hepatitis; It is spread by the fecal-oral route. Children <6 years of age can be asymptomatic; older children and adults have loss of appetite, nausea and jaundice. Fulminant hepatitis is rare and chronic hepatitis, cirrhosis and cancer do not occur. Treatment is supportive. Routine vaccination is starting at age 1 recommended for all. Vaccinate people with risk (for example, travelers to endemic areas, laboratory technicians.) And provide them for post-exposure prophylaxis with standard immunoglobulin or - for some - with vaccination. For more information CDC Hepatitis A FAQs