Hepatitis A

Hepatitis A is one of the most frequently reported diseases in the US.

Transmission usually precedes symptoms by 2 weeks when stool concentrations are highest. Patients are considered noninfectious 1 week after onset of jaundice.

Symptomatic patients may present with abrupt-onset fever, abdominal pain, malaise, and jaundice.

IgM anti-hepatitis A virus serology is the test of choice for diagnosis.

Common exam findings are hepatomegaly and clinical jaundice with marked elevation of serum aminotransferases (usually >1000 units/L).

No specific therapy is available and treatment is supportive.

Postexposure prophylaxis may be with active or passive immunization, depending on specific patient factors, and according to individual national guidelines.

Hepatitis A virus (HAV) is an RNA virus. It is not associated with chronic liver disease.[1]American Academy of Pediatrics. Hepatitis A. In: Red Book: 2003 report of the Committee on Infectious Diseases. 26th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2003:309-318.[2]Brundage SC, Fitzpatrick AN. Hepatitis A. Am Fam Physician. 2006 Jun 15;73(12):2162-8. http://www.aafp.org/afp/20060615/2162.html http://www.ncbi.nlm.nih.gov/pubmed/16848078?tool=bestpractice.com Mode of transmission is fecal-oral; therefore, it is more prevalent in environments with improper hygiene.[2]Brundage SC, Fitzpatrick AN. Hepatitis A. Am Fam Physician. 2006 Jun 15;73(12):2162-8. http://www.aafp.org/afp/20060615/2162.html http://www.ncbi.nlm.nih.gov/pubmed/16848078?tool=bestpractice.com Most infections in adults are symptomatic, whereas 70% of infections in children younger than 6 years, who are also the key reservoir for transmission, are asymptomatic.[3]Craig AS, Schaffner W. Prevention of hepatitis A with the hepatitis A vaccine. N Engl J Med. 2004 Jan 29;350(5):476-81. http://www.ncbi.nlm.nih.gov/pubmed/14749456?tool=bestpractice.com Average incubation period is 28 days.