Case 53: Hepatitis A

Question 1

what are some of the presenting symptoms of HepA?

Answer 1

1. fever
2. jaundice
3. dark yellow urine
4. pale colored stool
5. malaise
6. fatigue
7. abdominal pain
8. intermittent nausea
9. vomiting
10. loss of appetite

hepatomegaly but no splenomegaly

Question 2

what would the lab results of HepA show?

Answer 2

elevated ALT and AST (liver enzymes)

usually ALT > AST

Question 3

what are the characteristics of the HepA genome?

Answer 3

picornaviridae family = (+) naked ssRNA

only one serotype

Question 4

how is HepA transmitted?

Answer 4

fecal-oral route

in the United States, common-source outbreaks have been related to water and
food contaminated by infected food handlers

shellfish have been implicated in HAV
outbreaks in Atlantic and Gulf Coasts

Question 5

which populations are prone to HepA?

Answer 5

travelers to high or moderately
endemic countries, children in day care centers, and homosexual individuals are at
risk for development of infection

parenteral transmission (e.g., by way of injection
drug use) is rare, because the viremia is short

Question 6

what’s the incubation period of HepA?

Answer 6

average incubation period for hepatitis A is 30 days, with a range of 10 to 50 days

Question 7

where in the body does HepA replicate?

Answer 7

replicates in the liver, causing selective infection of hepatocytes, the parenchymal cells
of the liver

this leads to destruction of hepatocytes, a result of the host immunologic response to
the virus, as HAV-specific cytotoxic T cells destroy virus-infected hepatocytes

Question 8

which fluids can HepA be found in the body?

Answer 8

virus can be detected in bile, and it is shed in the stool

Question 9

which antiboies are present in the body against HAV?

Answer 9

IgM HAV Ab is generally present 5 to 10 days before the
onset of symptoms and is no longer detectable in the vast majority of patients 6
months later

following the immune response, the virus is rapidly cleared, and the
patient is no longer infectious. IgG HAV Ab, which also appears early in the course of
infection, remains detectable for the lifetime of the individual and confers lifelong
protection against reinfection

chronic infection does not occur following HAV
infection, and no chronic carrier state is recognized

Question 10

how do you treat HepA?

Answer 10

no specific treatment

supportive treatment only

Question 11

how do you prevent HepA?

Answer 11

transmission is fecal-oral so proper hygiene is important for prevention

also passive immunization with immunoglobulin given less than 2 weeks after exposure
can prevent 80% to 90% of cases

there’s also a killed vaccine available