Hepatitis B

Question 0

Why is HBcAg not routinely detected?

Answer 0

Because HBcAg is sequestered within an HBsAg coat.

Question 1

Currently available lab test for Hep B?

Answer 1

HBsAg
Anti-HBs
IgM anti-HBc
IgG anti-HBc
HBeAg
Anti-HBe

Question 2

Which Hep B lab test is most helpful in determining whether the pt is in the acute phase of viral hepatitis?

Answer 2

IgM anti-HBc is a marker for acute (less than 6 months ) hepatitis

1. It appears soon after the onset of infection and the detection of HBsAg.
2. It precedes by many weeks detectable levels of anti-HBsAg.
3. It generally disappears after 6-8 months.

Question 3

Which lab market indicate infectivity for Hep B?

Answer 3

HBeAg

It may persist for years in pt with chronic disease and is associated with high infectivity.

Question 4

Which marker indicates chronicity of Hep B?

Answer 4

1. HBsAg remains detectable beyond 6 months in chronic hepatitis.
2. HBeAg may persist for years in pt with chronic disease.
3. Persistent elevated ALT.

Question 5

The relationship of Age of infection of Hep B and the risk of become chronically infected?

Answer 5

The likelihood of becoming chronically infected with hepatitis B is inversely related to the age at which the infection occurs.

Question 6

What percent of Infants born to HBsAg-positive mothers will become Hep B carrier?

Answer 6

Up to 90%

Question 7

What percent of children infected Hep B before the age of 5 will become Hep B carrier?

Answer 7

Between 25-50%

Question 8

What percent of acutely Hep B Infected adults will become chronically infected?

Answer 8

6-10%

Question 9

Transmission of HBV in the US?

Answer 9

• most HBV in fiction in the US with known routes of transmission result from sexual contact.

Question 10

Hepatitis D virus

Answer 10

1. A defective virus
2. Co-infection with HBV is necessary for the replication and clinical expression of HDV
3. Preventing hepatitis B through vaccination with HBV vaccine will protect against hepatitis D

Question 11

Risk of seroconversion due to sharps injury from a known positive source?

Answer 11

HBV—-6-30% if not vaccinated
HCV—-~2%
HIV—-0.3%