Viral hepatitis Flashcards
(88 cards)
What is Hepatitis A?
Hepatitis A is typically a benign, self-limiting disease, with a serious outcome being very rare.
What is the incubation period for Hepatitis A?
The incubation period is 2-4 weeks.
What type of virus causes Hepatitis A?
Hepatitis A is caused by an RNA picornavirus.
How is Hepatitis A transmitted?
Transmission is by faecal-oral spread, often in institutions.
Does Hepatitis A cause chronic disease?
No, it doesn’t cause chronic disease.
What are the common features of Hepatitis A?
Common features include flu-like prodrome, abdominal pain (typically right upper quadrant), tender hepatomegaly, jaundice, and deranged liver function tests.
Are complications common in Hepatitis A?
Complications are rare and there is no increased risk of hepatocellular cancer.
Is there a vaccine for Hepatitis A?
Yes, an effective vaccine is available. After the initial dose, a booster dose should be given 6-12 months later.
Who should be vaccinated against Hepatitis A?
People travelling to or residing in areas of high or intermediate prevalence (aged > 1 year), people with chronic liver disease, patients with haemophilia, men who have sex with men, injecting drug users, and individuals at occupational risk (e.g., laboratory workers, staff of large residential institutions, sewage workers, people who work with primates).
What type of virus is Hepatitis B?
Hepatitis B is a double-stranded DNA hepadnavirus.
How is Hepatitis B spread?
It is spread through exposure to infected blood or body fluids, including vertical transmission from mother to child.
What is the incubation period for Hepatitis B?
The incubation period is 6-20 weeks.
What are the features of Hepatitis B?
Features include fever, jaundice, and elevated liver transaminases.
What are the complications of Hepatitis B infection?
Complications include chronic hepatitis (5-10%), fulminant liver failure (1%), hepatocellular carcinoma, glomerulonephritis, polyarteritis nodosa, and cryoglobulinaemia.
Who is vaccinated against Hepatitis B in the UK?
Children born in the UK are vaccinated as part of the routine immunisation schedule at 2, 3, and 4 months of age.
Who are considered at-risk groups for Hepatitis B vaccination?
At-risk groups include healthcare workers, intravenous drug users, sex workers, close family contacts of individuals with Hepatitis B, individuals receiving regular blood transfusions, chronic kidney disease patients, prisoners, and chronic liver disease patients.
What is the composition of the Hepatitis B vaccine?
The vaccine contains HBsAg adsorbed onto aluminium hydroxide adjuvant and is prepared from yeast cells using recombinant DNA technology.
What percentage of adults fail to respond to the Hepatitis B vaccine?
Around 10-15% of adults fail to respond or respond poorly to 3 doses of the vaccine.
What factors increase the risk of poor response to the Hepatitis B vaccine?
Risk factors include age over 40 years, obesity, smoking, alcohol excess, and immunosuppression.
Who should be tested for anti-HBs levels?
Testing for anti-HBs is recommended for those at risk of occupational exposure and patients with chronic kidney disease.
How should anti-HBs levels be interpreted?
Anti-HBs levels interpretation:
- > 100 mIU/ml: Adequate response, no further testing required, booster at 5 years.
- 10 - 100 mIU/ml: Suboptimal response, one additional vaccine dose should be given.
- < 10 mIU/ml: Non-responder, test for current or past infection, give further vaccine course.
What is the first-line treatment for Hepatitis B?
Pegylated interferon-alpha used to be the only treatment available, reducing viral replication in up to 30% of chronic carriers.
What factors predict a better response to pegylated interferon treatment?
Better response is predicted by being female, < 50 years old, low HBV DNA levels, non-Asian, HIV negative, and high degree of inflammation on liver biopsy.
What antiviral medications are used for Hepatitis B management?
Examples include tenofovir, entecavir, and telbivudine (a synthetic thymidine nucleoside analogue).