Wk 6: Hepatitis Flashcards
Viremia
Virus in the blood
What are some viruses which specifically infect the blood?
EBV, CMV, Hep C, HIV
How can you diagnose viremia?
Challenging when the length of the virus is short. Use host cell responses (IgG, IgM) with PCR (amount and virus in blood)
Hepatitis
General term referring to inflammation of the liver
Viral infections are always the cause of hepatitis? T/F
No. They are just 1. This could also be things like alcohol, drugs, autoimmune, metabolic diseaeses
List the 5 types of hepatitis
A, B, C, D, E
What are the differences between the types of hepatitis ?
How they enter the body. ABC are most common
Hepatitis A
Spread though poop, faecal-oral route of transmission. Usually Asymptomatic, stable the environment
What temperatures render Hep A inactive?
Freesing does nothing. But if you boil for more than 1 minute, it will become in active
What determines the severity of hepatitis A?
AGE
Adults are more commonly symptomatic with jaundice.
Most patients will recover :)
Hep A pathogenesis
Fever, malaise, appetite loss, nausea, abdominal pain, jaundice
What causes jaundice?
Bilirubin. A byproduct of old RBCs
How long does recovery normally take in HAV?
2 months and then you have lifelong immunity. Virus enters the blood stream from intestine or oropharynx
Which cells are targeted by the HAV?
Kupffer cells in the liver, then released in bile and stool
What is the most common way in which someone picks up HAV?
Contaminated water or food. Close personal contact or blood exposure-these are both more rare.
What is used to diagnose HAV?
detection of HAV-IgM in serum you can use this to determine past infection with EIA as well
Preventing HAV?
Vaccines. Seroconversion takes 4 weeks.
HCV transmission
Risk of infection from needlestick is 4-10%. Screening of blood products helps mitigate this. Sexual transmission. Hemodialysis.
Hepatitis C Virus (HCV)
Getting it younger is better than getting it older. Most patients are symptomatic. Progression to cirrhosis can occur and increase risk of liver cancer
How do you diagnose HCV in lab?
Anti-HCV serologic screening within 8 weeks of infection onset. Nucleic acid assay for HCV RNA for clinical management
is there a vaccine for hep C?
NO. Minimize risk of transmission with screening, high risk behaviour modification, blood and body fluid precautions
Antiviral treatment for HCV?
Newly developed antiviral treatments are 99% effective against HCV!
What leads to an increased prevalence in HBV?
Increased prevalence as people become sexually active…
HBV
Acute symptomatic or asymptomatic disease that will lead to immunity or may develop a chronic carrier state. can lead to end stage liver disease, cancer, cirrohisis…
The ______ the HBV is acquired, the _______ the risk of developing a chronic infection
Earlier in life, greater…
Infants have 90% chance, children 20-50, adults 5, olds 20-30…
Modes of transmission for HBV?
Sexual, parenteral, perinatal (screen if you’re pregnant)
Areas of high concentration for hep B
Blood, serum, wound exudates
MOderate concentration of HBV
Semen, vaginal fluid, salivare
Areas of low HBV
Urine, faeces, sweat, tears, breast milk
What is the rule of 3’s ?
From needlestick injuries, HBV 30% risk, HCV 3%, HIV 0.3% risk of developing!
Explain how we diagnose HBV?
Seology testing for HBV antigens and HBV antibodies/ testing uses antigens and antibody production. Focus on core protein, surface proteins, and e-antigen.
HBsAG
Surface antigen, infection
HBsAB
Antibody, recovery or immunity
HBcAB IgM
Antibody, acute infection
HBcAB IgG
Past core antibody, past or chronic infection
HBeAg
Envelope antigen, active replication stage
HBeAB
Virus no longer replicating, envelope antibody
What are the first 3 markers we will detect?
HBsAg and HBeAg and THEN HBcAb IgM
What tells us there is a chronic HBV infection ?
HBsAg, total IgG, anti-Hbe
What type of vaccine is used for HBV?
Recombinant with HBsAg. Can also use lamivudine which is an antiviral treatment. Liver transplant is only viable for final stages of disease
