Acute Viral Hepatitis Flashcards
What is hepatitis?
Inflammation of the liver caused by viruses or non-infectious agents
What are the 5 viruses that can cause viral hepatitis?
Hepatitis A
Hepatitis B
Hepatitis C
Hepatitis D
Hepatitis E
How do we define an acute episode of hepatitis?
Systemic infection present for <6 months (often less than 6 weeks)
How do we define when a hepatitis infection has become chronic?
Presence of virus in blood for >6 months
What are the symptoms of chronic infections?
Typically asymptomatic (patient unaware) until development of late-stage disease complications
- Ascites
- Encephalopathy
How does hepatitis lead to ascites?
Damaged liver is unable to process blood properly. Increased pressure leads to portal hypertension.
Forces fluid to leak out into abdominal cavity.
How does hepatitis lead to encephalopathy?
Liver is damaged to the point it can no longer effectively filter toxins like ammonia from the blood.
Toxins accumulate and reach brain (neurological symptoms).
Can hepatitis B be cured?
No, hepatitis B cannot be cured.
If hepatitis B cannot be cured, how can we have acute infection?
Hepatitis B cannot be can’t be “cured” in the sense that the virus can be completely eradicated, but it can still present as an “acute” infection, meaning the illness has a sudden onset and typically resolves within a short period of time, allowing the body to fight off the virus without long-term damage
What is the preferred painkiller in hepatitis B patients?
Tylenol
Which two types of hepatitis virus can occur as a co-infection?
Why does this happen?
Hepatitis B and D
Hepatitis D (delta) is a defective virus that requires Hepatitis B to survive.
What is a HDV co-infection?
What is a HDV superinfection?
Co-infection: simultaneous infection of HBV and HDV
Super-infection: patient already has chronic HBV, but then HDV infection follows
- exacerbates liver disease, progresses to severe
Which virus types are the hepatic viruses?
HAV= RNA
HBV= DNA
HCV= RNA
HDV= RNA
HEV= RNA
How is HAV transmitted?
Fecal-oral
How is HBV transmitted?
Percutaneous
Sexual
Perinatal
How is HCV transmitted?
Percutaneous
Sexual
Perinatal (uncommon)
How is HDV transmitted?
Percutaneous
Sexual
Perinatal
How is HEV transmitted?
Fecal-oral
Zoonotic
Parenteral
Perinatal
Which of the hepatitis viruses can progress from acute to chronic disease?
HAV= No
HBV= Yes (most common in neonates)
HCV= Yes (common)
HDV= common in superinfection and rare in co-infection
HEV= No, unless patient is immunocompromised
Which of the hepatitis viruses most commonly progresses from acute to chronic infection?
Hepatitis B
Hepatitis C
Why is it the most common for hepatitis C to progress from acute to chronic?
Acute infection is rarely diagnosed and up to 80% become chronically infected
Which hepatitis virus has immunization for prevention?
HAV, HBV, HDV (from immunization of B)
Since HCV and HEV does not have immunization, what can we do for prevention?
HCV= blood donor screening, risk behaviour modification
HEV= ensure safe drinking water and adequately cooked pork products
Most acute infections of hepatitis are asymptomatic, but 25-30% will experience symptoms.
When there are symptoms, they appear to be similar in all types of viruses. What are they?
May include:
- Fever
- Myalgias
- Arthralgias
- Headache
- Constant Fatigue
- Right upper quadrant pain
- Jaundice
- Dark-urine
- Clay coloured stools
- Tender hepatomegaly
- Rise in aminotransferases (ALT>AST)
Can acute infection lead to acute liver failure?
Is it common?
Who is at increased risk?
Yes, but rare.
Pregnant patients are at particular risk
When should we put in an immediate referral for acute hepatitis?
- Prolonged INR
- Jaundice
- Encephalopathy
What are some drugs that can cause drug-induced hepatitis?
Acetaminophen
Herbal products:
- Buckthorn
- Chaparral
- Comfrey
- Germander
- Nutmeg
- Valerian
How do we identify what type of hepatitis virus is present?
Serologic markers (blood)
What do the following HAV markers indicate?
+ Total anti- HAV
+ Anti-HAV IgG
+ Anti-HAV IgM
+ Total anti- HAV
Total IgG and IgM
Acute, resolved infection or immunity
+ Anti-HAV IgM
Acute HAV infection
+ Anti-HAV IgG
Immunity from either vaccination or previous exposure (detectable for life and means lifelong protection)
What do the following HBV markers indicate?
+ HBsAG
+ Anti-HBs
+ HBsAg and Anti-HBs
+ Anti-HBc
- Anti-HBc
+ Anti-HBc IgM
+ HBeAg
+ Anti-HBe
+ HBV-DNA
+ HBsAG
Infection (either acute or chronic)
+ Anti-HBs
Immunity
+ HBsAg and Anti-HBs
Infection persists despite immunity (chronic infection)
+ Anti-HBc
Immunity developed from prior infection
- Anti-HBc
Immunity developed from vaccination
+ Anti-HBc IgM
Indicates acute infection or severe flare up of chronic infection
+ HBeAg
High degree of HBV infectivity and replication
+ Anti-HBe
Low degree of infectivity
+ HBV-DNA
Marker of viral replication/infectivity and used to monitor treatment
What do the following HCV markers indicate?
+ Anti-HCV
- Anti-HCV
+ HCVRNA
- HCVRNA
+ Anti-HCV
Indicates infection (acute or chronic)
Will remain positive for life despite clearance of infection
+ HCVRNA
Ongoing viremia
- HCVRNA
No active infection
When do we check HDV markers?
Only if HBsAg is positive
What do the following HCV markers indicate?
+ Anti-HEV
+ Anti-HEV IgM
+ Anti-HEV IgG
+ Anti-HEV
Antibodies for HEV
+ Anti-HEV IgM
Indicates acute infection
Can last up to 16 weeks
+ Anti-HEV IgG
Appears following infection and can last for years
What is the treatment of choice for acute viral hepatitis?
Often self-limiting, so antiviral therapy is mostly not indicated
Supportive therapy allows for majority of patients to recover completely
Exception: Hep C, treatment leads to favourable outcomes so should be considered on a case-to-case basis.
If we do decide to treat Hepatitis C infection, what drug do we use?
Direct-acting antiviral (DAA) agents
This is the same treatment for chronic hepatitis C
What are some non-pharms to recommend for hepatitis patients?
Avoid alcohol until full recovery
What vitamin supplementation is good for hepatitis?
No role for vitamin supplementation
What diet is good for hepatitis patients?
No dietary restrictions are needed
Does physical activity help with hepatitis patients?
No
Does hepatitis lead to increased or decreased INR?
Why?
Increased INR
Liver is in charge of producing majority of blood clotting factors.
Damage leads to less clotting (increased INR)
What do we do if patient has prolonged INR (>1.5) in acute hepatitis?
Vitamin K 10mg PO or IV
Can the Vitamin K be administered in different route?
IM and SC is available but increases risk of hematoma and bleeding
Do we need to treat acute symptomatic hepatitis B?
No. Immune competent adults are able to clear the infection.
Is there an exception to if we treat acute hepatitis B?
- Acute liver failure
- Severe course
(bilirubin >1.5mg/dL, INR>1.5) - Encephalopathy
- Ascites
In these exception cases of acute Hepatitis B, what do we use to treat patient?
Oral antivirals
- Tenofovir disoproxil
- Tenofovir Alafenamide
- Entecavir
What drug is contraindicated in acute hepatitis B?
Peginterferon-alpha therapy
If acute hepatitis B patient fails to clear infection after 6 months, how should they be managed?
Treat like chronic HBV
Is pre-or postexposure prophylaxis of HCV infection recommended?
No
Risk of transmitting through exposure is low and DAA can easily and effectively treat acute episodes. Therefore, don’t recommend prophylaxis
Regardless of cause, if patient has acute liver failure, what should we consider?
Liver transplantation
Most patient with hepatitis E will not require therapy. For those with more complicated symptoms (neurologic), what therapy should they consider?
Ribavirin
Is ribavirin safe in pregnancy and breastfeeding?
No, contraindicated
What is the best way to prevent viral hepatitis?
Vaccination
Hepatitis A vaccine is drug of choice for pre-exposure prophylaxis. How long of protection does it confer?
Up to 10 years
When are antibodies detectable following vaccine?
1 month in most patients
What is the dosing schedule for hepatitis A vaccine?
1st dose at 0 month
2nd dose 6-12 months later
What products do Hep A vaccines come in?
Single vaccine= Havrix
Combo vaccine with Hep B= Twinrix
Combo with typhoid= Vivaxim
Hepatitis B vaccine induces anti-HB production. Response generally decreases with age. how do we boost protection?
- Revaccinating with single booster (complete 3-dose series)
- Using higher concentration vaccines
How long does anti-Hbs levels last? Does protection diminish after those levels diminish?
10-15 years
Long-lasting protection remains due to immune memory
If patient is immunocompetent and vaccine was successful, is there a need for routine booster doses?
No
What is the dosing schedule for Engerix B (hep B vaccine)?
3 doses given at 0, 1, and 6 months
When is hepatitis B immune globulin preferred over the vaccine?
When someone has been exposed to Hep B but hasn’t been vaccinated (need immediate protection, as vaccine takes time)
No response to vaccine
What is the impact of hepatitis A in pregnancy?
No birth defects reported but may have increased risk of miscarriage or premature labour.
How do you manage hepatitis A infection during pregnancy?
No treatment. Mainly supportive.
How do you manage hepatitis A in breastfeeding?
Breastfeeding can be continued
What is the impact of hepatitis B on pregnancy?
No teratogenic effects, but there is an increased rate of miscarriage or premature labour.
Also risk of vertical transmission.
What increases the risk of vertical transmission. How do we manage this?
High viral load in mom
Antiviral therapy
If pregnant patient has high viral load, how do we manage this?
Treatment in third trimester if HBV DNA>200 000 units/mL
Tenofovir
Lamivudine
Telbivudine (rare in Canada)
Started at 28 weeks gestation and continued for 1 month postpartum
Of the antivirals, which is preferred?
Tenofovir
- better efficacy
- higher genetic barrier to viral resistance
Which antiviral is contraindicated in pregnancy?
Entecavir (teratogenicity)
Does mode of delivery affect likelihood of HBV transmission?
No
How do we further lower the risk of parent to child transmission on the newborn’s side?
Immunization at birth with hepatitis B immune globulin (HBIg) and hepatitis B vaccine
How do we manage hepatitis B in breastfeeding?
Safe to breastfeed if infant has received HBIg and HB vaccine within 12 hours of birth
When is breastfeeding contraindicated in hepatitis B patients?
If mother is experiencing cracking and bleeding of nipples.
Can restart if nipples heal.
If patient is on antiviral therapy, is breastfeeding ok?
Yes, breastfeeding is not contraindicated
How do we manage hepatitis C infection in pregnancy?
Mainly supportive
Treatment of patient is delayed until postpartum
No effective way to reduce vertical transmission. Mode of delivery does not modify risk
How do we manage hepatitis C in breastfeeding?
Safe to breastfeed as long as no cracks or bleeding
In summary, what are 4 initial biomarkers that should be tested with acute viral hepatitis?
ALT>AST
INR
Bilirubin
Albumin
