HAV/HBV Flashcards
1
Q
Acute vs Chronic Hepatitis
A
- All viral hepatitis causes acute infections and some cause chronic (lasts >6 mo)
- Likelihood of developing chronic infection also depends on immune system, age, infectious agent, etc
2
Q
Hepatitis + Symptoms
A
- No differentiating symptoms between different viral hepatitis
- Symptoms: fever, fatigue, loss of appetite, N/V, pain, dark urine, joint pain, hepatosplenomegaly
3
Q
Hepatitis A
A
- Non-enveloped RNA virus known as a picornavirus
- Acute infection only
- Most recover and have lifelong immunity but it can cause fulminant hepatitis and death
- Most children <6 y.o. are asymptomatic
- > 6 y.o. is most likely to experience jaundice
- Incubation: ~28 days
- Can survive outside the body for months (extreme heat kills)
- Infectivity peaks 2 weeks before and 1 week after symptoms begin
4
Q
Hep A Transmission
A
- Poor sanitation, poor hygiene, contaminated food/water
- HAV shed in stool is primary spread via food/water contamination with infected fecal matter
- If good sanitation/safe water, seen more with injection drug use, male homosexual intercourse, travel to countries with high HAV rates
- Adequate chlorination of of water kill HAV in water
5
Q
Hep A Lab Diagnosis
A
- Elevated anti-HAV for identifying acute HAV (5-10 days post-exposure)
- Total anti-HAV includes IgM an IgG and doesn’t differentiate between acute and previous infection
- Elevated aminotransferase (ALT > AST), bilirubin (occurs second to ALT/AST), and alkaline phosphatase are also seen but connected to general hepatitis
6
Q
HAV Prevention
A
- Vaccination! - long term
- Monovalent vaccines inactivated, no preservative, given IM
- Seroconversion >=94% with first dose but booster recommended for maximal titers
- Don’t restart interrupted series
- Travelers should get first dose as soon as travel is considered
- Need at least 1 dose at least 1 mo before exposure to avoid pre/post prophylaxis
7
Q
HAV Vaccination Recommended Groups
A
- All children at least 1 y.o.
- Children 2-18 y.o. living in state/community where routine Hep A vaccination is implemented from high incidence
- Travel/work in countries with high/moderate endemicity
- MSM
- IDU
- Occcupational risk
- Clotting factor disorders patients
- Chronic liver disease patients
- International adoptions from at risk countries
8
Q
HAV + Immunoglobulin
A
- Used if vaccine can’t be used
- Provide passive transfer of antibody to body
- Most effective if given during incubation period
9
Q
Hep A Immunoglobulin Groups
A
- Children <12 mo
- Adults > 40 y.o.
- Immunocompromised
- Hemodialysis
- Chronic liver disease
- Allergy to vaccine/vaccine component
10
Q
Hepatitis B
A
- Transmitted via percutaneous or mucosal contact with infectious blood/fluids
- Survives outside body at least 7 days
- Incubation: ~90 days
- Often occurs < 40 y.o. and in absence of cirrhosis
11
Q
Hep B Presentation
A
- Signs/symptoms vary by age
- Most immunosuppressed adults and kids <5 y.o. are asymptomatic
- 30-50% of those >=5 y.o. have initial symptoms
12
Q
Hep B Risk Groups
A
- High prevalence HBsAg areas
- Infants born to infected mothers
- Contacts with chronic HBV infected persons
- IDU
- Sexually active non-monogomous long-term relationships
- MSM
- Health care/public safety wrokers
- Residents/staff at disabled persons facilities
- Chronic liver disease and hemodialysis patients
- Travel to risk areas
- Immunocompromised
13
Q
HBV Infection Course
A
- DNA virus that becomes part of host DNA
- Active or inactive phases
- Active infection requires treatment evaluation depending on ongoing liver injury
- Risk HBV disease progression is based on HBV serologies
- ~30% will develop cirrhosis
- Can develop liver cancer at ANY point in infectious process
14
Q
Common HBV Serology Tests
A
- HBsAg: protein found on surface of HBV and is detectable in acute or chronic infection
- anti-HBs: antibody produced after a successful vaccine series
- Total anti-HBc: indicates prior or ongoing infection, negative with lack of immunization, includes IgM and IgG
IgM = < 6mo (recent infection), IgG > 6 mo (prior infection)
15
Q
Other HBV Serology Tests
A
- HBeAg: present during active viral replication
- anti-HBe: formed in response to HBeAg and is present during antiviral therapy, predictor of long-term HBV clearance
16
Q
HBV Prevention
A
- Vaccination
- Single antigen and combination antigen options
- 3 series, no maximum time between doses
17
Q
HBV Vaccination Pearls
A
- 2nd and 3rd dose should be at least 8 weeks apart
- Not harmful to get extra doses
- Ok to give with other vaccines
- 2 dose series approved for 11-15 y.o.
- 30-50% protection with dose 1, 75% with dose 2, 96% with dose 3
- Lower protection seen in smokers, elderly, immunosuppressed, obese
18
Q
Heplisav-B
A
- New HBV vaccine
- Utilizes new adjuvant for more robust response
- Given as 2 doses, 1 mo apart for >=18 y.o.
- Higher seroprotection rates in various populations compared to traditional Engerix dosing
19
Q
HBV + Immunoglobulin
A
- Passive protection to prevent perinatal transmission
- Required to give to infants within 24 hours of birth to reduce transmission from HBV positive moms
- Not routinely used for adults
20
Q
HBV Vaccination Recommendations
A
- Pediatric patients at birth, <19 y.o.
- At risk for sexual exposure (MSM, non-monogamous)
- At risk for percutanous, mucosal, or blood exposure (jail, dialysis, health care, disabled, immunosuppressed)
- International travelers
- Chronic liver disease patients
- HIV positive
21
Q
When to Treat HBV
A
- HBV >= 2000 and ALT at UNL, recommend to treat
- Treat all cirrhotic patients
22
Q
HBV Goals of Therapy
A
- Long term suppression of HBV virus
- Induction of HBeAg loss (not actively replicating)
- Normalizing ALT levels (not being actively inflammed/changed)
23
Q
HBV Preferred Treatments
A
- Interferons
- Entecavir
- Tenofovir
24
Q
Interferons
A
- Immune modulating protein
- Causes lots of SE and risk of decompensation
- Rarely to never used
25
Q
Entecavir
A
- Nucleoside analogue inhibits HBV polymerase and activity against HIV
- 0.5 mg in treatment naive or non-lamivudine resistant infections
- 1mg in lamivudine refractory patients
- Safe in cirrhotic patients
26
Q
Tenofovir
A
- Nucleotide analog with activity against HBV and HIV
- TAF or TDF
- TDF 300 mg PO daily, renal adjustment
- TAF: 25 mg PO daily
- Safe in cirrhotic patients
27
Q
HBV Non-preferred Therapies
A
- All safe in cirrhosis, but limited use due to resistance concerns
- Adefovir: nucleoside analog to inhibit HBV, some HIV activity
- Lamivudine: nucleoside analog with HIV and HBV activity, good for immunosuppressed, resistance w/ >5 years of use
- Telbivudine: nucleoside analog for HBV specifically
28
Q
Immunosuppresed + HBV
A
- Start prophylaxis before immunosuppressive therapies
- Give vaccine if susceptible
- Can monitor instead of prophylaxis: check HBV DNA levels during and for 12 mo after cessation of therapy
- Test for serologic levels to see if at risk for reactivation
29
Q
HIV + HBV
A
- Test all for HIV before starting HBV treatment
- Can use antivirals that work for both
- If not needing HAART for HIV, use HBV specific meds to minimize resistance development to HIV medications
30
Q
Pregnancy + HBV
A
- High risk of transmission during delivery, especially with high viral loads
- Give mother lamivudine or tenofovir to decrease risk
- HBV vaccination and immunoglobulin for passive and active protection for newborn given at birth
