Viral Hepatitis Flashcards by Taryn Miller

Acute hepatitis definition

Inflammation of the liver

Raised ALT/AST/jaundice/clotting derrnagments

How well did you know this?

Not at all

Perfectly

Chronic hepatitis definition

hepatitis virus present for more than 6 months

How well did you know this?

Not at all

Perfectly

Hepatitis A (HAV) type of organsims

picornavirus (ssRNA)

How well did you know this?

Not at all

Perfectly

Transmission of hepatitis A virus

Faeco-oral transmisson
Contaminated water and food with infected faeces or urine
Humans only reservoir

Virus can survive for months in contaiminated water
Virus shed via bilary tree into gut
no chronic carriage
good immunity after infection

How well did you know this?

Not at all

Perfectly

Hepatitis A- Clinical features

Incubation period 30 days

Many infections are asymptomatic.
Nausea, fever, malaise, and anorexia may last for 2-7 days before jaundice develops

usually self limiting illness

Mostly asymptomatic in children. Jaundice is more common in adults and is associated with dark urine, pale stools and tender hepatomegaly

How well did you know this?

Not at all

Perfectly

Treatment of hepatitis A

Symptomatic treatment-
maintain hydration, avoid alcohol
no role for vaccine or igG in the treatment.
Vaccine should be considered for close contacts

How well did you know this?

Not at all

Perfectly

Vaccine in hepatitis A

Inactivate virus
95% efficacy
Protection 4 weeks after 1st dose
2nd dose gives long term cover

Pre-exposure
-travelers/homosexual men/IVDU/Chronic liver lisease pts

Post-exposure

outbreak control
effective up to 7 days after exposure

How well did you know this?

Not at all

Perfectly

Alternative vaccine in hepatitis A

pooled immunoglobulin

Pre-exposure
-if vaccine allergic

How well did you know this?

Not at all

Perfectly

Hepatitis E type of virus

calcivirus (RNA)

How well did you know this?

Not at all

Perfectly

Transmission of hepatitis E

faeco-oral
faecal contamination of water supply
-minimal person-to-person transmission

How well did you know this?

Not at all

Perfectly

Incubation period for hepatitis E

40 days

How well did you know this?

Not at all

Perfectly

Clinical features of hep E

Anorexia, jaundice, nausea, joint pains, fever

In pregnant women (fetal and materanal mortality of 25%

Self-limiting illness

How well did you know this?

Not at all

Perfectly

Treatment of hep E

supportive

How well did you know this?

Not at all

Perfectly

Chronicity in hepatitis E

How well did you know this?

Not at all

Perfectly

Vaccine for hep E

How well did you know this?

Not at all

Perfectly

Hepatitis B type of virus

hepadnavirus (DNA)

How well did you know this?

Not at all

Perfectly

Transmission of hep B

Blood, sexual, Vertical (mother to baby)

Concentration of HBV in body fluids

High

blood
wound exudates

Moderate

semen
vaginal fluid
saliva

Low/not detectable

urine
faeces
sweat
tears
breast milk

Incubation period in hep B

2-6months

Clinical features of hep B

fever, fatigue, jaundice, myalgia, joint pains

Age at the time of illness determines:

severity of illness
risk of chronic HBV infection

Infection at birth/young child is asymptomatic but leads to chronic
infection an an adult is symptomatic but cleared

Complications of chronic HBV

chronic liver disease in 25%
cirrhosis
hepatocelular carcinoma
death

Hepatitis B serology

HBsAg (Hep B surface antigen)
HbsAB (hep B surface antibody)
cAb - core antibody
eAB- e anti-body

HBV DNA

HbsAG Hep B surface antigen

Carrier of infection

>6 months then chronic carrier

HbsAB (hep B surgace antibody)

Infection in the past and cleared through vaccination

cAB core antibody

previous infection through natural immunity

How to tell how infectious a patient is?

eAg - high infectivity | eAb - low infectivity

Chronic hepatitis markers | carrier >6 months

eAg +ve - high viral load - high risk of CLD and HCC - highly infectious eAg-ve - low viral load - lower risk of CLD and HCC - less infectious

Treatment for hepatitis B

Acute -no treatments Chronic - treat those with liver inflammation - small number, 5% will clear sAg spontaneously - aim of treatment is NOT to cure, but to suppress viral replication a/- to convert from eAg to eAb+

Two types of HepB therapy

Immunological - pergylated interforn alpha a. increases cellular immune responses b. lots of side-effects Antiviral drugs (nucleoside/tides) to suppress viral replication a. tenofovir b. entecavir

Prevention of HbV

Education (safe sex, injecting etc) screening (pregnancy etc) Protect blood supply & hospital supples Immunisation a. active (HBVsAG vaccine) (high risk grouups in UK and all in USA, most african/asian) b. passive (HBIG) -babies born to some HBV+ mothers, post exposure in non-immune

Pregnany - prevention of HBV transmission

Three interventions 1. HBC vaccination to all newborns 2. HBV immunoglobulins if eAG or high VL 3. tenofovir during the lst trimester if high VL

Hepatitis D type of virus

ssRNA

Transmission of hepatitis D

requires HBV to replicate Vertical tm rare acuired by: - co-infection with HBV - super-infection of chronic HBV carriers Increases risk of chronic liver disease

Hepatitis C type of virus

ssRNA flavivirus

Transmission of hepatitis C

injecting drugs transfusion + transplant -sexual/ verticlal rare

Prevention of hepatitis C

No vaccine, no post exposure prophylaxis No reliabble immunity after infection multiple genotypes of HCV

Incubation period of hepatitis C

6-7 weeks

Complications of hepatitis C

70% develop crhonic hepatitis 25% develop chronic liver disease (cirrhosis, liver transplantation, and hepatoceullar carcinoma multitude of extra-hepatic manifestations -cryglobuminaemia, vasculitis, glomerulopnephritis

HCV diagnosis

mostly asymptomatic Most diagnsed by screenign of high risk groups -drug users -immigrants to UK from high prevalance countries Anti-HCV IgG positive = chronic infection or cleared infection PCR positivity = current infection

Treatment

Aim - cure= PCR negative - Prevent and reverse fibrosis Who to treat - acute infections failing to clear virus by 3/12 -chronic infections (especially those with significant liver fibrosis and inflammation) -assess liver using LFT, liver biopsy and fibroscan Treatment - Pegalated interferon alpha - Ribavirin (anti-viral) - Protease inhibitor - Bocepravir and telapravir Sustained virological response = PCR -ve 6/12 after treatment