Hepatitis Flashcards
What are the different types of hepatitis?
Autoimmune A B C D E Alcoholic Ischaemic
What is autoimmune hepatitis?
Condition of unknown aetiology
Commonly seen in young women
3 types
Concurrent autoimmnue disease are often present
What are the 3 types of autoimmune hepatitis?
Type I: ANA and/or anti-SMA
Adults and children
Most common 80%
Type II: Anti-liver/kidney microsomal type 1 antibodies
Only children
Type III - Soluble liver kidney antigen
Middle aged adults
What are the presenting features of autoimmune hepatitis?
Acute - jaundice, fever Amenorrhoea Antibodies, raised IgG Liver biopsy showing inflammation Hepatomegaly and Splenomegaly Stigmata of chronic liver disease But patients can be asymptomatic
What is the management for autoimmune hepatitis?
steroids, other immunosuppressants e.g. azathioprine
liver transplantation
What is Hepatitis A?
Hepatitis A is typically a benign, self-limiting disease, with a serious outcome being very rare.
What causes Hepatitis A?
RNA picornavirus
transmission is by faecal-oral spread, often in institutions
2-4 week incubation
What are the presenting features of Hep A?
flu-like prodrome abdominal pain: typically right upper quadrant tender hepatomegaly jaundice cholestatic liver function tests
Who should have a Hep A vaccine?
people travelling to areas of high prevalence
people with chronic liver disease
patients with haemophilia
men who have sex with men
injecting drug users
individuals at occupational risk: laboratory worker; staff of large residential institutions; sewage workers; people who work with primates
What causes Hep B?
double-stranded DNA hepadnavirus
spread through exposure to infected blood or body fluids + vertical transmission from mother to child
6-20 week incubation
What are the presenting features of Hep B?
Fever
Jaundice
Elevated liver transaminases
What are some complications of hepatitis B?
chronic hepatitis (5-10%). ‘Ground-glass’ hepatocytes may be seen on light microscopy
hepatocellular carcinoma
Usually stays acute
Who is vaccinated against Hep B?
Children born in the UK at 2,3,4 months
Healthcare workers
IV drug users
Sex workers
What is the management for Hep B?
Acute - supportive
Chronic - pegylated interferon-alpha used to be the only treatment available
Reduces viral replication in up to 30% of chronic carriers
What causes Hep C?
hepatitis C is a RNA flavivirus
incubation period: 6-9 weeks
80% cases chronic
How is Hep C transmitted?
Risk from needlestick = 2%
Risk from vertical mother to child = 6% (higher in HIV mothers)
Risk from sexual intercourse = <5%
What features are present in 30% of those exposed to the Hep C virus?
a transient rise in serum aminotransferases / jaundice
fatigue
arthralgia
What is the investigation for Hep C?
HCV RNA
What is the outcome post Hep C infection?
around 15-45% of patients will clear the virus after an acute infection
the majority (55-85%) will develop chronic hepatitis C
What are some potential complications of Hep C infection?
Arthralgia, arthrtis
Eye problems (Sjorgen’s)
Cirrhosis
Hepatocellular cancer
What is the management for chronic hep C infection?
combination of protease inhibitors (e.g. sofosbuvir + simeprevir) with or without ribavirin are used
What is the aim of Hep C treatment and how is it measured?
Sustained virological response (SVR), defined as undetectable serum HCV RNA six months after the end of therapy
What are the side effects of Ribavirin?
Haemolytic anaemia
Cough
Teratogenic
What is Hep D?
single stranded RNA virus that is transmitted parenterally
Needs Hep B surface antigen to replicate
What is superinfection?
A hepatitis B surface antigen positive patient subsequently develops a hepatitis D infection
What is superinfection associated with?
high risk of fulminant hepatitis, chronic hepatitis status and cirrhosis
How is Hep D diagnosed?
via reverse polymerase chain reaction of hepatitis D RNA
Who is offered screening for Hep B?
All pregnant women
What are the main features of Hep E?
RNA hepevirus
spread by the faecal-oral route
incubation period: 3-8 weeks
common in Central and South-East Asia, North and West Africa, and in Mexico
What is ischaemic hepatitis?
Diffuse hepatic injury from acute hypoperfusion
Diagnosed with inciting event e.g. cardiac arrest
What is the route of transmission for viral hepatitis (A+E)?
Faecal-oral route
Hep A- Shellfish
How do Hepatitis viruses replicate?
RNA viruses bind to hepatocytes and kuffer cells
Enter cells via endocytosis
Release RNA into cell which binds to host ribosome
Translates polyprotein which is cut in to pieces before being released
What causes pruritrus in viral hepatitis?
Bile salts in the blood
What are the risks of Hep E?
Pregnancy -> Acute liver failure
Immunocompromised -> Chronic hepatitis
What would bloods/serology look like in current viral hepatitis (A+E)?
Raised AST/ALT
HepA
Anti-HAV IgM = indicated acute infection (no seroconversion)
Anti-HAV IgG = past infection, persists for life
Hep E
Anti-HEV IgM = current infection
Anti-HEV IgG = past infection, persists for years
Why does Hep A infection give life-long immunity?
Anti-HAV IgG antibodies persist for life
Is there a Hep E vaccine?
No
Why are Hep B and Hep D linked?
Need Hep B infection prev to get Hep D
Both DNA viruses
How does viral Hep B replicate?
Enters hepatocyte via fusing with membrane
Releases capsid into cell which enters nucleus
Uses host cell organelles to replicate
Is Hep B acute or chronic?
Chronic in 5-10% of cases
What is a serious complication of Hep B?
Hepatocellular carcinoma in chronic cases
Why do you get pale stool and dark urine in hepatitis?
Bilirubin released by hepatocytes are filtred by the kidneys and found in urine
No longer in stool
What is the management for Hep B?
Acute - resolves
Antivirals
Immune system modulators e.g. interferon alpha
How can Hep B be prevented?
Screening of donated blood
Avoid lifestyle risks
High risk pts vaccinated
If exposed pt can be give Hep B immune globulin
What are the symptoms of Hep C?
Majority asymptomatic
Extra-hepatic manifestations e.g. skin rash, renal dysfunction
How do you diagnose hepatitis C?
Raised AST/ALT
Anti-HCV antibodies
RT PCR if clinically suspected but viral serology -ve
Liver biopsy to assess degree of damage
What would serolgy show in active acute HBV infection?
HBsAg - postitive surface antigen in current infection
Anti-HBc IgM - acute disease
What would serolgy show in resolved acute HBV infection?
Anti-HBs seen in resolved infections
What would serolgy show in chronic HBV infection?
Anti-HBc IgG
HBsAg
No Anti-HBs (infection has not cleared)
What is ANA?
Anti-nuclear antibodies
What is ASMA?
Anti-smooth muscle antibodies
What are the investigative results in auto-immune hepatitis?
ALT>AST
Decreased serum albumin
Prolonged PT
Why are there differences in AST and ALT levels?
AST is found in other tissues than liver
What would Hep B serology show in someone who is vaccinated?
HBsAb
What would Hep B serology show in someone with a past infection?
No antigen
HBsAb present
IgG HBcAb
