HPB Medicine Flashcards
What is hepatitis?
Inflammatory disease of the liver, which can be acute or chronic
What are the acute causes of hepatitis?
Viral infections (hepatitis A-E / non A-E infections)
Autoimmunen
Drug reacitons
Alcohol
What are the chronic causes of hepatitis?
Hepatitis B +/- Hepatitis D Hepatitis C Autoimmune hepattis Alcohol Hyperlipidaemia (NAFLD) Drugs (methyldopa /nitrofurantoin)
Metabolic disorders (Wilson’s disease, alpha-1-antitrypsin deficiency, haemochromatosis)
What are the components of a liver screen?
Microbiology: Viral screen
Clinical chemistry: ferritin/transferrin, lipids, caeruloplasmin, AFP, alpha-1-antitrypsin
Immunology: autoantibodies
Abdominal USS
What type of virus is hepatitis A?
RNA picorna virus
How is hepatitis A transmitted?
What is the incubation period?
feco-orally
Incubation period is 2-6 weeks
What type of disease does Hepatitis A lead to?
80% = asymptomatic and naturally cleared
Does not lead to chronic liver disease and thus there are no carriers
Typically affects children / young adults
What is the treatment for hepatitis A?
No specific treatment, mortality 0.1%
What type of virus is hepatitis E?
RNA calcivirus
How is hepatitis E transmitted?
Feco-orally
What type of disease does hepatitis E lead to?
Similar to hepatitis A infection Epidemics of acute, self-limiting hepatitis with no progression to chronic disease
Common in indo-china, so consider if recent travel
Can cause severe disease in pregnant women
What kind of virus is hepatitis B?
Hepa-DNA virus, transmitted in the blood, semen and saliva via skin breaks or mucous membranes
Vertical transmission
What is the incubation period of hepatitis B?
1-6 months
Describe the structure of hepatitis B?
Inner core (HBcAg) surrounded by an outer envelope of surface protein (HBsAg)
Does Hepatitis B cause chronic disease?
Yes - around 10% of those infected will develop chronic disease and 1% will develop fulminant liver disease
What is the structure of hepatitis D?
Incomplete RNA virus, that can only cause infection in the presence of Hep B as it requires the Hep B virus for its own assembly
How is hepatitis D transmitted
Also transmitted by bodily fluids and can be both acute or chronic
Can be acquired simultaneously with Hep B or occur later
Patients with hepatitis D superadded to hepatitis B infection are more likely to develop fulminant liver disease
What is the structure of Hepatitis C?
RNA flavivirus, clinically similar to Hep B infection
How is hepatitis C transmitted?
Via bodily fluids - particularly common in IVDUs
Vertical transmission is rare and sexual transmission is uncommon
What are the long term effects of Hepatitis C?
85% become chronically infected
and 30% get cirrhosis in 20 years
For which hepatitis strains are there vaccines for?
Vaccines for A and B but not C
What are ‘non A-E infections’?
hepatotropic viral infections that cannot be typed
Describe the morphology of acute hepatitis?
Hepatocytes undergo degenerative changes (swelling and vacuolation) before necrosis and rapid removal
Necrosis is usually maximal in zone 3, as this is centrilobular and thus receives the least oxygenated blood
Extent can vary from scattered necrosis to multiracial necrosis leading to fulminant hepatic failure
What is chronic hepatitis?
Any hepatitis lasting more than 6 months
principal cause of chronic liver disease, cirrhosis and hepatocellular carcinoma
Describe the pathology of chronic hepatitis?
Chronic inflammatory cell infiltrates are present in the portal tracts
There may also be a loss of definition of the portal/periportal limiting plate, confluent necrosis and fibrosis
This eventually leads to cirrhosis
The overall severity is judged by the degree of inflammation and the extent of fibrosis / cirrhosis (staging), using various scoring systems such as the Child Pugh score
What is HbsAg?
Hepatitis B surface antigen
Marker of viral replication and thus ACTIVE infection
When does HbsAg appear and disappear?
Appears within 6 weeks of infection, disappears by 3 months after
What is HbsAb?
Anti-hepatitis B surface antibody
Marker of previously cleared infection / vaccination
What is HBeAg?
Hepatitis B E antigen
Marker of a high degree of viral replication (infectivity)
What is HBeAb
Hepatitis B e antibody
Marker of natural immunity to hepatitis B
What is HBcAb IgG?
Anti-hepatitis B core IgG antibody
Non-specific marker of current / previous infection (persists after 6 months)
What is HbcAb IgM?
Anti-hepatitis B core IgM antibody
Infection within the last 6 months (acute viral hepatitis)
What is HBV PCR?
The best marker of viraemia?
What markers indicate the immune tolerance phase?
HBsAg / HbeAg and PCR positive, transaminases negative
What markers indicate acute hepatitis?
All markers positive except HbsAb