Acute & Chronic Hepatitis Flashcards
What is hepatitis?
Inflammatory disease of the liver
-can be acute or chronic
What are the acute causes of hepatitis?
Viral Infections (Hep A-E/Non A-E infections)
Autoimmune
Drug reactions
Alcohol
What are the chronic causes of hepatitis?
Hep B +/- Hep D Hep C AI hepatitis Alcohol NAFLD Drugs (methyldopa/nitrofurantoin) Metabolic disorders
What are the metabolic disorders that cause chronic hepatitis?
Wilson’s disease
a-1-antitrypsin deficiency
Haemachromatosis
What investigations make up a liver screen?
Microbiology - viral screen
Clinical chemistry - ferritin/transferrin, lipids, caeruloplasmin, AFP, a-1-antitrypsin
Immunology - autoantibodies
Abdominal USS
What are they key features of Hepatitis A?
RNA virus Faeco-oral transmission Incubation period 2-6wks 80% asymptomatic Acute liver disease only Affects children/young adults
What are the key features of Hepatitis E?
RNA virus
Faeco-oral transmission
Acute, self-limiting hepatitis
Can cause severe disease in pregnant women
What are the key features of Hepatitis B?
DNA virus Transmitted via blood/semen/saliva Vertical transmission most common Incubation period 1-6mo Virus has inner HBcAg core surrounded by HBsAg 10% chronic 1% fulminant
What are the key features of Hepatitis D?
Incomplete RNA virus
-can only cause infection in presence of Hep B
Transmitted by bodily fluids
Acute OR chronic
Likely to develop fulminant liver disease
What are the key features of Hepatitis C?
RNA virus Transmitted via bodily fluids Common in IVDUs Vertical/sexual transmission rare 85% chronic 30% cirrhosed
For which hepatitis viruses are there vaccines?
Hep A
Hep B
What are the non A-E infections?
10-15% hepatotrophic viral infections cannot be typed
What other viruses can cause acute hepatitis?
CMV
Yellow fever
HSV (immunocompromised pts)
What is the underlying pathophysiology of acute hepatitis?
Hepatocytes undergo degenerative changes
- swelling & vacuolation THEN
- necrosis & rapid removal
What is the pattern of necrosis in acute hepatitis?
Maximal in zone 3 (centrilobular)
Varying extent (scattered to multiacinal necrosis)
Leads to fulminant hepatic failur
What is the underlying pathophysiology of chronic hepatitis?
Any hepatitis lasting >6mo
Main cause of chronic liver disease/cirrhosis/hepatocellular carcinoma
Chronic inflammatory cells present in portal tracts
-loss of definition of portal/periportal limiting plate
-confluent necrosis
-fibrosis
Leads to cirrhosis
What features are used to judge the severity of chronic hepatitis?
Child-Pugh Score
- degree of inflammation (grading)
- extent of fibrosis/cirrhosis (staging)
What are the serological markers of Hep B infection?
HBsAG - marker of viral rep, active infec (6w-3mo)
HBsAb - marker of prev infec
HBeAg - marker of infectivity
HBcAb IgG - non-specific marker of current/prev infec
HBcAb IgM - infec w/i 6mo
HBV PCR - viraemia
What serological markers of Hep B infection suggest immune tolerance?
HBsAg (+ve)
HBeAg (+ve)
PCR (+ve)
Transaminases (-ve)
What serological markers of Hep B infection suggest acute hepatitis?
HBsAb (-ve)
All other markers (+ve)
What serological markers of Hep B infection suggest chronic hepatitis?
HBsAb (-ve)
all other makers (+ve)
HBeAg (+ve)
HBeAb (-ve)
What serological markers of Hep B infection suggest natural immunity?
HBsAg (-ve) HBsAb (+ve) HBcAb IgG (+ve) HBcAb IgM (-ve) HBeAg (-ve) HBeAb (+ve)
What serological markers of Hep B infection suggest vaccination?
HBsAg (-ve) HBsAb (+ve) HBcAb IgG (-ve) HBcAb IgM (-ve) HBeAg (-ve) HBeAb (-ve)
What are the two stages of acute hepatitis?
Pre-ictal
Ictal