Viral Hepatitis B + D Flashcards
4 etiological facts about hepatitis B
Enveloped, partially ds-DNA virus
Acute or chronic course
Chronic = viraemia + hepatic inflammation for > 6 months
Transmission: SI, blood + vertical (mother to baby)
What antigens may be released by hepatitis B?
Core antigen (HBcAg) Surface antigen (HBsAg) e antigen (HBeAg): marker of high infectivity
Describe hepatitis D
Single-stranded RNA virus coated with HBsAg
What may histology show in hepatitis infection?
mild/ severe inflammation + changes
to cirrhosis
List 6 risk factors for hepatitis B
IVDU
Unscreened blood + blood products
Antenatal exposure (more likely to become chronic carriers)
SI with HBV carriers
From endemic area (Asia, Africa)
Genetic factors associated with varying rates of viral clearance
What is the incubation period of hepatitis B? Describe the course of infection
1-6 months (~3)
+/- Prodromal pre-icteric period 1-2 weeks post infection
Subclinical 70%
Symptomatic 30%
4 features of prodromal Sx of hepatitis B
Serum-sickness type illness Fever
Arthralgia
Urticaria/ maculopapular rash
What occurs after the prodromal symptoms of hepatitis B
Recovery: 4-8 weeks
1% develop fulminant liver failure
Chronic carriage may be diagnosed after routine LFT testing or if cirrhosis or decompensation develops
List 6 Sx of of symptomatic acute hepatitis B
Fever + arthralgia Nausea + anorexia Jaundice with dark urine + pale stools RUQ pain Hepatomegaly/ splenomegaly Occasionally: urticaria + maculopapular rash
Give 2 signs of chronic hepatitis B
May be no findings
May have signs of chronic liver disease or decompensation
List 3 investigations for hepatitis B
Viral serology
Bloods
Liver biopsy
What bloods are seen in hepatitis B?
High: AST, ALT, ALP, BR (ALT>AST)
Microcytic anaemia + Thrombocytopenia (indicative of portal HTN)
Clotting: High PT (in severe disease)
Describe the serology in acute hepatitis B
HBsAg +ve
HBeAG +ve
Anti-HBc IgM
Describe the serology in chronic hepatitis B
HBsAg +ve
HBeAg +ve or -ve (correlates with activity)
Anti-HBc IgG
Describe the serology in a patient with HBV cleared
Anti-HBs +ve
Anti-HBc IgG
How is hepatitis D detected?
IgM or IgG against HDV
PCR
Give 3 preventatory measures against hepatitis B
Blood screening
Safe sex
Instrument sterilisation
When is passive immunisation against hepatitis B utilised?
HBIG:
following acute exposure
to neonates born to HBeAg- +ve mothers (+ active immunisation)
What is the active immunisation against hepatitis B? Who is this for?
Recombinant HBsAg vaccine:
Individuals at risk
Neonates born to HB
Describe management of acute hepatitis B infection
Symptomatic tx (antipyretics, antiemetics + cholestyramine) + bed rest NOTIFIABLE disease
What drugs can be used in management of chronic hepatitis B infection?
Nucleoside/ nucleotide analogues (Tenofovir/ Entecavir)
List complications of viral hepatitis B
Cirrhosis Chronic HBV infection/ reactivation <1% get fulminant hepatic failure HCC Extrahepatic immune complex disorders (e.g. glomerulonephritis, polyarteritis nodosa)
What is the prognosis of patients with viral hepatitis B?
Infants: 90% become chronic
Adults: 10% become chronic
Of chronic infections, 20-30% develop cirrhosis
How does hepatitis B present?
Most children have asymptomatic acute infection
50% of adults have an asymptomatic acute infection (esp if HIV+)
