Beware as Fulminant liver failure is seen in 1 in 1000. The elderly and those with chronic liver disease are most vulnerable.
About
- Hepatitis A is an picornavirus
- Most commonly spread via faeco-oral contamination
- There is no chronic disease associated with hepatitis A
- Acute liver failure is seen in 1 in 1000
- Serious infection in those with Chronic HBV/HCV
Epidemiology
- Virus in faeces in sewage to seawater to undercooked shellfish to man
- The incubation period is usually 2-6 weeks but on average 30 days.
- Patients excrete virus before and after they are symptomatic
- A transient viraemia means it can be spread via blood
- It has been spread via sexual contact esp Homosexual men
Aetiology
- Virus replicates in hepatocytes and generate an immune response
- Infected cells targeted by CD8 T cells and NK cells
- Inflammation and zone 3 necrosis and bile duct proliferation
Clinical
- Nausea, sickness and general malaise for a number of weeks
- There is distaste for cigarettes
- Jaundice, Fever, Nausea, Abdominal pain
- Hepatomegaly which may be tender
- Splenomegaly in 20%
- Rare complications - optic neuritis, transverse myelitis, aplastic anaemia, thrombocytopenia, arthritis, vasculitis
- Admit if ill with dehydration, sickness, vomiting and malaise.
Investigations
- Serum IgM anti-HAV - Positive IgG anti-HAV suggests immunity
- ↑ ↑ AST and ALT (AST > 1000 ) and ↑ Bilirubin
Management
- Rest, take plenty of fluids and avoid alcohol and Paracetamol.
- Vaccinate those at risk and those with chronic liver disease in endemic areas
- Exposure to HAV picked up early can be treated with IM immune Globulin containing anti-HAV to prevent disease