Viral Hepatitis

Hepatitis A

Pathology:                         Single stranded RNA virus

Aetiology:                           Faeco-orally (contaminated food, water). Incubation time 2-6 weeks

Symptoms:                             Malaise, anorexia, nausea, vomiting, diarrhoea, headache, abdominal pain

Signs:                                    Jaundice, lymphadenopathy, hepatomegaly, splenomegaly

Investigations:                Bloods: LFTs show a raised AST, ALT and bilirubin

Serology: Hepatitis A IgM Positive

Imaging: Ultrasound Liver to exclude other causes of acute liver injury

Treatment:                        Conservative: Usually self-limiting

                                                       Vaccination: Immunisation for high risk patients leads to lifelong immunity

Complications:                Myocarditis, arthritis, vasculitis

Prognosis:                              Good prognosis with a 0.1% mortality.

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Hepatitis B

Pathology:               DNA virus, endemic in Asia, China and South America

Aetiology:                 Exchange of body fluids: sexual intercourse, vertical transmission from mother to baby, needle sharing, needle stick, blood transfusion. Incubation time 2-6 months

 Symptoms:             Asymptomatic, malaise, anorexia, abdominal pain, arthritis, rash

Signs:                          Jaundice

Investigations:      Bloods: LFTs show raised AST and ALT

Microbiology: Hepatitis B serology

Treatment:              Medical: Pegylated Interferon-alpha, Nucleotide Analogues such as Tenofovir to

     inhibit viral replication

Surgical: Liver transplantation and HBV immunoglobulin to prevent recurrence

Vaccination: Immunisation for high-risk patients

Complications:      Hepatocellular carcinoma, Cirrhosis. Co-infection with Hepatitis D has a faster

progression to complications.

Prognosis:               1% develop acute liver failure

90-95 % clear spontaneously

5-10 % become carriers

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Hepatitis C

Pathology:               RNA virus

Aetiology:                 Exchange of body fluids: sexual intercourse, vertical transmission from mother to baby, needle sharing, needle stick, blood transfusion. Incubation time 2-3 months

Symptoms:              Usually asymptomatic, lethargy, malaise and anorexia

Signs:                      Jaundice

Investigations:      Bloods: LFTs show raised AST and ALT

Microbiology: Hepatitis C PCR, viral load and genotyping

Treatment:              Medical: Pegylated Interferon-alpha, Ribavirin

                                        Surgical: Liver transplantation

Prognosis:                80% progress to chronic infection

Complications:      Risk of hepatocellular carcinoma and cirrhosis

Hepatitis E

Pathology:               RNA virus, endemic in Asia, Africa and Middle East

Aetiology:                 Faeco-orally. Incubation time 6 weeks

Symptoms:               Malaise, anorexia, nausea, vomiting, diarrhoea, headache, abdominal pain

Signs:                          Jaundice, lymphadenopathy, hepatomegaly, splenomegaly

Investigations:                    Bloods: LFTs show a raised AST, ALT and bilirubin

Serology: Hepatitis E IgM Positive

Imaging: Ultrasound Liver to exclude other causes of acute liver injury

Treatment               Conservative: Usually self-limiting

Complications:      Obstetric complications,

Prognosis: 20% mortality in pregnant women.