Hepatitis B

Hep B | HBV |

Overview

  • There is no such thing as a ‘healthy carrier’.
  • Infection causes acute, which may progress to chronic, hepatitis.
  • Transmission occurs from mother to child (vertical) via parenteral exposure (shared injection equipment) or through sexual or household contact (horizontal).
  • The risk of developing chronic hepatitis B is highest if infected at birth or <5 years (>90%). Infection as an adult has a <5% risk of progression to chronic hepatitis B.
  • Prevalent among Aboriginal and Torres Strait Islander people living in remote areas and among culturally and linguistically diverse populations.

Cause

Hepatitis B virus (HBV), a double-stranded DNA virus.

Clinical presentation

Symptoms
Asymptomatic infection: common
Acute hepatitis: lethargy, nausea, fever, anorexia for a few days then jaundice, pale stools and dark urine, incubation 45-180 days (mean: 60 days)
Chronic hepatitis: infection lasting over 6 months, can be life-long
Complications
Cirrhosis: ankle swelling, ascites, GI bleeding, encephalopathy, jaundice
Hepatocellular carcinoma: abdominal mass

Diagnosis

Decision making tool for hepatitis B

TestSite/SpecimenConsideration
AST, ALT Blood Raised in acute and chronic infection
HBsAg Blood Current hepatitis B infection
Anti-HBs Blood Immunity to hepatitis B infection
Anti-HBc Blood Previous exposure
HBeAg Blood Associated with higher infectivity
Anti-HBe Blood Associated with lower infectivity
HBV DNA Blood Viral replication
AST – Aspartate aminotransferase 
ALT – Alanine aminotransferase 
HBsAg – Hepatitis B surface antigen 
Anti-HBs – Hepatitis B surface antibody 
Anti-HBc – Hepatitis B core antibody 
HBeAg – Hepatitis B envelope antigen 
Anti-HBe – Hepatitis B envelope antibody 
HBV DNA – Hepatitis B DNA (i.e. viral load)

Investigations

Patients of unknown status should always have 3 initial tests performed (HBsAg, Anti-HBs and Anti-HBc) to determine infection status and the need for vaccination. All 3 tests are Medicare rebateable simultaneously. Specify the above tests on the request form rather than ‘hepatitis B serology’ and/or include “? Chronic hepatitis B” in the clinical notes section.

The National Hepatitis B Testing Policy provides more detail.

 

Management

Management
SituationRecommended
Acute hepatitis: HBsAg positive, unwell, raised LFTs Possible acute hepatitis B, needs supportive care, hospital admission if unwell or deteriorates
Chronic hepatitis: HBsAg positive for >6 months Needs further investigation and possible treatment with antiviral agents and specialist review/management
Cirrhosis: ankle swelling, ascites, gastrointestingal bleeding, encephalopathy, jaundice

Specialist review if suspected. All patients with cirrhosis require treatment with antiviral therapy.

Treatment advice

Treatment is available from specialist services and suitably trained GPs. It will generally consist of oral antiviral therapy which is taken on a long-term basis. Less commonly, pegylated interferon is used.

Other immediate management

Special treatment situations

Special considerations

Consider seeking specialist advice before treating any complicated presentation.

SituationRecommended
Pregnant women 
pregnancy
Needs specialist review. Infant needs hepatitis B vaccination and immunoglobulin (HBIG) at birth, mother may need antiviral therapy to reduce transmission at birth.

Treatment advice

Treatment is available from specialist services and suitably trained GPs.

Contact tracing

See Australasian Contract Tracing Manual - Hepatitis B for more information.

Follow up

Retesting

Prior infection and clearance provides lifelong immunity to re-infection. Patients with resolved infection may experience a hepatitis B flare if immunocompromised (e.g. if receiving chemotherapy).

Auditable outcomes

Last Updated: Friday, 11 January 2019