Guideline: South African Guideline for the Management of Chronic Hepatitis B: 2013 » Diagnosis
 

Diagnosis

 

In diagnosing chronic hepatitis B, HBV serological markers and HBV DNA levels must be carefully and correctly interpreted, to accurately decide on the phase of the chronic infection so that appropriate management, if required, can be instituted.

 

3.1 HBV serological markers[5,18]

 

HBsAg:

  • General and screening marker of infection
  • First serological marker to appear
  • Surrogate marker for transcriptionally active cccDNA
  • Infection is considered chronic if HBsAg persists for >6 months.

HBeAg:

  • Indicates active replication of virus
  • Absent or low in pre-core or basal core promoter mutations.

Anti-HBc total (HBcAb total):

  • Includes both IgG and IgM HBcAb.

IgG anti-HBc:

  • Most sensitive marker of past exposure to HBV as anti-HBs may be undetectable if HBV infection was acquired in childhood, as is common in SA.

IgM anti-HBc:

  • Marker of acute infection or reactivation
  • Strongly positive in acute infection and possible low positivity in reactivation or flare.[19]

Anti-HBs (HBsAb)

  • Recovery and/or immunity to HBV
  • Detectable after immunity is conferred by HBV vaccination.

Anti-HBe (HBeAb)

  • Usually indicates HBeAg to anti-HBe seroconversion and that the virus is no longer replicating
  • Also present in HBeAg-negative chronic hepatitis, with active replication due to mutants.

 

 

Virological evaluation of HBV infection

 

  • Serum HBV DNA quantification
  • HBV genotype
  • HBV resistance testing.

 

 

Role of HBV DNA testing [18]

 

  • Can differentiate chronic HBeAg-negative disease from the inactive latency state (HBV DNA <2 000 IU/ml)
  • Differentiates between occult hepatitis B (IgG anti-HBc positive, HBV DNA positive, but <200 IU/ml) and resolved infection (IgG anti-HBc positive, anti-HBs positive, HBV DNA negative)
  • Changes in HBV DNA levels used to monitor response to therapy
  • In patients adherent to therapy, increasing HBV DNA levels indicate the emergence of resistant variants
  • HBV DNA levels correlate with disease progression.[20-23]

 

 

Immunological markers, DNA levels and ALT in HBV infection [16,24]

 

See Table 2.

 
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