Prior to ordering tests for hepatitis, the physician should consider the patient’s history, age, risk
factors, vaccination status and any available previous hepatitis test results.
It must be recognized that an established infection with one hepatitis virus does not exclude co- or superinfection with other hepatitis viruses or other agents such as cytomegalovirus or Epstein-Barr virus, although such dual infections are considered uncommon.
Other possibilities to be considered include hepatotoxic drugs including herbal medicines.
Risk factors for viral hepatitis include:
• Substance abuse (e.g. injection drug use, snorting cocaine)
• High-risk sexual activity (e.g. men who have sex with men, traumatic sex)
• Multiple sexual partners
• A sexual partner with viral hepatitis
• Travel to high-risk hepatitis endemic areas or exposure during a local outbreak
• Household contact with an infected person especially if personal items (e.g. razors, toothbrushes,
nail clippers) are shared
• Attendance at daycare
• History of a transfusion-dependent illness
• Needle-stick injury or other occupational exposure (e.g. healthcare workers)
• Receipt of blood products prior to 1990
• Newborn of infected mother
• Tattoos and body piercing
• Contaminated food or water (hepatitis A only)
Role of serology in hepatitis management
•Serology involves the study of seroactive substances for the purpose of diagnosis and
management of diseases
•Such substances may include antigens and antibodies.
•The presence and time of detection of these substances are essential in hepatological
Infectology
Hepatitis A
•Anti HAV:
▫Detectable at onset of symptoms (IgM)
▫Persists for lifetime hence not very useful clinically (IgG)
•IgManti HAV indicates recent infection. Could remain +ve4-6months post infection.
Hepatitis B
• Serologic markers include:
▫ Hep B surface antigen (HBsAg)
Detectable in large quantities in serum
Indicates acute infection and high infectivity
Appears in blood late incubation period and disappears within 3-4 wks but may persist up to 6mths
▫ Anti HBs
Indicates past infection with and immunity to HBV (if assoc. with anti HBc), presence of passive antibody from HBIG,or immune response from HBV vaccine
• Hep B core antigen (HBcAg)
• Anti HBc: of 2 types
▫ IgM
Appears after about 2 mths and may persist till 7th mth.
Indicates acute infection
▫ IgG
Indicates chronic infection
• HBe Ag
▫ Circulating form of HBcAg
▫ A marker of viral replication and infectivity
▫ Appears transiently at onset of infection and lasts 1-3mths
▫ Associated with HBV replication and indicates high titre and infectivity of serum
• Anti-HBe
▫ Appears from 10th wek
▫ Presence in serum of HBsAg carrier suggests lower titre of HBV
• Most sensitive test is detection of HBV DNA in serum though not generally required for routine diagnosis
• HCV:
▫ Anti-HCV, for chronic infections
▫ Serum PCR
• HDV:
▫ Anti HDV (IgG & IgM)
• HEV:
▫ Anti HEV
Conclusion
• Viral hepatitis is a common cause of CLD in this environment.
• Healthworkers are particularly at risk of infection
• Understanding the basis for serological investigations of viral hepatitis improves diagnosis, management, prognostication as well as prevention of the disease and its complications.