Question
A 20-year-old female with history of multiple blood transfusions presents to outpatient department with fever, malaise, nausea vomiting and yellowish discoloration of urine. The blood examination showed elevated bilirubin and liver enzymes and positive for HBs Ag
- (a) What is the probable diagnosis 1 mark(s)
- (b) Write the mode of transmission 3 mark(s)
- (c) Mention the serological markers and their significance 4 mark(s)
- (d) Write the long term complications of the condition. e) Write the laboratory tests used for the diagnosis f) Mention briefly on post exposure prophylaxis. 2 mark(s)
Answer
(a) Probable diagnosis: Hepatitis B virus (HBV) infection — likely a transfusion-transmitted HBV infection, given the history of multiple blood transfusions, jaundice, elevated bilirubin/liver enzymes, and positive HBsAg.
(b) Mode of transmission: Parenteral/blood-borne route — transfusion of infected blood/blood products (as in this patient), use of contaminated needles/syringes (IV drug use, unsafe injection practices), occupational needle-stick exposure; Sexual transmission; and Perinatal (vertical) transmission from an infected mother to her infant during childbirth (the most important route in high-endemicity regions globally).
(c) Serological markers and their significance
- HBsAg (surface antigen) — first marker to appear; indicates current infection (acute or chronic); persistence beyond 6 months defines a chronic carrier state.
- Anti-HBs — indicates recovery and immunity (either from past resolved infection or successful vaccination); its appearance with disappearance of HBsAg signals resolution.
- HBeAg — marker of active viral replication and high infectivity.
- Anti-HBe — appears with seroconversion, generally indicating reduced viral replication/infectivity (though pre-core mutant strains can still replicate despite anti-HBe positivity).
- IgM anti-HBc — indicates recent/acute infection (the “core window” marker, positive even when HBsAg has become undetectable during the window period between disappearance of HBsAg and appearance of anti-HBs).
- IgG anti-HBc — indicates past exposure (either resolved infection or ongoing chronic infection), persists lifelong.
- HBV DNA (viral load) — direct marker of viral replication, used for monitoring and guiding antiviral therapy.
(d) Long-term complications: chronic hepatitis, progressing to cirrhosis, and hepatocellular carcinoma — the classical long-term sequelae of chronic HBV infection.
(e) Laboratory tests for diagnosis: serological markers as above (HBsAg, IgM/IgG anti-HBc, HBeAg/anti-HBe, anti-HBs), HBV DNA quantification (PCR), and liver function tests (elevated ALT/AST, bilirubin) to assess hepatocellular injury; liver biopsy/non-invasive fibrosis assessment (e.g., FibroScan) may be used to stage chronic liver disease.
(f) Post-exposure prophylaxis: for a susceptible individual exposed to HBV (e.g., needle-stick injury, unvaccinated contact), administer Hepatitis B immunoglobulin (HBIG) for immediate passive protection, combined with initiation of the Hepatitis B vaccine series, ideally within 24–48 hours (and no later than 7 days) of exposure — providing both immediate passive protection and long-term active immunity.