Hepatitis A, B, C and E in children — branching viva

Opening question

Examiner: Take me through this child. What is the diagnosis, and what is your frame for managing her? [1]

Candidate: The leading diagnosis is acute hepatitis A — a returned traveller with the classic prodrome of fever and nausea, then dark urine and jaundice, transaminases in the thousands and a positive hepatitis A IgM, with a normal INR. My frame is to classify her on the two axes that matter: transmission route and chronicity. Hepatitis A is enteric and acute, so it clears without chronicity. The immediate priority is supportive care and the prevention of secondary spread; the prognostic anchor I watch is the INR, because a normal INR with this picture means severe hepatitis but not liver failure. [1]

Examiner: Why do you frame the four viruses by those two axes? [1]

Candidate: Because the two axes fix the whole approach. Transmission route tells me how the child met the virus — faecal-oral for A and E, blood-borne and perinatal for B and C — which frames the history, the contact tracing and the prevention. Chronicity tells me what happens next — A and E clear, while B and C persist when acquired neonatally. So a single framework, "faecal-oral is A and E, blood-borne and perinatal is B and C, and the chronic divide runs along the same line", organises the whole topic. [1] [6]

Branch 1 — acute hepatitis A and the anicteric child

Examiner: How would you manage this child, and what would you tell the family about spread? [1]

Candidate: Supportive care is the mainstay — fluids, rest, antiemetics, adequate analgesia and nutrition, and avoidance of hepatotoxins and alcohol. For spread, I would trace household and close contacts and offer post-exposure prophylaxis — hepatitis A vaccine, or immunoglobulin for contacts who are immunocompromised or under one year — reinforce hand hygiene, and exclude her from school and food-handling while she is symptomatic. Most children recover fully over weeks. [1]

Examiner: What is the pitfall with hepatitis A in young children specifically? [1]

Candidate: That young children are often anicteric or subclinical. A child under six may have only a febrile vomiting illness with little or no jaundice, so the diagnosis is missed unless the ALT is checked or a contact is traced. That makes them efficient silent spreaders in daycare and households — the classic scenario is an adult recognised with hepatitis A traced back to an asymptomatic child. So a febrile, vomiting child after travel deserves a hepatitis screen even without jaundice. [1]

Branch 2 — the vertically-exposed hepatitis B neonate

Examiner: Move on. A neonate is born to an HBsAg-positive, HBeAg-positive mother with high viral load. Walk me through the prevention pathway. [4]

Candidate: This is the prevention scenario that defines the topic. The baby receives the hepatitis B vaccine AND hepatitis B immunoglobulin within 24 hours of birth, ideally within 12 hours, at separate injection sites. The vaccine induces active immunity and the HBIG gives immediate passive cover during the window before the vaccine response develops. The vaccine series is then completed through infancy, and at nine to twelve months I test the infant for HBsAg and anti-HBs to confirm protection versus chronic carriage. [4] [6]

Examiner: How does maternal tenofovir fit, and why does a neonate become chronic when an adult clears? [6]

Candidate: For a high-viraemic mother, maternal tenofovir in the third trimester suppresses HBV DNA and reduces the residual transmission that immunoprophylaxis alone does not prevent — together they are the hepatitis B elimination backbone. The chronicity question turns on the moment of acquisition: an adult clears hepatitis B in over ninety percent of cases, but a neonate's immature immune system enters an immune-tolerant phase that lets the virus persist, so the majority of infected neonates become chronic carriers. That is why the birth-dose bundle is a never-miss event. [6] [4]

Branch 3 — chronic hepatitis B and the hepatitis C test-and-treat pathway

Examiner: How do you read a hepatitis B serology panel, and what do you do with a chronic-carrier child? [6]

Candidate: I read the panel as a set: HBsAg marks infection; HBeAg and a high HBV DNA mark high infectivity and replication; HBc IgM marks acute infection while total core antibody marks past or chronic exposure; and anti-HBs marks immunity — alone if vaccinated, with core antibody if resolved naturally. For the chronic-carrier child in the immune-tolerant phase with normal ALT, management is surveillance-led: ALT and HBV DNA monitoring, fibrosis assessment, hepatocellular-carcinoma surveillance in high-risk groups, vaccination of contacts, and transition to adult care. Antivirals are withheld until the immune-active phase or fibrosis appears. [6]

Examiner: And hepatitis C — how do you diagnose and treat it in a child? [9]

Candidate: Hepatitis C is confirmed by a detectable HCV RNA — the antibody alone cannot distinguish past from active infection, and in an infant under about eighteen months maternal antibody confounds the serology, so the infant is tested by HCV RNA. The treatment is a pangenotypic direct-acting antiviral regimen, with which cure rates exceed ninety-five percent in children. There is no hepatitis C vaccine or immunoglobulin, so prevention is test-and-treat the mother and treat the child. I also vaccinate against hepatitis A and B to prevent co-infection. [9] [10]

Branch 4 — hepatitis E and pregnancy

Examiner: Tell me about hepatitis E. Why does it earn its danger? [11]

Candidate: Hepatitis E is the most common cause of acute viral hepatitis worldwide, transmitted faecal-orally through contaminated water and endemic across much of Asia, Africa and Central America. In children it is usually mild and self-limited, often subclinical. Its danger is pregnancy: hepatitis E in the third trimester carries a high maternal case-fatality from acute liver failure and adverse foetal outcomes including stillbirth. So a pregnant adolescent returned from an endemic area with acute hepatitis is hepatitis E until proven otherwise, and she is watched closely with early hepatology and obstetric involvement. [11] [12]

Branch 5 — acute liver failure and the INR

Examiner: Finally. A child with acute hepatitis now has an INR of 3.0 and is drowsy. What has happened, and what do you do? [1]

Candidate: This is acute liver failure. The INR measures hepatic synthesis of clotting factors, and a rising INR with encephalopathy means the liver can no longer synthesise and detoxify — regardless of the bilirubin or ALT. The response is the acute liver failure bundle: protect the brain (raise the head, osmotic agents, intubate if severe), correct the glucose with dextrose, correct the coagulation with vitamin K and fresh frozen plasma, give N-acetylcysteine, admit to PICU, and refer early to a liver-transplant centre, because the window for transfer closes as encephalopathy deepens. The lesson is that the INR — not the bilirubin — is the prognostic anchor. [1] [6]

Wrap

Examiner: Summarise the hepatitis stance in one sentence. [1]

Candidate: Place the child on the two axes — transmission route and chronicity — because together they fix the approach: support and contain the enteric viruses A and E, prevent hepatitis B with the birth-dose-and-HBIG bundle within twenty-four hours and maternal tenofovir suppression, test-and-treat hepatitis C with direct-acting antivirals, surveil the chronic carrier, and remember that in the acutely unwell child the INR — not the bilirubin or the ALT — is the prognostic anchor that crosses the threshold to PICU and a liver-transplant centre. [1] [6]