Viral Hepatitis — Viva

Long Case Viva Defence

Candidate's opening statement (model answer)

"Mr Nguyen is a 54-year-old Vietnamese-born man with chronic hepatitis B, never treated, referred with abnormal liver enzymes. He has type 2 diabetes and obesity. His HBsAg is positive, HBeAg negative, HBV DNA 45,000 IU/mL and ALT 118 U/L; transient elastography reads 18 kPa and his platelets are 110." ^[1]

"My main problems are HBeAg-negative immune-active hepatitis B, probable cirrhosis, and his HCC risk. My plan is oral antiviral therapy, 6-monthly ultrasound and AFP surveillance, and testing and vaccination of his household." ^{[1] [3]}

Examiner probing questions and model answers

Q1: "Why is this immune-active rather than immune-tolerant disease?"

"AASLD defines immune-active disease by ALT at least twice the upper limit of normal, or significant histological disease, plus HBV DNA above 2,000 IU/mL if HBeAg negative or above 20,000 IU/mL if HBeAg positive. It sets the ALT upper limit at 35 U/L for men, so his ALT of 118 with HBV DNA of 45,000 meets the HBeAg-negative definition. Immune-tolerant disease is HBeAg positive with high HBV DNA and normal ALT, and AASLD recommends against treating it." ^[1]

Q2: "Which antiviral, and why not peginterferon?"

"AASLD's preferred agents are entecavir, TDF and TAF, with TAF or entecavir considered if there is renal or bone risk. Peg-IFN is contraindicated in decompensated cirrhosis, and AASLD notes that in compensated cirrhosis peg-IFN is not contraindicated but nucleos(t)ide analogues are safer. In cirrhosis with HBV DNA above 2,000 IU/mL, therapy is recommended regardless of ALT." ^[1]

Q3: "He suppresses on treatment. Does HCC surveillance stop?"

"No. AASLD states that antiviral treatment does not eliminate the risk of HCC, and recommends ultrasound with or without AFP every 6 months for HBsAg-positive patients with cirrhosis. The 2023 AASLD HCC guidance recommends ultrasound plus AFP about every 6 months, because semiannual surveillance is associated with earlier tumour stage and better survival than annual surveillance." ^{[1] [3]}

Q4: "His wife is HBsAg negative and anti-HBs negative. What do you do?"

"Household members and sexual partners should be vaccinated if they test negative for HBV serologic markers. AASLD gives the standard schedule as 3 doses at 0, 1 and 6 months. CDC lists household contacts of people with HBV among those to test with the triple panel of HBsAg, anti-HBs and total anti-HBc." ^{[1] [9]}

Q5: "His pregnant niece is HBeAg positive with HBV DNA of 6 million IU/mL. How do you prevent transmission?"

"AASLD recommends HBIG and hepatitis B vaccine for the newborn immediately after delivery, and third-trimester antiviral therapy when HBV DNA is above 200,000 IU/mL. Clinical studies support the safety of these drugs during breastfeeding." ^[1]

"In the Pan trial, TDF 300 mg daily from 30 to 32 weeks until postpartum week 4, with infant immunoprophylaxis, reduced mother-to-child transmission from 18 to 5 percent in the intention-to-treat analysis." ^[2]

Q6: "He turns out to be anti-HDV positive with detectable HDV RNA. What changes?"

"Compared with HBV alone, chronic hepatitis D raises the risk of cirrhosis two- to threefold and HCC three- to sixfold. Nucleoside analogues have shown no direct benefit against HDV, although they are still used for the HBV infection. Bulevirtide, an entry inhibitor, was approved by the European Medicines Agency in 2023 for adults with compensated disease. In MYR301, 48 weeks of bulevirtide 2 mg daily gave the combined virological and ALT response in 45 percent, against 2 percent with no treatment." ^{[5] [10] [4]}