Hepatitis D

(RNA; Gastro 2019:156;461)

• Transmission: blood or sexual; endemic in Africa & E. Europe. Generally requires host to already have HBV infxn in order to cause co-infection or superinfection; in rare cases (immunosupp s/p liver transplant) can replicate autonomously.

• Natural hx: acute HBV–HDV coinfection resolves in >80% of cases; however, acute HDV superinfection leads to chronic HBV–HDV in most cases (↑ progression to cirrhosis, HCC)

• Dx: ✓ total anti-HDV once in all HBV-infected patients, if antibody ⊕, confirm w/ HDV RNA