The paper by Roque-Afonso et al in this issue of Gut¹ describes the outcome of recipients following transplantation of livers from organ donors who have detectable antibody to the hepatitis B virus (HBV) core antigen (HBc) but undetectable serum hepatitis B surface antigen (anti-HBc positive, HBsAg negative) (see 95). Serum anti-HBc positivity simply confirms exposure to HBV. Its presence in the absence of serum HBsAg identifies the patient with resolved infection. Frequently, antibodies to HBsAg (anti-HBs) will be absent, fading in titre for many patients from the time of acute infection. Thus the patient with a past resolved HBV infection will be anti-HBc positive and HBsAg negative, and anti-HBs may or may not be present. Irrespective of the anti-HBs status of the donor, it is known that the use of anti-HBc positive (HBsAg negative) donor livers will transmit HBV to the recipient and will establish chronic infection and graft damage.^2–5 This is termed de novo HBV infection. Occasionally, aggressive infection with graft failure and patient death may be observed.⁶ In general, the other organs of the anti-HBc positive donor can be used with little risk of de novo infection to the …