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LONDON (Reuters Health) – Liver grafts from donors with resolved hepatitis B virus (HBV) infection appear to be suitable for recipients who have been effectively vaccinated against HBV and for those who receive immunoprophylaxis after transplantation, French researchers have determined.

In a review of 315 liver transplants performed at Hopital Paul Brousse, Universite Paris-Sud in Villejuif, Dr. Anne-Marie Roque-Afonso and colleagues identified 22 patients (7%) who received allografts from donors with evidence of resolved HBV infection: serology negative for the hepatitis B surface antigen (HBsAg) and positive for anti-core antibodies (anti-HBc).

Four of the 22 patients tested positive for HBsAg before transplantation and received high-dose immunoprophylaxis with hepatitis B immunoglobulin (HBIG) after transplantation, without other antiviral drugs. The three survivors remained HBsAg-negative after receiving an anti-HBc-positive liver graft, the authors report in the January issue of Gut.

In contrast, of four patients who received no HBIG prophylaxis because they were HBV-naive prior to transplantation, all developed HBV infection within 15 months of receiving an anti-HBc-positive liver graft.

Two other patients received no HBIG prophylaxis because they had been vaccinated against HBV and were anti-HBs-positive. They did not develop HBV infection, which suggests, Dr. David Mutimer states in an editorial, "that anti-HBc-positive livers may be suitably placed (without the need for prophylaxis) in recipients who have serological evidence of HBV immunity."

The 12 remaining patients underwent transplantation after July 1998, when according to a new hospital protocol all HBsAg-negative liver recipients received a less stringent regimen of HBIG regardless of their pretransplant anti-HBs status. This group included five HBV-naive patients, four with natural immunity and three with vaccine immunity.

The only patient who developed HBV infection was one of the HBV-naive patients, apparently because of a surveillance failure, the researchers explain. They conclude that "circulating anti-HBs antibodies, without additional antiviral therapy, appear to control HBV replication in recipients of previously infected liver grafts."

But Dr. Mutimer, who is at Queen Elizabeth Hospital, Birmingham, UK, argues that it "cannot be determined" whether HBIG prophylaxis contributed to the positive outcomes of the four patients with natural immunity and the three with vaccine immunity. "For these recipients, immunoprophylaxis may represent an unnecessary and costly addition to their care," he writes.

Citing recent studies of successful lamivudine prophylaxis in this setting, Dr. Mutimer concludes that "for the HBsAg-negative recipient of the anti-HBc-positive liver, it appears that pretransplant immunity to HBV, immunoprophylaxis, or lamivudine (or combinations) significantly reduce the risk of de novo infection. Probably, and despite the fact that conclusive efficacy data are scarce, lamivudine without immunoprophylaxis will be preferred by many transplant units."