Objective: Vaccination against hepatitis A (HAV) has been shown to be safe and effective in healthy subjects and in patients with chronic liver disease (CLD). The safety and efficacy of HAV vaccines in liver transplant (OLT) recipients have not been established. The objective of this study is to assess the safety and efficacy of inactivated hepatitis A vaccine in OLT recipients.
Methods: Thirty-seven HAV seronegative OLT recipients were enrolled. Patients received two doses of vaccine 6 months apart. Postvaccination IgG anti-HAV were determined at 1, 6, and 7 months after the first vaccine dose. Side effects were monitored for 3 days after each vaccination shot. An unvaccinated control group (45 patients) was followed for evidence of seroconversion. Seroconversion rate was also compared with those reported in healthy patients and in patients with chronic liver disease.
Results: Testing was available for all the cases at 1 month, and for 26 and 23 patients at 6 and 7 months, respectively. Only 3 of 37 patients (8%) had seroconversion at 1 month. At 6- and 7-month time points, 5 of 26 (19%) and 6 of the 23 (26%) patients had seroconversion, respectively. Vaccine responders had higher total white blood cell count and lymphocyte count and were further out from transplant compared with nonresponders. None of the unvaccinated patients had seroconversion over the follow-up time. Seroconversion rates in OLT recipients were significantly lower than that reported in healthy individuals (P=0.001) or in pre-OLT patients with CLD (P=0.001). All patients tolerated the vaccine well.
Conclusions: HAV vaccination is safe in OLT recipient. Efficacy of HAV vaccination in OLT recipients, as measured by a commercially available enzyme immunoassay, is low and alternative strategies should be developed to improve response rate.