Effectiveness of hepatitis A immunisation after paediatric liver transplantation: A retrospective observational analysis.

Abstract

This retrospective study aimed to investigate the response to hepatitis A virus (HAV) immunisation following liver transplantation. We analysed, 234 vaccination records of 284 children who underwent liver transplantation between January 2003 and July 2021, including annual serological results. Of the 120 HAV-naïve patients, approximately 71% and 83% showed seroconversion after receiving one and two vaccine doses, respectively. The third dose increased the seroconversion rate to 93%. In multivariable logistic regression analysis, the number of vaccine doses and age at first vaccine dose were independently associated with seroconversion. In contrast, additional immunosuppression with mycophenolate mofetil (MMF) was negatively associated with seroconversion. In Cox regression analysis of all 96 seroconverted children, younger age at first vaccination and additional immunosuppression with either MMF or prednisolone were identified as independent risk factors for the early loss of HAV immunity. In summary, HAV immunisation with the three-dose vaccination series is recommended for paediatric liver transplant recipients. Antibody testing and booster vaccinations, if necessary, are recommended, especially for those living in endemic areas or with additional immunosuppressive treatments.