Immunogenicity and safety of hepatitis A vaccine in children with chronic liver disease

BACKGROUND: Acute hepatitis A superimposed on chronic liver disease has been associated with a more severe course of disease and development of fulminant hepatitis. The aim of this study was to evaluate the immunogenicity and safety of an inactivated hepatitis A virus vaccine in children with chronic liver disease. PATIENTS AND METHODS: This was an open, prospective, and controlled trial with 89 anti-HAV negative children between 1 and 16 years of age studied at a pediatric liver disease and transplantation referral center. Inactivated HAV vaccine (Havrix), from GlaxoSmithKline Biologicals containing 720 Elisa units of alum-adsorbed hepatitis A antigen per 0.5 ml dose was used. Thirty-four pediatric patients with chronic liver disease (mean age: 7.0 +/- 4.86 years) and 55 healthy controls (mean age: 4.8 +/- 2.7 years) received two doses of Havrix vaccine in months zero and six. Seroconversion and anti-HAV titers expressed as geometric mean titers (GMT) in mIU/ml were measured at months one and seven, by a modified Hepatitis A virus antibodies (HAVAB) assay. RESULTS: Seroconversion rates at four weeks after primary immunization were 76% and 94% and the GMT 107.77 and 160.77 mIU/ml in the patient and control groups, respectively. One month after second dose the seroconversion rates were 97% and 100% in the groups with GMT of 812.40 and 2,344.90 mIU/ml. Both doses were well tolerated with no significant adverse events observed. Local injection-site symptoms were the most common reactions reported in both groups. CONCLUSION: Although GMTs were significantly lower in children with chronic liver disease compared to healthy controls, the overall seroconversion rates were not different. Hepatitis A virus vaccine was safe, well-tolerated, and immunogenic in children with chronic liver disease.