Background:The immunological response to hepatitis B virus (HBV) vaccine may be suboptimal in children with celiac disease (CD), but the reasons for this are not well defined.Objectives:This study was undertaken to assess the immune response to HBV vaccine in CD children and to explore the possible factors affecting the immune response.Methods:The study population consisted of 3 groups—50 newly diagnosed CD children (group 1), 50 previously diagnosed CD children who were on gluten free diet (GFD) >3 months (group 2), and 100 age and gender matched healthy controls (group 3). The patient characteristics were recorded, and the blood samples were analyzed for HBsAg and anti-HBs titers. The nonresponders were given a booster dose of HBV vaccine and reevaluated after 6 weeks.Results:Positive anti-HBs response was found in 46% in newly diagnosed CD children, 60% in CD children on GFD, and 83% in healthy controls (P< 0.001). The immune response to HBV vaccine in CD children was inferior to that in healthy children (53% vs 83%,P< 0.001). The immune response was found to be significantly affected by age at diagnosis, delay in diagnosis, type of presentation, and compliance to GFD. 44 out of 45 (97.77%) nonresponders from CD group seroconverted after a single booster dose.Conclusion:Early diagnosis and good compliance to GFD may improve the immune response to HBV vaccine in CD children. Single additional booster dose is sufficient to attain optimal immune response.