Authors T. ROUSSEF (1), S. VANDE VELDE (2), R. DE BRUYNE (2), M. VAN WINCKEL (3), P. SCHELSTRAETE (4), S. VAN BIERVLIET (5) / [1] Ghent University Hospital, Gent, Belgium, Pediatrics, [2] Ghent University Hospital, Gent, Belgium, Pediatric Gastroenterology and nutrition, [3] Ghent University Hospital, Gent, Belgium, pediatric Gastroenterology and nutrition, [4] Ghent University Hospital, Gent, Belgium, Pediatric pneumology and infectious diseases, [5] Ghent University hospital, Ghent, Belgium, Pediatric gastroenterology and nutrition Introduction Celiac disease (CD) is an autoimmune disease characterized by immune mediated inflammatory damage of the small intestinal mucosa, precipitated by the ingestion of gluten-containing foods. Nonresponse following Hepatitis B virus (HBV) vaccine in a healthy population is 4-10% and can partially be explained by genetic predisposition, especially Human leukocyte antigen (HLA) DQ2 and DQ8 alleles seem to play a primary role. It is known that more than 95% of celiac patients possess these HLA genotypes. Consequently, a lower immunisation rate after HBV vaccine is seen in celiac patients. Aim The aim of this study is to prospectively map the responses to HBV vaccine in children with CD. We also investigated if there is a relationship between the patients’ responses to HBV vaccination and the dietary compliance. Methods At the moment of annual follow-up, we performed a blood analysis and measured the anti-hepatitis B surface antibodies (antiHBs AB) in children with CD followed at the pediatric gastroenterology department of the Ghent university hospital, between 2015 and 2016. Subjects with antiHBs AB <10 IU/L were considered non-responders. Non-responders were advised to take a single intramuscular HBV vaccine booster. Response was checked at the next annual appointment. Compliance to gluten free diet (GFD) and CD activity were monitored as usual, using serum anti-transglutaminase antibody levels (a-TG AB). The results were compared to the 4-10% non-response reported in literature. Results 71 children with CD were included of which 24% (n=17) were male. The mean age at diagnosis of CD was 6.1 years (range 1–16 years) and 9.5 years (range 3-17 year) at measurement of antiHBs AB. Of the 31 (43.6%) responders to vaccination, 21 (67.7%) showed low response (10-100 IU/L), 8 (25.8%) intermediate response (100-1000IU/L) and 2 (6.5%) a high response (>1000 IU/L). More than half of the patients were non-responders (40 (56.3%)). Until now, for only 13/40 (32.5%) non-responders, antiHBs AB were available after intramuscular revaccination. Of those 53.8% (n=7) acquired immunity after a single HBV booster. The a-TG AB were still positive in 16/71 (22.5%) CD patients. The a-TG AB ranged from 11-392 U/mL (normal value <7 U/mL). Ten of them were non-responders. Control antiHBs AB titre after booster vaccination was available for 3/10. At control all had normal a-TG AB and 2/3 became responders. Conclusions Non-responsiveness to HBV vaccination was more frequently found in children with CD compared to the literature reported non-response. Since more than half of the CD patients have an insufficient response to HBV vaccination this should be checked. A single booster injection was able to induce a response in more than 50% of patients. Furthermore, compliance to the prescribed GFD may possibly improve the immune response to HBV vaccination in children with CD.
