Seroprevalence of celiac disease in Belgian children and adolescents

Background : Celiac Disease (CD) has a high prevalence world- wide. Because the disease may be underdiagnosed in Belgium, we wanted to evaluate the seroprevalence of CD in children and ado- lescents. Patients and methods : Serum samples from 1159 apparently healthy children and adolescents aged between 1-19 years, were prospectively collected in 2006 by 15 Belgian diagnostic laborato- ries. In September 2009, all samples were analyzed for human tissue transglutaminase IgA antibodies (IgA tTG) and total IgA lev- els by, respectively a commercial ELISA and immunonephelome- try. Sera, found positive, were assessed by immunofluorescence for the presence of IgA and IgG antiendomysium antibodies (IgA/IgG EMA). In patients with IgA deficiency IgG antibodies against deamidated gliadin peptides (IgG DGP) and IgG antiendomysium antibodies (IgG EMA) were determined. Results : Ten of the 1159 individuals (0.86%) tested positive for IgA tTG. A further 0.86% showed borderline IgA tTG results. In almost two percent (1.98%) of the analyzed samples total IgA lev- els below the lower limit of normal were observed. Four out of eight positive IgA tTG samples tested positive for IgA EMA. All samples with borderline IgA tTG results were negative for IgA EMA. Twenty-six percent (6/23) of the IgA deficient samples showed positive IgG DGP antibodies, but none of those tested pos- itive for IgG EMA. Conclusion : The seroprevalence of IgA tTG in this non-IgA deficient population (n = 1136) in Belgium is 1:114. The combined seroprevalence of IgA tTG and IgA EMA in that same population is 1:284. The seroprevalence based on positive IgA tTG or DPG IgG in ,respectively, non-IgA deficient and IgA deficient subjects is 1:72 (n = 1159). These seroprevalences are similar to those found in neighbouring countries. (Acta gastroenterol. belg., 2012, 75, 325- 330).