Mass population screening for celiac disease in children: the experience in Republic of San Marino from 1993 to 2009

BACKGROUND Prevalence of celiac disease in developed countries is assessed about 1:100-1:150. The real prevalence is unknown because mass screenings are expensive and difficult to organize. Moreover celiac disease can affect people at every age and studies on asymptomatic subjects at different ages are not comparable. In this study we wanted to know the real prevalence of celiac disease in children in the Republic of San Marino. We also analysed concordance of different tests used and costs of mass screening. METHODS The study started in 1993. From 1993 to 1997 children aged 6, 10 and 14 were screened. Since 1997 only children aged 6 were monitored, in order to have a homogeneous population. In fact, every child born since 1980 was taken into account. Children were recruited by classroom lists of students for general paediatric examination. Until 2005 the screening test was based on dosage of antibodies anti-gliadin (AGA) IgA and IgG on venous blood. Since 2006 these tests were replaced by anti-transglutaminase IgA antibodies (ATTG). Anti-endomysial antibodies (EMA) were performed if result of any between either AGA or ATTG tests was positive or borderline; if EMA was positive, then an endoscopy with histological examination was performed to confirm the final diagnosis. RESULTS Attendance to paediatric examination was 96%, submission to blood test was 87%. 42 on 5092 (0,8%; 1:125) children resulted affected by celiac disease. Histology always confirmed diagnosis by serology except for two cases. AGA test (until 2005) yielded 28 on 4304 (0,7% 1:143); ATTG test (since 2006) revealed 14 positive cases on 788 (1,8%; 1:55) leading to a larger percentage of diagnosis. EMA antibodies always confirmed positivity of ATTG. CONCLUSIONS Prevalence of celiac disease in children of Republic of San Marino is comparable to other North-European Countries. Sensitivity of ATTG proved much higher than that of anti-gliadin antibodies. Concordance between ATTG and EMA was 100%. Concordance between serology and histology was approximately 100%. Cost of screening was yearly about 5000 euros (250 children screened every year).