Prevalence and clinical characteristics of celiac disease in Downs syndrome in a US study.

Celiac disease is an autoimmune gastrointestinal disorder characterized by mucosal atrophy of the jejunum on exposure to gluten, a protein found in grains. The purpose of our study was to determine the prevalence of celiac disease in children with Downs syndrome in a U.S.-based Caucasian population. The 97 Downs syndrome children were screened for celiac disease using serum IgA-anti-endomysial antibody testing, which is highly specific and sensitive for the disorder. Children with titers greater than 1:5 (using the IgA endomysial antibody [EMA] test; EMA+) were considered affected. Ten children (10.3%) were EMA+. We examined their HLA DQA1 DQB1 genotype, karyotype, clinical characteristics, and the prevalence of celiac disease in their first-degree relatives. The nine available karyotypes were trisomy 21. Downs syndrome-specific mean height percentile was 64%+/-26% (range <5-99%) and weight percentile was 43%+/-28% (range 5-95%). Presence of diarrhea, constipation, vomiting, and abdominal pain was similar for children with and without celiac disease. Only bloating symptoms were significantly more frequent in those with celiac disease (EMA+). Seven of eight (88%) genotyped EMA+ children had the celiac disease-associated high-risk HLA DQA1*0501 DQB1*0201 genotype as compared with 13/ 80 (16%) of EMA- children. Five of 48 (10%) first-degree relatives of the celiac disease (EMA+) children were EMA+. In conclusion, celiac disease, as diagnosed by positive endomysial antibody tests, has an increased prevalence in children with Downs syndrome in the U.S. as compared with the general population (1/250). Clinical and growth characteristics do not distinguish between children with and without celiac disease. Based on these observations, it is recommended that children with Downs syndrome be screened for celiac disease.