Screen for Celiac Disease in Down syndrome

Abstract

Source: Zachor DA, Mroczek-Musulman E, Brown P. Prevalence of celiac disease in Down syndrome in the United States. J Pediatr Gastroenterol Nutr. 2000;31:275–279.Down syndrome (DS) is associated with an increased incidence of a variety of clinical disorders, including Hirschsprung disease, congenital heart disease, anal or duodenal atresia and increased risk of malignancy. Previous studies have suggested an increased prevalence of celiac disease (CD) in DS based upon serologic screening tests.1–4This study examines the prevalence of CD in DS to see whether it would be cost-effective to incorporate screening for CD as part of routine health care of DS patients. Seventy-five patients at the University of Alabama, Birmingham with DS (ages 10 months to 30 years, mean 5.25 years) were screened for antiendomysium antibodies (EMA-IgA), antigliadin antibodies (AGA-IgA, IgG), and total serum IgA levels. All patients had trisomy 21 without mosaicism or translocation. There were 69 Caucasians, 5 African-Americans, and 1 Hispanic patient. All patients with positive endomysium or antigliadin antibodies were referred for small bowel biopsy. None of the patients with DS were IgA deficient. Ten patients (13.3%) were positive for EMA-IgA and half of these were positive for AGA-IgA. Of the 10 patients with positive antibody profiles only 5 had symptoms suggesting possible intestinal involvement. Intestinal biopsies were done on 6/10 patients with a positive EMA-IgA. Five of 6 patients biopsied had findings consistent with CD. Only 1 patient (age 3 years) with positive EMA-IgA had a normal intestinal biopsy. Interestingly, 52% (36/75) had positive AGA-IgG with negative EMA-IgA and AGA-IgA. Because of the poor predictive value of AGA IgG in diagnosing CD2, these patients were not referred for biopsy. Overall, 83% (62/75) of the children with DS had negative screening for CD. The authors conclude that the prevalence of CD in DS in the southeastern United States is 1 in 14 cases and they recommend screening with EMA-IgA and total IgA in all children with DS.Screening with IgA-EMA is highly sensitive and specific in predicting CD in normal populations.1 Using historical data, the presence of CD in DS is at least 35-fold greater than its prevalence in the general population.2 The prevalence of CD in DS in European studies ranges from 10–37%. However, only 10–40% of patients with positive AGA-IgA but negative EMA-IgA results had small intestinal histologic changes consistent with CD.3,5 This report supports the routine screening of all children with DS by measuring total IgA and EMA-IgA at 2 to 3 years of age regardless of symptomology. There is insufficient data to support the conclusion that children with DS should be screened annually after they have had a negative result at their first screening. Should any child with DS develop diarrhea and/or growth failure, malabsorption, abdominal distention, and/or irritability, repeat testing for CD should be performed.Since autoimmune disorders like thyroid disease and diabetes appear to be more common in children with Down syndrome, it is not surprising that celiac disease should also be more prevalent in this population. While it takes a villus to grow a child, it appears that focal absence of villi due to celiac disease may not necessarily result in overt GI symptoms, at least early in life. Therefore, we need to consider serologically testing all children with Down syndrome for this disorder since early treatment might improve growth and/or prevent the symptoms.