A very commonly and hotly discussed topic in the celiac disease community is the determination of whom to screen for the disease and when. It is widely understood that celiac disease is under-diagnosed, especially since some individuals remain without symptoms for a long period of time. Blanket screening, however, seems inefficient; so where is the sweet spot for testing?
Edwin Liu, MD, et al, sought to hone in on an answer with a study recently published in Gastroenterology. 1,339 children born in the Denver, CO area during the period 1993-2004 were followed. Of those, 1,285 carried susceptibility genotypes for celiac disease and type 1 diabetes; the remaining 54 children were a designated control group. These children were followed for up to 20 years, and were regularly tested for development of tissue transglutaminase autoantibodies (tTGA), a widely accepted marker for celiac disease or celiac disease autoimmunity.
For the purposes of this study, celiac disease autoimmunity was defined as a positive tTGA for two consecutive blood draws at least three months apart, or a single positive blood draw coupled with an intestinal biopsy confirming villous atrophy. This was elevated to a diagnosis of celiac disease for those individuals for whom biopsy showed Marsh 2 or 3 lesions (more significant villous atrophy), or who had especially high tTGA levels for two blood draws. Over the course of the study, all participants who were found to have celiac disease also met criteria for celiac disease autoimmunity.
Of the 1,339 study participants, 112 developed celiac disease autoimmunity, and 66 of those individuals eventually also met criteria for celiac disease. None of the control group children developed celiac disease autoimmunity. Of the children diagnosed with celiac disease, 30% were asymptomatic. A total of 46 children developed autoimmunity that never converted to celiac disease, and in half of those cases the children, upon later testing, were found to no longer show markers for autoimmunity at all.
Interestingly, prevalence of celiac disease by age 15 was found to be 3.1% during this study. This is quite high, compared to previous estimates. The reasons for this bear further investigation, but this suggests an upward trend of celiac disease occurrence in this latest generation of children, with a rate triple that previously seen in the adult population. This study also revealed that disease development continues through childhood and early adolescence, as the rate of occurrence was only 1.6% for this population at age five, and had reached 3.1% by age 15.
The results of this study suggest that screening for celiac disease in children has value well beyond age five, as nearly half of diagnosed participants developed celiac disease markers after that age. There is some controversy in the medical community regarding the overall efficacy of wide range screening, and this study suggests that such screening may, in fact, not be warranted for children without high-risk genotypes[1]. For those who do, however, it would seem that screening is beneficial over the first 10 years of life.
Read the full study here.
[1] The following are considered “high-risk” genotypes for celiac disease:
DR3-DQ2/DR3-DQ2 (DR3-DQA105:01-DQB102:01/DR3-DQA105:01-DQB102:01)
DR3-DQ2/X (DR3-DQA105:01-DQB102:01/X)
DR3-DQ2/DR4-DQ8 (DR3-DQA105:01-DQB102:01/ DR4-DQA103:0X-DQB103:02)
DR4-DQ8/DR4-DQ8 (DR4-DQA103-DQB103:02/ DR4-DQA103-DQB103:02)
DR4-DQ8/X (DR4-DQA103-DQB103:02/X), where X is neither DR3-DQA105:01-DQB102:01 or DR4-DQA103-DQB103:02.
Cumulative Incidence of Celiac Disease in Children and Adolescents