At age 7, 1% of children were IgA-EMA positive and likely therefore to have subclinical coeliac disease, though less than 0.1% were reported to be on a gluten-free diet. The prevalence of coeliac disease in these children is therefore comparable to that in UK adults.5
The benefit of early diagnosis of subclinical coeliac disease remains unproven, but long term follow up of this cohort may help to resolve this. If screening is worth while, it should be started in childhood.
Since ALSPAC is an observational study based on analysis of anonymous samples,3
confirmatory biopsy was not possible. IgA-EMA have however repeatedly been shown to have high sensitivity and specificity for coeliac disease, and in a recent general population study the combination of IgA-EMA and tTG antibodies that we used was associated with diagnostic histological changes in 83% of those subsequently biopsied, with abnormal intestinal γ/δ T-lymphocyte density in a further 12%.2
Our strategy may even miss some affected children, as individuals with high levels of tTG antibodies without IgA-EMA may have coeliac disease.2
Reported clinical features were similar to those in adults with coeliac disease identified by screening. Gastrointestinal symptoms were not prominent, and the excess in girls mirrors that seen in affected adults. The most striking observation was that children with IgA-EMA were shorter by more than 0.76 standard deviation scores and lighter by 0.54 standard deviation scores than antibody negative children matched for date and place of birth. This equates to about 9 months' growth and weight gain in an average child around this age. These features were independent of gastrointestinal symptoms and anaemia and presumably unrelated to malabsorption.
Occult coeliac disease seems to start in childhood, even in those who are subsequently diagnosed as adults. The search for the trigger resulting in the breakdown of immune tolerance to gluten therefore needs to focus on infancy and intrauterine life.