Coeliac disease: is it time for mass screening?

Screening studies indicate a prevalence of coeliac disease (CD) of up to 1% in populations of European ancestry, yet the majority of cases remain undiagnosed. Serological markers for CD now available have high sensitivity and specificity, offering the option of mass population screening. The principles of disease screening as set out by Wilson and Jugner can be applied to CD to predict whether this is appropriate. CD is an important health problem for the individual and the community because of high prevalence, associated specific and non-specific morbidity, and long-term complications of which the most important are gut malignancy and osteoporosis. However, recent studies indicate that the prevalence of malignancy and the health impact of osteoporosis are much less than previously supposed, so the prophylactic benefits of early diagnosis through screening may be low. While CD has an accepted and effective treatment, dietary gluten exclusion, this is difficult for the individual and asymptomatic cases may be poorly motivated to comply. Diagnosis of CD is by histological confirmation on duodenal biopsy. We now recognise milder degrees of gluten sensitive enteropathy without villous atrophy (Marsh I, II lesions) and the benefits to the individual by identifying these early lesions through screening is unknown: whether to treat such individuals needs to be agreed before programmes commence. Screening with serum antibodies is relatively non-invasive but may have to be repeated during each individual's lifetime. HLA typing beforehand to identify the 30% of the population with DQ2 or DQ8, who are at potential risk of CD, will allow one-off exclusion of a large percentage of the population but like all genetic testing has ethical implications. The economic costs of screening and treatment versus morbidity prevented have not been calculated.