Editor,—The paper by Nobleet al on capillary dried spot testing for thyroid stimulating hormone measurement is a welcome advance for children with Down's syndrome (DS).1 In reducing the number of venepunctures this patient group needs, we hope that those professionals caring for children with DS do not omit screening for coeliac disease (CD). This condition is equally prevalent and can be as difficult to diagnose as hypothyroidism in DS, as it too is often asymptomatic. Screening for CD should be done by the measurement of antigliadin (AGA) and antiendomysial (EmA) antibodies. Their use as a screening tool is well described in DS with reported prevalence between 3.9% and 16.9%.2-4 Diagnosing CD has important consequences with regard to preventing long term complications and maximising growth potential.4 We would like to highlight that community based testing is also feasible for CD.

A study at our centre investigating the prevalence of coeliac disease in type I diabetics utilised patient self sampling for screening blood samples.5 Blood was drawn into a lithium heparin capillary tube (Monovette, Sarsdedt Ltd, Germany) or onto filter paper. The in house assays used for AGA and EmA were performed on 10–20 ml of serum or plasma; thus capillary samples were more than adequate. This method could easily be incorporated into the “at school” testing described by the authors.

Annual screening for hypothyroidism is recommended.1How often screening should be performed for CD is still a matter of debate. With their proposal to establish a Scottish register of school aged children with Down's syndrome, Noble et al provide the opportunity to perform a Scottish-wide population study for the prevalence of coeliac disease in Down's syndrome and, more importantly, to identify those children who may benefit from early detection. Community based screening with capillary samples would make that a very realistic prospect.