G270 DQ typing for down syndrome should be part of routine surveillance. (25th October 2020) - Yates, J
Abstract : Aims: Down Syndrome (DS) is associated with increased prevalence of coeliac disease (CD). Recent meta-analysis estimates prevalence at 5.8%. 1 The DS Medical Interest Group (DSMIG), does not recommend routine screening, despite guidance from the European Society of Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN). 2 HLA-DQ haplotyping for CD has been offered for the last 3 years. 3 Method: Children with DS identified from Support Needs System (SNS). In 2016, families were invited for HLA DQ haplotyping for DQ2.2 2.5& 8 (and coeliac serology). Subsequently, families invited though discussions in clinic. Children with positive typing are offered coeliac serology every 3 years (or sooner if symptomatic). Results: 35 (17 female/18 male) DS children were identified. (1 child excluded as already diagnosed). 28 (76%) children have been tested. 12 (39%) had negative haplotypes, excluding them from life-long screening. 16 (57%), tested positive (table 1 ). Mean age at testing was 7 years. 5 (31%) had positive coeliac serology. Of these, 3 (60%) had CD, one from each haplotype. 2 had positive serology at initial screening with positive biopsies and 1 diagnosed when rescreened. All were clinically asymptomatic. The other 2 were both DQ2.5: 1 had negative biopsy for CD but had gastritis and 1 refused biopsy. Both are being clinically monitored. Conclusions: Prevalence of CD in DS in this area is currently 11% using HLA-DQ haplotyping and 3 yearly screening. All were asymptomatic at diagnosis and all successfully started on to gluten-free diet. DQ typing is effective in excluding DS children from ongoing screening. 1 3 Positive haplotyping is effective in educating parents about potential CD and risk stratification. 4 5 Three yearly coeliac serology will be performed alongside annual thyroid function tests. DQ typing can be performed at the earliest opportunity in any child prior to gluten exposure and should be a standard of care in the UK. It reduces the burden of testing for the child and the financial cost of repeated serology when symptomatic as CD is very unlikely. References: Prevalence of Coeliac Disease in patients with Down Syndrome: A meta-analysis. Oncotarget 2018.Vol; 9 (no.4) 5387–5396. Joint BSPGHANand Coeliac UK guidelines for the diagnosis and management of coeliac disease in children Murch S, Jenkins H, Auth M, et al. Arch Dis Child 2013;98(10):806–11. DQ typing is effective in Coeliac Disease screening in children and young people with Down Syndrome in South East Scotland. C. Sumner, et al. Archives of disease in childhood 2016 310863.358 Appropriate Clinical use of human leukocyte antigen typing for coeliac disease: an Australasian perspective. Tye-Diet, et al. Internal Medicine Journal 45 ( 2015) 441–450 Impact on parents of HLA DQ2/DQ8 genotyping in healthy children for coeliac families. Wessels, et al. European Journal of Human Genetics ( 2015) 23, 405–408.