 All duodenal biopsy specimens will be fixed in buffered formalin and embedded in paraffin wax. Standard, 3μm thick sections at three levels will be stained with haematoxylin and eosin and reported routinely. Additionally, biopsies demonstrating increased intraepithelial lymphocytes only changes compatible with but not diagnostic of coeliac disease will be stained with KiRAS or CD4CD8 which are markers for coeliac disease. 