A 55 year old man with coeliac disease presents with ongoing diarrhoea and weight loss despite a strict gluten free diet. What is the most appropriate next step in investigation?ACheck for IgA deficiency and consider repeat biopsy to exclude refractory coeliac disease or other pathologyBReassure that symptoms are functionalCStart long term steroids empiricallyDAdvise stopping the gluten free dietEOnly prescribe loperamide without further testsCheck my answer