“…Alternatively, detailed study of endoscopic tissue and/or blood with new molecular techniques such as mRNA or T cell receptor profiling of the biopsy tissue sites could improve diagnostic yield, and even potentially stratify patients into those who will respond to steroids vs. those who will not. In addition, we did not examine patients for other causes of their symptoms after a negative endoscopic evaluation. For example, in patients with diarrhoea, other aetiologies including small bowel bacterial overgrowth, steatorrhea from pancreatic insufficiency or other infectious causes might be in the differential diagnosis, and an upper endoscopy with duodenal aspiration would be useful for further evaluation.…”