Inflammatory Bowel Disease, Irritable Bowel Syndrome, or What?: A Challenge to the Functional–Organic Dichotomy

Many patients with inflammatory bowel disease (IBD) in clinical remission continue to have symptoms of pain and diarrhea despite minimal or no ongoing inflammation. These patients may be considered to have an overlap of IBD and irritable bowel syndrome (IBD-IBS). In this month's Journal, a proposal is made that continued symptoms in patients with elevated calprotectin, a marker of inflammation, is related to IBD. We propose an alternate biopsychosocial model whereby mutual effects of peripheral and central factors influence symptom generation in both IBD and IBS. Understanding this model has important implications for treatment of patients with IBD-IBS.