Bacterial overgrowth and intestinal microbiome

Abstract

Alterations in the gut microbiome, including bacterial overgrowth and dysbiosis, play a central role in the pathophysiology of short bowel syndrome and intestinal failure. By definition, patients with intestinal failure require TPN due to significant anatomic, mucosal, or motility disturbances. These factors in addition to pharmacologic and systemic comorbidities remodel the intestinal flora, creating a cascade of downstream pathophysiologic and clinical sequelae. The unique relationship between microbiota, epithelial barrier function, and mucosal and systemic inflammatory pathways likely drives a multitude of symptoms in intestinal failure, from intraluminal malabsorptive symptoms to severe extraintestinal complications, including liver disease. At present, diagnostic evaluations including hydrogen breath testing and duodenal aspiration/culture are considered, but may be limited in accuracy and yield. Therefore, antibiotic therapy is commonly used by intestinal rehabilitation centers. Advancements in microbiomics are likely to yield improved understanding of pathogenesis and applicable clinical evaluations that may direct future therapies in this field.