Small Bowel Dysmotilities and Small Bowel Bacterial Overgrowth

Abstract

The main role of the small bowel is nutrient absorption; its mucosa lined with villi increases the contact surface between chyme and intestinal cells. Although the small bowel is the longest segment of the gastrointestinal (GI) tract, its transit takes between 2 and 5 hours and is the shortest of the whole gut. It is the most resilient segment of the GI tract and is thus rarely affected by motility disorders. Small bowel dysmotilities comprise a group of rare disorders affecting the function of any structure of the contractile apparatus from the muscular cells, the intrinsic neurons, or the extrinsic neurons. This review covers the epidemiology, etiology, differential diagnosis, clinical manifestations, physical examination, diagnosis, and treatment of small bowel dysmotilities and bacterial overgrowth. The figure shows GI tract innervations and related pharmacologic treatments. Tables list etiologies of small bowel dysmotilities categorized as primary or secondary causes, treatment strategies related to physiologic abnormalities, and pharmacologic treatments for GI dysmotilities. Key words: chronic intestinal pseudo-obstruction, gastrointestinal dysmotility, motility disorder, small bowel dysmotility, small intestinal bacterial overgrowth This review contains 1 highly rendered figure, 3 tables, and 51 references.