what causes bacterial overgrowth in small intestine
1 Partial or intermittent obstruction of the small intestine can interfere with the transport of food and bacteria through the small intestine and can result in SIBO. 2  Causes of obstruction leading to SIBO include adhesions-or scarring-from previous surgery and Crohn's disease. Scleroderma damages the intestinal muscles directly. 2  In both cases, abnormal muscular activity in the small intestine allows SIBO to develop. 3  Partial or intermittent obstruction of the small intestine can interfere with the transport of food and bacteria through the small intestine and can result in SIBO.