Abstract

Traditionally, small intestinal bacterial overgrowth (SIBO) has been characterized by symptoms of diarrhea, bloating, and sometimes signs of malabsorption. It has been defined as >105 cfu/ml of bacteria in aspirates obtained from the small intestine (1). This condition has typically been diagnosed in patients with readily identifiable alterations in small bowel function which predispose patients to SIBO (e.g. resected ileocecal valve, small intestinal hypomotility and possibly hypochlorhydria). Recently however, this clinical paradigm has been challenged by new theories about the etiology of irritable bowel syndrome (IBS) and has lead to renewed scrutiny of the tests employed to diagnose this condition and controversy concerning the use of antibiotics to treat IBS for suspected SIBO.