Is there a relationship between IBS and small intestinal bacterial overgrowth?
IBS and small intestinal bacterial overgrowth (SIBO) There is a striking similarity between the symptoms of IBS and a condition known as small intestinal bacterial overgrowth (SIBO). The entire gastrointestinal tract, including the small intestine, normally contains bacteria. The number of bacteria is greatest in the colon (at least 1,000,000,000 bacteria per ml of fluid) and much lower in the small intestine (less than 10,000 bacteria per ml of fluid). Moreover, the types of bacteria within the small intestine are different than the types of bacteria within the colon. SIBO refers to a condition in which abnormally large numbers of bacteria (at least 100,000 bacteria per ml of fluid) are present in the small intestine, and the types of bacteria in the small intestine resemble more the bacteria of the colon than the small intestine. The symptoms of SIBO include excess gas, abdominal bloating and distension, diarrhea, and abdominal pain. A small number of patients with SIBO have chronic
