Small Intestinal Bacterial Overgrowth (SIBO)

Small Intestinal Bacterial Overgrowth (SIBO) is a condition where excessive bacteria grow in the small intestine, which normally has relatively few bacteria compared to the large intestine. This overgrowth can interfere with normal digestion and nutrient absorption, leading to symptoms like bloating, diarrhea, and abdominal pain. The small intestine is part of the digestive system responsible for absorbing nutrients from food. When too many bacteria are present, they can consume nutrients and produce gases that cause discomfort. This imbalance can also lead to deficiencies in vitamins and minerals. Overall, SIBO disrupts the normal function of the digestive tract and can significantly affect a person's health.

Small Intestinal Bacterial Overgrowth (SIBO) is defined as an abnormal increase in the number and/or alteration in the type of bacteria in the small intestine, typically exceeding 10^5 colony-forming units per milliliter. It usually results from impaired intestinal motility, anatomical abnormalities, or conditions that reduce gastric acid secretion, allowing colonic-type bacteria to proliferate in the small bowel. The overgrowth leads to malabsorption due to bacterial deconjugation of bile acids and competition for nutrients, causing symptoms such as chronic diarrhea, steatorrhea, and weight loss. SIBO is clinically significant because it can cause nutritional deficiencies, including vitamin B12 deficiency and fat-soluble vitamin malabsorption. It is often associated with underlying disorders like scleroderma, diabetes mellitus, or prior bowel surgery. Diagnosis and management are important to prevent complications and improve quality of life.