Small Intestinal Bacterial Overgrowth

Abstract

Small intestinal bacterial overgrowth (SIBO) has long been regarded as an important cause of maldigestion and malabsorption in adults, typically in the context of a disturbance in the anatomy and/or physiology of the gastrointestinal tract. SIBO is less well characterised in children but has been associated with a variety of gastrointestinal and even systemic symptoms in several clinical contexts. Certain clinical situations predispose to SIBO in children, including gastric acid hyposecretion, impaired small bowel anatomy, intestinal resection and obstruction, as well as immune dysfunction. More vexed is the proposed association between SIBO and functional gastrointestinal disorders. Associations between SIBO and clinical syndromes are complicated by the challenges that its definition presents. Currently available methodologies suffer from problems with reproducibility and inadequate validation, and an accurate test for the definition of SIBO is needed. It is to be hoped that ever-evolving molecular microbiological techniques will ultimately solve this dilemma. Current treatment remains largely based on the empirical use of antibiotics given that an underlying cause can neither be identified nor corrected in the majority of those afflicted with SIBO.