Role of inflammation in pediatric irritable bowel syndrome

Background: IBS affects a large number of children throughout the world and is thought to be the result of disturbed neuroimmune function along with the brain–gut axis. Although the underlying pathophysiologic mechanisms are not clear, the role of low-grade inflammation and mucosal immune activation in IBS symptom generation has become evident also in subsets of pediatric patients. Animal models provided meaningful insight in the causal relationship between abnormal mucosal immune activation and changes in gastrointestinal (GI) sensory-motor function. Likewise, the development of long-standing GI symptoms fulfilling the current criteria for functional GI disorders after infection gastroenteritis and in patients with IBD or celiac disease in remission further supports this hypothesis. Immune activation, its impact on gut sensory-motor function, and potential implications for symptom generation emerged in both children and adults with IBS. Purpose: The aim of this review is to summarize the main evidence on the presence of low-grade inflammation and immune activation in children with IBS, its possible role in symptom generation, and its potential implication for new therapeutic strategies.