title: Irritable bowel syndrome.
abstract: Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with a high population prevalence. The disorder can be debilitating in some patients, whereas others may have mild or moderate symptoms. The most important single risk factors are female sex, younger age and preceding gastrointestinal infections. Clinical symptoms of IBS include abdominal pain or discomfort, stool irregularities and bloating, as well as other somatic, visceral and psychiatric comorbidities. Currently, the diagnosis of IBS is based on symptoms and the exclusion of other organic diseases, and therapy includes drug treatment of the predominant symptoms, nutrition and psychotherapy. Although the underlying pathogenesis is far from understood, aetiological factors include increased epithelial hyperpermeability, dysbiosis, inflammation, visceral hypersensitivity, epigenetics and genetics, and altered brain-gut interactions. IBS considerably affects quality of life and imposes a profound burden on patients, physicians and the health-care system. The past decade has seen remarkable progress in our understanding of functional bowel disorders such as IBS that will be summarized in this Primer.
authors.affiliation: Department of Internal Medicine VI (Psychosomatic Medicine and Psychotherapy), University Hospital Tübingen, Tübingen, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Enck
authors.affiliation: Wingate Institute of Neurogastroenterology, Barts and London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
authors.forename: Qasim
authors.initials: Q
authors.lastname: Aziz
authors.affiliation: Department of Medical and Surgical Sciences, St. Orsola-Malpighi Hospital, Bologna, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Barbara
authors.affiliation: Wingate Institute of Neurogastroenterology, Barts and London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Farmer
authors.affiliation: Department of Behavioural Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Fukudo
authors.affiliation: Oppenheimer Center for Neurobiology of Stress, Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
authors.forename: Emeran A
authors.initials: EA
authors.lastname: Mayer
authors.affiliation: Department of Human Molecular Genetics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Niesler
authors.affiliation: Lynda K and David M Underwood Center for Digestive Disorders, Division of Gastroenterology and Hepatology, Houston Methodist Hospital, Weill Cornell Medical College, Houston, Texas, USA.
authors.forename: Eamonn M M
authors.initials: EM
authors.lastname: Quigley
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia.
authors.forename: Mirjana
authors.initials: M
authors.lastname: Rajilić-Stojanović
authors.affiliation: Department of Human Biology, Technical University Munich, Freising-Weihenstephan, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schemann
authors.affiliation: Department of Internal Medicine VI (Psychosomatic Medicine and Psychotherapy), University Hospital Tübingen, Tübingen, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Schwille-Kiuntke
authors.affiliation: Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Simren
authors.affiliation: Department of Internal Medicine VI (Psychosomatic Medicine and Psychotherapy), University Hospital Tübingen, Tübingen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Zipfel
authors.affiliation: NIHR Nottingham Digestive Diseases Biomedical Research Unit, University of Nottingham, Nottingham, UK.
authors.forename: Robin C
authors.initials: RC
authors.lastname: Spiller
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology*; D015995:Prevalence; D011788:Quality of Life / Q000523:psychology*; D012307:Risk Factors