New Insights Into Functional Abdominal Pain and Irritable Bowel Syndrome in Children: A Multidisciplinary Approach
Functional gastrointestinal disorders (FGID) include a combination of chronic or recurrent symptoms not explained by known biochemical or structural abnormalities. They represent a challenging group of conditions that are frequently misdiagnosed in children and are associated with significant morbidity and high health care costs. They account for more than 50% of the consultations in pediatric gastroenterology practice and 2% to 4% of all general pediatric office visits (1). Quality of life in patients with FGID is substantially poorer than in the general population or in those suffering from asthma or migraine (2). Children diagnosed with functional abdominal pain (FAP) or irritable bowel syndrome (IBS) have more abdominal and other somatic pain, functional impairment, and psychiatric symptoms than controls at 5-year follow-up (3), and one third to half of affected children experience persistence of abdominal pain into adulthood. Other studies have suggested an association between childhood functional abdominal pain and long-term comorbidity including depression, anxiety, lifetime psychiatric disorders, social phobia, and somatic complaints (4).
In the last 5 years, interest in the study and recognition of FGID in children has escalated. Careful epidemiological studies have been conducted, diagnostic criteria have been proposed and validated, significant progress has been made in understanding the pathophysiological mechanisms underlying several of these conditions, and more evidence-based treatment approaches have been developed. The importance of a multidisciplinary approach to childhood FGID is now widely recognized, and functional disorders have gone from being conditions with the stigma of “being in the child's head” or that were associated with “nothing being wrong with the child” to entities that, much like migraines or fibromyalgia, are recognized as legitimate disorders with accepted neuroenteric and central nervous system dysfunctions. Despite these promising developments, clearly more research is needed to further advance the science underlying the pathophysiology and treatment of these conditions. An impediment to progress in the field has been the absence of a forum in which experts from different specialties can meet to discuss different aspects of FGID in children and establish an agenda for future research. The need to further study FAP and IBS in children was emphasized by the 2nd World Congress of Pediatric Gastroenterology Working Group for Neurogastroenterology (5). The American Academy of Pediatrics and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) Committee on Abdominal Pain recently recommended to further investigate the presentation and diagnosis of FGID in children (6). The recent publication of the updated Rome criteria with the inclusion for the first time of 2 pediatric committees (7,8) also created momentum for additional studies in this field.
Based on this background, the symposium “New Insights Into Childhood Functional Abdominal Pain and Irritable Bowel Syndrome: A Multidisciplinary Approach” was designed to bring together basic and clinical scientists whose major clinical and research interest relates to the pathophysiology, evaluation, and treatment of childhood FAP, IBS, and related pain syndromes. The symposium was held on October 24, 2007 in Salt Lake City, UT, 1 day before the NASPGHAN annual meeting. It was cosponserd by NASPGHAN and the National Institutes of Health, and received funding from industry, foundations, and nonprofit institutions. The symposium was an unmitigated success, gathering the participation of more than 350 pediatric and adult gastroenterologists, basic scientists, psychologists, and many other pediatric subspecialists. The body of the symposium consisted of presentations focusing on the pathogenesis, diagnostic criteria, natural history, and treatment options as they pertain to pain predominant FGID in children. An innovative aspect included presentations on the evaluation and treatment of children with other pain syndromes unrelated to the gastrointestinal (GI) tract. The symposium provided opportunities for young scientists to participate and interact with established investigators in the field. Finally, the symposium intended to develop a research agenda for collaborative studies to define the pathophysiology and treatment strategies for childhood FAP.
During the symposium the biopsychosocial model was endorsed to provide a framework to integrate the biological and psychosocial components of FGID. The biopsychosocial model assumes that the individual genetic background and early life experiences influence the biological and psychosocial predisposition to symptom development in response to a variety of physiological or noxious stimuli later in life. This response is affected by physical, environmental, and social exposures that influence the patient's attitude toward illness.
The first module of the symposium discussed the basic and pathophysiological mechanisms underlying FGID, including the role of early life events, genetics, and environment. Given that the biopsychosocial model has been adopted by investigators dealing with non-GI functional disorders, such as fibromyalgia, autonomic dysfunction, and migraine, experts from non-GI disciplines were asked to share their experiences in the second module of the symposium. The absence of a consistent biological marker in FGID has led to the development of symptom-based criteria to diagnose these disorders. The third module was dedicated to discussion of the Rome criteria (7–9). Finally, the last didactic module discussed medical, behavioural, and complementary treatment strategies for pediatric FGIDs.
The end of the symposium was dedicated to the discussion of a research agenda and the creation of a pediatric multicenter consortium for the study of FGIDs, and brought together representatives from the National Institutes of Health, industry, and many interested pediatric gastroenterologists. The following summaries provide the current state of knowledge as it was presented at the symposium.
The symposium was sponsored in part by NIH grant 1R130K080536-01 and by NASPGHAN, Nationwide Children's Hospital, PEOS, Procter & Gamble, TAP Pharmaceutica, and the Rome Foundation.
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