More from the 10th International Symposium on Functional Gastrointestinal Disorders
Nearly 400 physicians, researchers, and other health care professionals traveled to Milwaukee for our 10th International Symposium on Functional Gastrointestinal (GI) Disorders in April. Leaders in the GI field presented cutting edge knowledge on functional GI and motility disorders and treatments to other professionals who treat patients with these conditions across the world. In the last issue of Digestive Health Matters we highlighted three topics that were discussed at the meeting – What we Know: An integrated understanding of the functional disorders; Global Epidemiology: How widespread are they; and New Concepts in Pathophysiology of Functional GI Disorders: Causes and mechanisms. Here, we share three more interesting areas that were covered during the three day conference.
Children and Functional GI and Motility Disorders
"Children are not small adults and adults are not big children." Christophe Faure, M.D., Centre Hospitalier Universitaire Sainte-Justine, Montreal, Canada
According to research published in 2009, almost four billion dollars were spent annually in the U.S. just on treatment of childhood constipation. Based on Rome III criteria, 87 percent of these kids had functional constipation.
Early painful experiences, trauma, and social learning can influence symptom presentation of functional gastrointestinal and motility disorders (FGIMDs) in children. Miranda van Tilburg, Ph.D., University of North Carolina, Chapel Hill, NC, reviewed painful experiences during infancy which can impact normal nerve growth and increased risk for developing FGIMDs. During these early years, the part of the central nervous system that controls pain, is maturing. However, inflammation and painful experiences, such as injuries to the GI tract, events associated with abdominal pain, and learned social behaviors, can cause changes to the pain control system.
The good news is that researchers are getting a handle on what is going wrong in the gut and on a cellular level. These insights may offer the basis for treatment strategies. New research studies have found differences in microorganisms in the gut (microbiota) of children with irritable bowel syndrome (IBS). The intestinal flora makeup of kids with diarrhea prominent IBS (IBS-D) and abdominal pain was different than that of kids without functional gastrointestinal conditions.
Difficult to Treat Heartburn
Gastroesophageal reflux disease (GERD) is a condition which develops when the back-flow (reflux) of acidic or non-acidic stomach contents causes troublesome symptoms and/or complications. The most frequent symptom of GERD is heartburn. Proton pump inhibitors (PPIs) are drugs that work by limiting acid secretion in the stomach. They are often prescribed to treat symptoms of GERD.
But why do some people still experience persistent heartburn while taking a PPI? When there is no response to a PPI taken once daily, it may be due to non-erosive reflux disease (not caused by acidic reflux) or functional heartburn. When there’s no response to a PPI taken twice daily, it is probably functional heartburn.
"There are various underlying mechanisms that can lead to proton-pump inhibitor failure and some may even overlap in the same patient. The functional heartburn group provides most of the PPI failure (twice daily patients)," notes Ronnie Fass, M.D., MetroHealth Medical Center, Cleveland, OH.
Unfortunately, upper endoscopy (a test to see inside the upper GI tract) has a limited role in evaluating persons who failed PPI once or twice daily. A pH test that measures acidic or non-acidic reflux in the esophagus provides the best information in evaluating individuals with chronically unmanageable heartburn on treatment.
Lifestyle and dietary modifications are the first line of treatment. Other medications may help reduce esophageal pain, including low-dose antidepressants. Acupuncture and cognitive behavioral therapy may also be helpful in controlling the symptoms of heartburn that has not responded to other treatments.
Food Allergies and Sensitivities
"How gluten sensitivity contributes to FGIDs remains unclear but multiple mechanisms are implicated." Shelia E. Crowe, M.D., University of California, San Diego, San Diego, CA
For many IBS patients, food choices provoke symptoms. Research supports an association between symptoms and specific dietary components such as tryptophan and gluten. Too much or too little tryptophan can influence both levels of anxiety and GI symptoms. The link between gluten sensitivity and GI symptoms in classic celiac is very clear. IBS patients may not have celiac disease, but gluten may still induce their IBS symptoms.
Celiac disease can coexist with or even mimic IBS and other FGIMDs for some people. For others, the mechanism of gluten sensitivity in IBS remains unclear. Though we do not have direct evidence, research suggests a link between gluten and IBS symptoms. Scientists found that immunity markers present in gluten sensitivity may not be altered in celiac disease. Australian researchers discovered that a group of white blood cells (macrophages) behaved abnormally after gluten ingestion. They also found that a protein found in gluten called gliadin increased the number of these cells. Putting it all together, they believe that partially digested fragments of gluten trigger this immune response which in turn provokes dysfunction in the gut.