Medical and Research News
A study published recently in the journal JAMA Pediatrics found a 4-fold increased incidence of celiac disease among children with irritable bowel syndrome (IBS), but not in children with other functional abdominal pain conditions. This is similar to a recent finding in adults.
Results showed that 4% of the children with IBS tested positive for celiac disease, compared with 1% or less of those with functional dyspepsia and with functional abdominal pain.
Because it has become routine to test for celiac disease in all children with recurrent abdominal pain, limiting celiac screening only to those with IBS may be beneficial. It may reduce unneeded testing in children who are no more likely than the general population to have celiac disease, and it could reduce the health consequences for children with IBS who also have untreated celiac disease.
Recently JAMA published a review of medical studies about diverticulitis that have been published over the past decade. The review suggests that changes be made in the way the disease is often treated. Diverticulitis occurs when small pouches in the GI tract become infected. The reviewers observed advances in the understanding of diverticulitis, which warrant less frequent use of antibiotics and surgery. Among the findings were that the risk of recurrence of diverticulitis is low, and the risk of abdominal infection decreases with each recurrence.
A study has shown that small intestinal bacterial overgrowth (SIBO) can be somewhat common in those with gastroparesis.
In a study of 740 patients who were tested for SIBO, 39% of those who had gastroparesis tested positive. Overall, no significant difference in gastroparesis symptom severity was seen between positive and negative results in those with gastroparesis, but there was increased severity of bloating and excessive fullness during and after meals.
Many people suffering from celiac disease are interested in potential medications to treat the condition, according to a published survey that measured the impact of celiac disease on a person’s life. Currently, a gluten-free diet is the only treatment for celiac disease.
Survey responses were analyzed from 352 patients with celiac disease. When asked if they would take a medication to treat the condition, interest was highest among men, older respondents, frequent restaurant customers, those dissatisfied with their weight or concerned with the cost of a gluten-free diet, and those with a worse quality of life. Length of time since diagnosis and response to a gluten-free diet did not appear to increase interest in using medication.
Salmonella Gastroenteritis During Childhood is a Risk Factor for Irritable Bowel Syndrome in Adulthood
Based on data collected from a single foodborne Salmonella outbreak, researchers have shown that Salmonella-induced gastroenteritis during childhood (but not adulthood) is a risk factor for IBS. The outbreak, which occurred in 1994 in Bologna, Italy, involved mostly children.
Clinical data were collected and longterm effects were assessed by mailing a questionnaire to 757 subjects, 16 years after the outbreak (when all of children were adults).
The prevalence of IBS was higher in individuals exposed to Salmonella as children, but not as adults, compared with controls. Preventive measures early in life may help reduce the risk of IBS in adulthood.
A group of researchers studying a specific genetic defect concluded that about 2% of people with IBS carry a mutation in the SCN5A gene. This defect affects a mechanism involved with maintaining normal gastrointestinal motility. The research is in early stages, but the results of this study give researchers hope of finding new therapies for this subset of people with IBS.
This work was supported by grants from the NIH, Mayo Clinic, and the Swedish Research Council.
A randomized controlled trial examined the effect of an experimental diet in people with diabetic gastroparesis, and found that a small-particle size diet may relieve upper GI symptoms.
Dietary restriction is required to treat both gastroparesis and diabetes. This study tested a usual diet for diabetes versus a nutritionally identical experimental diet, which differed regarding the particle size of the food. This was described as food that was "easy to mash with a fork into small particle size." Foods with husks or peels; seeds and grains; or poorly digestible particles such as meat, raw vegetables, and pasta were excluded.
GI symptoms such as nausea/vomiting, early fullness, and bloating were all reduced in those who received the smallparticle diet. Nutrient intake, glycemic control, and quality of life were the same in both diets. Longer studies may be needed to test these findings.
This is the first randomized controlled study of a diet for diabetic gastroparesis. The 20-week study included 56 adults with insulin treated diabetes and gastroparesis.
"Recent findings suggest that IBS is linked to clearly detectable gut microbiota alterations. Additionally, bloating can be related to specific kinds of diet, thus opening up promising paths towards an efficient disease management," says Professor Giovanni Barbara (University of Bologna, Italy). This was one of the topics presented at the Gut Microbiota for Health World Summit in Miami, Fla., USA on March 8 and 9, 2014.
"Probably the best example of this interaction is the discovery that IBS symptoms develop in up to 10 percent of previously healthy subjects after a single episode of gastroenteritis caused by an infection through bacterial pathogens, which can severely disrupt the microbiota balance," says Professor Barbara.
Another important factor is nutrition. Studies show that certain foods can induce changes in the microbiota of IBS patients, prolonging and increasing the symptoms, while the gut microbiota of healthy subjects remained stable and unaffected.
A small pilot study may show that some IBS is hereditary, and linked to DNA in the cells of the mother. By analyzing the mitochondrial DNA of patients with IBS, IBD, and healthy controls, scientists found probable maternal inheritance in 17.5% of the people with IBS, compared to only 2% of otherwise healthy people and 0% the people with IBD.
Mitochondria are important structures inside our cells, and in humans are inherited only from the mother. Mitochondrial dysfunction has been implicated in disorders that often co-occur with irritable bowel syndrome, such as migraine, depression, and chronic fatigue syndrome. These findings suggest that about one person in six with IBS could have an IBS subtype related to mitochondrial function, and that further research in this area is warranted.
A small study has demonstrated that magnetic resonance imaging (MRI) technology can reveal anatomical and functional differences between people with GERD and those without. The differences affect the normal way in which the esophageal and gastric (stomach) anatomy acts to prevent reflux.
The findings demonstrate in a non-invasive testing situation that the "functional anatomy" which normally helps provide a barrier to reflux, is altered in people with mild to moderate GERD. This helps to better understand the mechanisms by which reflux is normally prevented, as well as the changes which allow it to occur.
Takeda Pharmaceuticals has announced that they have submitted a new drug application (NDA) in Japan for a new class of drug to treat acid-related disorders. The compound has been assigned the generic name vonoprazan fumarate. It belongs to a new class of acid secretion inhibitors called potassium-competitive acid blockers. They work slightly differently from proton-pump inhibitors (PPIs), which are currently among the most common treatments for these disorders.
The NDA was submitted based on positive results from Phase III clinical trials in Japan, for indications including erosive esophagitis, gastric ulcer, duodenal ulcer, and H. pylori eradication.
Salix Pharmaceuticals is partnering with another company to develop a bowel prep compound that is in the form of a tasteless capsule. Currently, people preparing for abdominal procedures or diagnostic tests such as colonoscopy must drink a bowel prep solution to help cleanse the gastrointestinal tract. Most liquid preparations require drinking a large quantity of the prep which many people find unpleasant to the taste. The RHB-106 preparation is a solid capsule which eliminates any unpleasant taste and could potentially make it easier for people to use.
Researchers led by a group at McMaster University in Canada have discovered a mechanism that helps us better understand how the bowels function. The finding may lead to a better understanding of how to treat people with disorders of nutrient absorption, diarrhea, constipation, and bloating.
Food in the intestine must be propelled along the gut from the stomach down to the colon (a movement referred to as peristalsis), and it also must be mixed to maximize the absorption of nutrients.
The mechanism of peristalsis has previously been demonstrated to be the result of a slow-wave pacemaker generated by special cells in the intestinal walls, called interstitial cells of Cajal (ICCs).
The researchers discovered that the mixing movement is generated by a second pacemaker that interacts with the first. Together, they create back and forth movements that optimize nutrient absorption.
The following medical studies were presented as abstracts at the May 2014 Digestive Disease Week (DDW), a conference for medical professionals. They indicate new findings of possible treatments. However, the data and conclusions should be considered preliminary until the data is published in a peer-reviewed journal.
New data using laboratory models examining the prescription medical food, EnteraGam™, was presented at DDW, demonstrating that the protein mixture in EnteraGam binds and neutralizes two types of toxins from several types of C. difficile, including recently isolated strains which are particularly infectious.
The laboratory based data specifically showed direct binding of immunoglobulins in EnteraGam to each toxin, as well as protection from cell death of cells which are particularly affected by toxins. C. difficile toxins can cause damage to the lining of the intestines, contributing to the symptoms of infection that can range from diarrhea to severe, life-threatening colitis.
A novel drug designed for the treatment of celiac disease reduced both gastrointestinal (GI) and non-GI symptoms in people exposed to gluten, in a randomized placebo-controlled trial presented at DDW.
Larazotide acetate is a first-in-class oral peptide which affects intestinal barrier function and reduces gluten uptake, inhibiting gluten-induced intestinal permeability and inflammation.
Celiac disease, which is triggered by the ingestion of gluten, is managed with a gluten-free diet. However, symptoms often recur as a result of accidental exposure to gluten or not strictly following the diet. Recently published data suggest that 70% of patients continue to be exposed to gluten while on a gluten-free diet. This exposure causes not only GI-related symptoms, but also non-GI symptoms such as headache and tiredness. Larazotide acetate reduced both types of symptoms in this trial.
Larazotide acetate has the potential to be the first pharmacologic treatment for celiac disease and warrants investigation in Phase 3 clinical trials, the study author concluded. The drug has been granted Fast Track status by the U.S. Food and Drug Administration.
The investigational drug RM-131 (relamorelin) significantly improved gastric emptying and vomiting in patients with diabetic gastroparesis in a Phase 2, double-blind study presented at DDW.
Gastric emptying improved by an average of 23 minutes from baseline, and also reduced vomiting episodes and vomiting severity, when taken by twice-daily injection for four weeks. Ghrelin is a hormone produced in the stomach that stimulates gastrointestinal activity. Relamorelin promotes activity of ghrelin.
A study presented at DDW shows that a procedure using a computer-assisted technique where a brush collects a tissue sample (biopsy) may be better at detecting Barrett’s esophagus than the traditional forceps biopsy method. Barrett’s esophagus, a condition marked by cellular changes, is a risk factor for esophageal cancer.
Investigators reviewed data on patients who underwent endoscopy for the evaluation of gastroesophageal reflux disease from 28 community based gastroenterologists. Both brush biopsy samples and forceps biopsy samples were collected on each patient during the same endoscopy procedure.
Forceps biopsy identified Barrett’s esophagus in 377 cases and the computer assisted brush biopsy identified an additional 258 cases, enhancing the detection of Barrett’s esophagus by 68.4%. The authors conclude that this technique, used by community gastroenterologists, may help improve care by better identifying these patients.
A small, short-term diet low in certain types of poorly absorbed and highly gas-forming carbohydrates (FODMAPs) may reduce symptoms in children diagnosed with irritable bowel syndrome (IBS), according to an abstract presented by researchers at DDW. In the nine-day study, children had fewer daily abdominal pain episodes, as well as less bloating and nausea, during the two-day periods on which they ate low-FODMAPs.
Additional studies are underway to further explore the efficacy of low-FODMAP diets and how they interact with other existing factors.
FODMAPs are found in many fruits, vegetables, dairy products, and sweeteners.
Research summaries presented at DDW reviewed data from Phase 3 and Phase 3b clinical trials of linaclotide (Linzess) in people with chronic constipation.
New data from a Phase 3b trial showed that linaclotide improved bowel and abdominal symptoms, in those with chronic idiopathic constipation with prominent bloating at the start of the trials.
Data from two Phase 3 trials was pooled to review the relationship between chronic constipation symptoms, and health-related quality of life (HRQOL). The study concluded that reduction in bloating was more strongly associated with improved HRQOL than other chronic constipation symptoms.