Research Roundup: Weight and Allergy, Adults with EE, Milk Allergy & More!
Weight and Allergy
Food-allergic children, particularly those with milk allergy, had lower weight and body mass index (BMI) percentiles than their peers in a study from the University of North Carolina at Chapel Hill. Researchers there looked at weight, height and BMI in 245 food-allergic children who had visited their clinics between 2007 and 2011. Those children with more than two food allergies had lower percentiles for height as well as weight.
“A greater number of food allergies translates into a greater number of dietary restrictions,” explains study co-author Brian Vickery, MD, FAAAAI, in an American Academy of Allergy, Asthma and Immunology (AAAAI) press release. Findings stress “the need for nutritional assessment and intervention to ensure that food allergies do not contribute to any growth delay,” adds study co-author A. Wesley Burks, MD, FAAAAI, in the same news release. The study was presented at the 2013 Annual Meeting of the AAAAI in February.
A separate study presented at AAAAI found injecting epinephrine in the lower rather than upper thigh may be more effective in children who are overweight or obese. Researchers from Royal Manchester Children’s Hospital in England used ultrasound to measure the depth from skin surface to muscle at various points down the thigh and leg of 93 children. In the upper thigh, this depth was greater than the length of the auto-injector needle in a majority of obese children compared to non-obese children (82 versus 25 percent, respectively). In the lower thigh, depth exceeded needle length in just 17 percent of obese and 2 percent of non-obese children.
“Delivering epinephrine into the muscle allows for more rapid absorption and leads to higher blood levels than if it’s injected into the overlying fat,” explains lead author Peter Arkwright, MD, PhD, FAAAAI in a press release. “Considering the rising obesity rates in children, there is concern that epinephrine auto-injectors will not adequately deliver the medication in overweight children who may be experiencing anaphylaxis.”
Probiotics for Celiac Disease
Researchers from Argentina recently reported results from the first clinical trial to examine the effect of a probiotic as the sole treatment for celiac disease. All 22 study participants were in the process of being diagnosed with celiac disease (blood tests were positive) but they hadn’t yet started treatment with the gluten-free diet.
For three weeks, participants were randomly assigned to take the probiotic, B. infantis, or a placebo pill before each meal. Although the probiotic didn’t improve abnormal intestinal permeability, the study’s goal, it appeared to produce some immunologic changes and improve some symptoms. Constipation, reflux and indigestion all improved in the group that took B. infantis. Whether a different dose (they tested only a single-dose regimen), a longer treatment period or a different type or species of probiotics produces better results should be explored in future studies, say researchers. B. infantis was chosen because previous work showed levels are lower in individuals with celiac disease (both those treated and not treated with the gluten-free diet) compared to those without it.
The study took place at the Dr. C Bonorino Udaondo Gastroenterology Hospital in Buenos Aires. Results were published in February in the Journal of Clinical Gastroenterology.
Adults with EE
Food elimination diets work for kids with eosinophilic esophagitis (EE). They also work for adults. In a recent study, nearly three-quarters of adults experienced remission of their EE on a six-food elimination diet.
Food elimination is often used to treat EE, a chronic inflammatory disorder that can cause difficulty swallowing, food impaction and reflux. In the new study, 67 adults with EE cut out wheat, milk, eggs, fish, legumes and soy for six weeks. Those who responded then underwent food challenges to pinpoint specific trigger foods. As with kids, milk, wheat and eggs were the biggest culprits for adults.
Interestingly, food allergy testing (IgE blood and skin tests) didn’t accurately predict EE trigger foods. This suggests EE isn’t an IgE-mediated allergy but rather a delayed hypersensitivity reaction against common, regularly consumed foods, the researchers write. Results also suggest that adult EE is probably the same disease as EE seen in kids, they add.
The study took place at Tomelloso General Hospital in Spain. It was published in February in the Journal of Allergy and Clinical Immunology.
In a second study of adults with EE, researchers from the Royal Adelaide Hospital in Australia say EE may be an important cause of food bolus impaction (food getting stuck in the throat). At their institution, they noted an increase in food impaction over the last 15 years that has coincided with an uptick in EE diagnoses. They recommend that esophageal biopsy—used to diagnose (and monitor) EE—should be performed in all cases of food impaction.
The study was published in February in the Journal of Gastroenterology and Hepatology.
Outgrowing Milk Allergy
Milk allergy is outgrown in approximately 50 percent of children by age five, according to a study by the Consortium of Food Allergy Research (CoFAR), a group established by the National Institute for Allergy and Infectious Disease (NIAID).
At five U.S. study sites, researchers followed 244 milk-allergic children over the first five years of life to assess the natural course of milk allergy. Children were considered milk tolerant if they could ingest typical serving sizes of uncooked milk products (milk, yogurt, ice cream). Three factors were identified as important predictors of developing milk tolerance: initial antibody levels to milk (IgE results), wheal size (from skin prick testing) and the severity of atopic dermatitis, a type of eczema. Using these measurements, researchers developed a web-based calculator to help physicians and parents predict the likelihood of whether or not young children will outgrow milk allergy.
This calculator is available for free at cofargroup.org. Note: Additional studies are still needed to validate this tool. It’s designed for use in children under 15 months of age.
The study was published in January in the Journal of Allergy and Clinical Immunology.
Trace Amounts of Gluten
It’s very difficult to avoid all exposure to gluten, even when strictly adhering to a gluten-free diet. New research indicates that some people with celiac disease (not the majority) are ultra-sensitive to very minute traces of gluten. A team from the University of Maryland’s Center for Celiac Research (now part of Massachusetts General Hospital) asked 17 celiac patients who didn’t get better while following the typical gluten-free diet to eliminate all potential sources of gluten cross-contamination. Even if marked “gluten free,” participants avoided packaged and processed foods, including luncheon meats, flavored dairy products, and frozen, canned or dried fruits and veggies. After three months, 14 participants (82 percent) responded positively with an improvement in symptoms and/or biopsy results. At that point, most (79 percent) were then able to resume the “regular” gluten-free diet.
Researchers say there may be a degree of intestinal recovery, which, once reached, allows patients to tolerate the typical level of gluten cross-contamination in a gluten-free diet. They add that this “gluten contamination elimination diet” may help differentiate exquisitely sensitive celiacs from those with true refractory celiac disease, a serious condition marked by persistent celiac symptoms and villous atrophy.
The study was published in March in BMC Gastroenterology.