Research Roundup: Baked Eggs, Undiagnosed Celiac Disease, Goji Berry Allergy
Tolerating Baked Eggs
Researchers from Mount Sinai School of Medicine recently published data on the first 100 children to undergo oral food challenges with baked egg in their outpatient food allergy clinic, a setting similar to a typical allergist’s office. The team had studied oral food challenges with baked egg previously in a controlled research environment. This time, parents prepared muffins with baked eggs at home according to a specific recipe.
The challenge was conducted by a trained nurse or physician, using food-challenge guidelines developed by the American Academy of Allergy, Asthma and Immunology (AAAAI). Two thirds of the children passed the test, confirming the team’s earlier findings. Of those who didn’t pass, 80 percent had mild reactions treated with antihistamine. Seven patients needed additional oral steroids or a single injection of epinephrine.
According to co-author Anna Nowak-Wegrzyn, MD, “most children with egg allergy can tolerate egg in baked products and the only safe way of finding this out is with a supervised oral food challenge that can be safely done in an allergy office that has experience with food allergic patients.”
Results were published in June in the Journal of Allergy and Clinical Immunology.
Undiagnosed Celiac Disease
Some 83 percent of Americans who have celiac disease still don’t know they have it, according to a collaborative study at the Mayo Clinic in Rochester, Minnesota, and the Centers for Disease Control (CDC). Researchers ran celiac blood panels on 7,798 volunteers who participated in an annual CDC-led health survey. They also asked volunteers if they’d previously been diagnosed with celiac disease and if they were on a gluten-free diet.
The research also revealed that most people who are following a gluten-free diet don’t have a diagnosis of celiac disease. “We need to find out why they’re doing it,” says study co-author and celiac expert Joseph Murray, MD. Testing for celiac disease is strongly recommended before starting a gluten-free diet, he underscores.
The study was published in August in the American Journal of Gastroenterology.
Today we know more about the incidence of lymphoma in patients with celiac disease. Lymphoma, which has previously been linked to celiac, refers to a group of blood cancers that develop in the lymphatic system. In a recent study, researchers from the Celiac Disease Center at Columbia University Medical Center looked back at the records of 1,285 celiac patients they treated over the past 30 years. They found 40 cases of lymphoma—amounting to an incidence about six times higher than expected in the general population—and most had a subtype of the disease known as non-Hodgkin’s lymphoma.
Patients who developed lymphoma were older when their celiac disease was diagnosed (58 versus 43 years old) and more likely to have experienced abdominal pain, diarrhea and/or weight loss. Older patients with these symptoms should be followed more closely for the development of lymphoma, says study co-author and celiac expert Peter HR Green, MD. The risk is small but present, he adds.
The study was published in August in the American Journal of Hematology.
Gluten-Free in EE
The gluten-free diet doesn’t appear to improve eosinophilic esophagitis (EE) in children who have both celiac disease and EE, according to research out of Stollery Children’s Hospital in Edmonton, Alberta. Celiac disease and EE are distinct gastrointestinal disorders but recent research has suggested the two conditions coexist more often than expected.
In the new study, researchers identified 292 children diagnosed with celiac disease and/or EE at their hospital between 2009 and 2011. Nine of these children—4.4 percent of those with celiac disease—also had EE, confirming a higher than anticipated rate of co-occurrence. (Celiac disease affects 1 percent of the general population; EE just 0.04 percent.)
According to researchers, the gluten-free diet was the main treatment for both celiac disease and EE in seven of the nine patients but only one child experienced remission of his EE. More work is needed to gain a better understanding of the association between EE and celiac disease and the role of the gluten-free diet in treatment, they write.
EE is an allergic inflammatory disorder characterized by reflux, vomiting and difficulty swallowing. Treatment often involves elimination diets and medications to reduce inflammation.
The study was published in August in the Canadian Journal of Gastroenterology.
Personal Care Products and Allergy Risk
Researchers from Johns Hopkins Children’s Center have linked exposure to triclosan, a common antibacterial agent used in soaps, mouthwash and toothpaste, with food sensitization and likely food allergy. They found children with the highest levels of triclosan (measured in the youngsters’ urine) had the highest levels of IgE antibodies to food and thereby a higher allergy risk, compared to those with the lowest triclosan levels.
The Hopkins team used urine and blood samples from 860 U.S. children to look at the relationship between exposure to antibacterials and other chemicals (including bisphenol A) in personal care products and allergy risk.
In addition to triclosan, researchers found a link between high levels of parabens and the presence of IgE antibodies to environmental allergens like pollen and pet dander. Parabens are preservatives that have antimicrobial properties and are found in many cosmetics, packaged foods and medications.
Findings support the hygiene hypothesis, i.e., excessive cleanliness interferes with the normal development of the immune system and leads to an increase in allergies. However, the researchers stress that their study is too preliminary to suggest making changes in the use of these products and that it doesn’t prove antibacterial agents cause allergy. More work is planned, including a long-term study in babies exposed to antibacterial agents at birth, following them throughout childhood.
The study was published in August in the Journal of Allergy and Clinical Immunology.
Goji Berry Allergy
Some food-allergic patients should be cautious with goji berries, according to new research from Hospital Marina Baixa in Alicante, Spain. Investigators there looked at skin-prick test results in 30 patients—five of whom had reported an allergic reaction to goji berries while the rest had other plant food allergies. Overall, 77 percent had a positive skin-prick test to goji berries. However, many had never before eaten the fruit. Researchers suspect that cross-reactivity with lipid transfer protein (LTP), a plant food protein, may be responsible. LTP is present in peaches, apples and cherries. Many participants tested positive to both goji berries and LTP.
Goji berries have been used for centuries in traditional Chinese medicine but they’ve only recently made their way into Western diets. Further studies to determine the real importance of goji berries as an allergen are needed, the researchers write. For now, they say the risks of goji berries should be taken into consideration in individuals with food allergy, especially those who are allergic to LTP.
The study was published in the Journal of Investigational Allergology and Clinical Immunology.