Tackling the Challenges of Food Allergies
As a researcher and clinician, Amal Assa'ad, MD, willingly takes on challenges so that patients with food allergies may be able to avoid food challenges -- a distasteful way of identifying food allergens -- as well as challenges of living with food allergies. Dr. Assa'ad and colleagues in the Division of Allergy and Immunology at Cincinnati Children's are currently working to identify polymorphisms, differences in the genetic code, which could predict food allergies.
Looking ahead to the next challenge, Dr. Assa'ad expresses hope that "understanding the pathogenesis of food allergies may help us get to novel interventions."
Dr. Assa'ad's interest in food allergies began in her native Egypt, where she earned a medical degree and wrote a master's thesis on food allergies. A visiting fellowship at the University of Texas Health Science Center in San Antonio was followed by a combined residency in medicine and pediatrics at Michigan State University. She and her husband, Raouf Amin, MD, who she had met in medical school in Egypt, moved together to accept positions at Cincinnati Children's, where Dr. Amin is now director of the Division of Pulmonary Medicine.
Potential Clinical Application
"Most people commonly react to foods on the first or second exposure. This is particularly true of peanuts," Dr. Assa'ad explains. "Sensitivity to other foods, such as eggs, can build over time." While these reactions can be less severe, they can be more problematic because eggs are such common components in foods, presenting more possibilities for allergic reactions and symptoms such as rash, sneezing, wheezing and breathing difficulties.
"Whether or not a person will have an allergic reaction to peanuts, milk or any other allergen depends on many factors, including genetics, gender, diet and other environmental factors," Dr. Assa'ad explains. A database being compiled at Cincinnati Children's includes information on these and other factors. "Analyses of data from the first 110 patients have yielded promising results, and analyses of the complete database, now nearing 300 patients, are expected to be completed soon.
"Locating polymorphisms that put a person at risk of developing particular food allergies could have direct clinical applications," Dr. Assa'ad says. "For example, if one child in a family suffered from an allergy to milk, other children born into that family could be genetically tested at birth to see if they also had a predisposition for a milk allergy. If the allergic reaction was likely to be severe, the parents would know that the child should avoid milk." This could spare the child from suffering severe allergic reactions and from being subjected to food challenges and other tests. "Previous analyses seem to find common genotypes in individuals having allergic reactions to cow's milk," Dr. Assa'ad notes.
Painting a Complete Picture
Accepting the challenge of developing effective therapies for hypereosinophilic syndrome, Dr. Assa'ad is working with colleagues in her division, as well as in the Division of Gastroenterology and the Division of Pathology and Laboratory Medicine. "While an overproduction of eosinophils is most commonly caused by an allergic reaction and treated by steroids, the uncontrolled multiplication of eosinophils that characterize hypereosinophilic syndrome is difficult to treat and steroids often become ineffective," Dr. Assa'ad explains. "The challenge is to stop the excessive overproduction of these white blood cells before they attack and harm the lungs, heart and gastrointestinal tract." The research team at Cincinnati Children's is having positive results using anti-IL-5 therapy to block the eosinophil growth factor interleukin-5 (IL-5) in young patients.
The investigators are collaborating on genetic and tissue analysis and identifying a clinical phenotype to "paint the whole picture for the general practitioner of just what hypereosinophilic syndrome is and what it does," Dr. Assa'ad says.
Dr. Assa'ad is associate professor of pediatrics in the Division of Allergy and Immunology. She is co-author of an article on the association of polymorphisms with asthma and food hypersensitivity that was published in the Journal of Allergy and Clinical Immunology (112[2]:438-444, 2003).
