Tehran University Medical Journal

Background: Food allergy is one of the most important among other allergic diseases. Although it is less prevalent in adult but in infants it’s prevalence was reported as much as 8 percent. In part, wheat is one of the six main food allergens in infant and in other part there is extensive cross reactivity between the cereals. Therefore the aim of this study is selection of the best food substitute for wheat among other cereals. Materials and Methods: 24 patients with definitive diagnosis of type one hypersensitivity reaction to wheat were entered in this study. Skin prick test and serum specific IgE (Eliza) with 6 members of cereals family (wheat, barley, oat, Rye-Rice & Corn) were performed for them and open food challenge test was also done with three more available of the cereals (corn, Rice, barley) in our food culture and so comparison between allergenicity of wheat flour and wheat bran with skin prick test were done.

Results: The Skin prick tests (SPTs) were positive in 66.7 percent for Barley, 100 percent for wheat bran and 80-100 percent for other cereals. The results of specific IgE for wheat, Barley were positive in 94.5 percent, 68 percent, 39 percent of patients respectively and the results for other cereals were positive in less than 11 percent of cases. The results of food challenge test, for barley were positive in 60 percent of cases and for Rice and Corn were negative in all cases.

Conclusion: In the base of food challenge test as the gold standard test, the best food substitute for wheat sensitive patient between other cereals, were Corn and Rice respectively. It is important to emphasis that will be needed to perform oral food challenge in hospital with complete emergency equipment before introducing any other cereals as food substitute for wheat, specially Barley.

Background: Cow's milk protein allergy (CMPA) is the most common food allergy during the first year of life. Strict avoidance of specific foods is the only accepted treatment for food-induced allergic reactions. This is often an unrealistic therapeutic option, since cow's milk is a basic food that is extensively used in infant formula. The recent preliminary experience of oral desensitization to cow's milk by Meglio & Patriarca seems promising. The object of this study was to investigate the desensitization of children with CMPA to cow's milk.

Methods: All the patients referred to the Allergology Department of the Children's Medical Center Hospital, Tehran from March 2004 to November 2005 suspected to have CMPA were evaluated. The patients were included in the intervention or control groups of the study. For the intervention group, Meglio's protocol was performed. We observed and examined the control group for at least 6 months. Eventually both groups were reevaluated for the symptoms and persistence of positive specific IgE for cow milk proteins.

Results: We enrolled 20 patients for oral desensitization and 13 patients were enrolled in the control group. Both groups were similar with regard to the mean age, sex and clinical symptoms. In 18 (90%) of the intervention subjects, oral desensitization with cow's milk was successfully performed. The entire protocol was completed by 14 (70%) of the intervention subjects. At the end of the six-month observation period, all the patients in the control group were still symptomatic after ingestion of cow's milk. The levels of specific IgE for cow's milk in the intervention group decreased significantly, which was not observed in the control group.

Conclusion: We successfully desensitized 90% of our CMPA patients. Considering that all the patients in the control group remained symptomatic after the period of observation and our promising results in oral desensitization with cow's milk, we can safely propose this protocol as a hopeful alternative in the treatment of CMPA. We speculate that oral desensitization to cow's milk does not alter the natural outcome of CMPA, but substantially increases the threshold dose necessary to elicit allergic symptoms.

Background: Plant-origin foods are among the most important sources of food allergic reactions. An increase in the incidence of sesame seed allergy among children and adults has been reported in recent years. The aim of this preliminary study was to investigate the prevalence, importance and clinical manifestations of sesame allergy among Iranian patients.

Methods: In a cross-sectional survey, 250 patients with suspected IgE-mediated food allergies completed a questionnaire and underwent skin prick tests with sesame extract as well as cross-reacting foods (walnut, soya and peanut). Total IgE and sesame-specific IgE levels were measured. Patients with positive skin test reactions and/or IgE specific for sesame without clinical symptoms were considered sensitive to sesame. The patients who also had clinical symptoms with sesame consumption were diagnosed as allergic to sesame.

Results: Of the 250 patients enrolled in this study, 129 were male and 121 female, with a mean age of 11.7 years. The most common food allergens were cow's milk, egg, curry, tomato and sesame. Sesame sensitivity was found in 35 patients (14.1%). Only five patients (2%) had sesame allergy. Sesame-sensitive patients had a significantly higher frequency of positive prick test to cross-reacting foods when compared to non-sensitized patients (p=0.00). The type of symptom was independent of gender and age of the patients, but urticaria and dermatitis-eczema were significantly more frequent in sensitized patients (p=0.008).

Conclusions: This is the first study addressing the prevalence of sesame seed allergy in Iranian population. We found sesame to be a common and important cause of food allergy. The panel of foods recommended for use in diagnostic allergy tests should be adjusted.