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566 Oral allergy syndrome: A warning?
S188
565
Abstracts
Immunochemical Analysis of Retail Foods Labeled as “May Contain Peanut” or Other Similar Declaration: Implications for Food Allergic Individuals LM Niemann. JJ Hlywka, SL He@ Food Allergy Research and Resource Program, University of Nebraska-Lincoln Food ingredient labeling provides critical information to the food allergic patient. The text on some processed foods contain allergen alert labeling which may read, for example, “May Contain “, “Processed on Shared Equipment with ” or “. The “Manufactured in a Facility That Also Processes interpretation of these statements relative to the amount of allergenic food residues in the product is left to the food allergic consumer. Possible interpretation of these statements can range from the likelihood of allergen presence and therefore complete avoidance of the product, to a perceived nominal risk of inadvertent contamination and consumption of the product. To evaluate the incidence of potentially allergenic residues occurring in food products labeled with allergen alert statements, a market survey of processed packaged foods was conducted for peanut content. The foodstuffs selected for the study had allergen alert labeling statements of “may contain peanut”, “processed on shared equipment that also processes peanut” or “manufactured in a facility that also processes peanut”. Products that listed peanut, peanut flour or peanut traces near the end of the ingredient statement were also included. A total of 70 packaged food products were selected for testing and were purchased at local grocery stores. Samples included cereals, candies, snack foods and bakery products. At least 2 different lot numbers from each product was extracted and analyzed using the Neogen Veratox ELISA for peanut. Peanut was detected in 17% of the products analyzed at concentrations ranging from 1 to 2500 parts per million. Of 22 products tested with “may contain peanut” allergen labeling, 4( 18.2%) had residues in one or more lots. Peanut was detected in 2 of 16( 12.5%) products carrying the label “manufactured on shared equipment”. One of 8 (12.5%) products tested bearing the allergen alert labeling of “manufactured in a facility that also processes peanut” had detectable levels of peanut. Peanut was found in 5 of 24(20.8%) products with peanut listed near the end of the ingredient statement. Peanut allergic patients should be aware that allergen alert labeling may not be a reliable indicator of peanut residue, nor does peanut listed near the end of the ingredient statement infer the level of detectable peanut content. The results of this study are likely to be representative of all allergen alert labeling of this kind, regardless of which allergenic food is involved. It remains prudent for food allergic patients to avoid food products labeled in this manner.
J ALLERGY CLIN IMMUNOL JANUARY 2000
666
Oral Allergy Syndrome: A Warning? Fanny Silviu-Dan. Michelle Melmuon Winnipeg, Manitoba The definition of oral allergy syndrome (OAS) varies greatly between ABPAU in regards to symptom criteria: from strictly localized pnnitus in the oropharynx to complex manifestations of anaphylaxis. It is generally accepted that OAS does not spontaneously improve and there are reports of anaphylaxis to the same foods that caused an initial limited OAS. Despite the potential for systemic symptoms the syndrome is considered self-limited. Strict food avoidance and adrenaline availability are not considered necessary. The prevalence of severe allergic reactions in patients with OAS is largely unknown. We assessed the prevalence of severe IgE mediated reactions in a group of 26 patients with OAS seen in our adult allergy clinic (1995-99). F:M=20:6, mean age 30.7 yrs (range 1952). Oropharyngeal pruritus, rhinoconjunctivitis and throat tightness without shortness-of-breath or tissue swelling were considered part of OAS. Severe throat angioedema interfering with normal breathing, wheezing, generalized urticaria/pruritus were considered manifestations of OAS with anaphylaxis. Epicutaneous tests were done to commercial food allergens and to fresh foods by the prick+prick method. Open challenges were done in selected cases. Histamine and saline were used as positive and negative controls respectively. Skin tests were read at 10 and 15 minutes. Total IgE and specific IgE to various foods were done. Six patients (23. I o/o) had severe anaphylactic reactions for which they required acute treatment. In this group, F:M=5: I, mean age was 28.7 yrs. Three developed anaphylaxis to the initial food that caused the localized OAS symptoms: banana (I), apple, plum, nectarine, cherry, apricot, strawberry, grape and carrot (I) and peanut (1). Three patients described concurrent symptoms of OAS and anaphylaxis to different foods from the same family: OAS to nectarine and peach, anaphylaxis to almonds (2). The one patient who progressed from OAS to anaphylaxis from peanut (as above) has recently developed OAS to canned peas. One patient developed anaphylaxis to kiwi and OAS to pineapple; and years later, OAS to carrot and banana. The interval between OAS and the onset of anaphylaxis to the same food ranged from 2-l 1 years. The mean size of positive skin tests to foods in the patients with anaplylaxis was 4.6 mm (SD 2.84) and in the OAS group with no progession 4.9 mm (SD 2.5). When compared to patients with OAS alone, patients with anaphylaxis were no different with regards to allergic rhinitis/asthma (based on history and positive skin tests to inhalants). Total IgE was 132 III/ml (SEM 52.9). slightly lower than in the OAS group without anaphylaxis: 175.9 IUlml (SEM 44.4). p=O.6. In the studied patient group with confirmed OAS almost a quarter developed life-threatening type reactions. The magnitute of skin test reactions, total IgE and atopic respiratory disease backgrounds offered no basis for predicting severe reactions. OAS may be part of a continuum in the context of food anaphylaxis. This may require reassessment of our recommendations for follow-up and prevention in patients who present with OAS.
565
Abstracts
Immunochemical Analysis of Retail Foods Labeled as “May Contain Peanut” or Other Similar Declaration: Implications for Food Allergic Individuals LM Niemann. JJ Hlywka, SL He@ Food Allergy Research and Resource Program, University of Nebraska-Lincoln Food ingredient labeling provides critical information to the food allergic patient. The text on some processed foods contain allergen alert labeling which may read, for example, “May Contain “, “Processed on Shared Equipment with ” or “. The “Manufactured in a Facility That Also Processes interpretation of these statements relative to the amount of allergenic food residues in the product is left to the food allergic consumer. Possible interpretation of these statements can range from the likelihood of allergen presence and therefore complete avoidance of the product, to a perceived nominal risk of inadvertent contamination and consumption of the product. To evaluate the incidence of potentially allergenic residues occurring in food products labeled with allergen alert statements, a market survey of processed packaged foods was conducted for peanut content. The foodstuffs selected for the study had allergen alert labeling statements of “may contain peanut”, “processed on shared equipment that also processes peanut” or “manufactured in a facility that also processes peanut”. Products that listed peanut, peanut flour or peanut traces near the end of the ingredient statement were also included. A total of 70 packaged food products were selected for testing and were purchased at local grocery stores. Samples included cereals, candies, snack foods and bakery products. At least 2 different lot numbers from each product was extracted and analyzed using the Neogen Veratox ELISA for peanut. Peanut was detected in 17% of the products analyzed at concentrations ranging from 1 to 2500 parts per million. Of 22 products tested with “may contain peanut” allergen labeling, 4( 18.2%) had residues in one or more lots. Peanut was detected in 2 of 16( 12.5%) products carrying the label “manufactured on shared equipment”. One of 8 (12.5%) products tested bearing the allergen alert labeling of “manufactured in a facility that also processes peanut” had detectable levels of peanut. Peanut was found in 5 of 24(20.8%) products with peanut listed near the end of the ingredient statement. Peanut allergic patients should be aware that allergen alert labeling may not be a reliable indicator of peanut residue, nor does peanut listed near the end of the ingredient statement infer the level of detectable peanut content. The results of this study are likely to be representative of all allergen alert labeling of this kind, regardless of which allergenic food is involved. It remains prudent for food allergic patients to avoid food products labeled in this manner.
J ALLERGY CLIN IMMUNOL JANUARY 2000
666
Oral Allergy Syndrome: A Warning? Fanny Silviu-Dan. Michelle Melmuon Winnipeg, Manitoba The definition of oral allergy syndrome (OAS) varies greatly between ABPAU in regards to symptom criteria: from strictly localized pnnitus in the oropharynx to complex manifestations of anaphylaxis. It is generally accepted that OAS does not spontaneously improve and there are reports of anaphylaxis to the same foods that caused an initial limited OAS. Despite the potential for systemic symptoms the syndrome is considered self-limited. Strict food avoidance and adrenaline availability are not considered necessary. The prevalence of severe allergic reactions in patients with OAS is largely unknown. We assessed the prevalence of severe IgE mediated reactions in a group of 26 patients with OAS seen in our adult allergy clinic (1995-99). F:M=20:6, mean age 30.7 yrs (range 1952). Oropharyngeal pruritus, rhinoconjunctivitis and throat tightness without shortness-of-breath or tissue swelling were considered part of OAS. Severe throat angioedema interfering with normal breathing, wheezing, generalized urticaria/pruritus were considered manifestations of OAS with anaphylaxis. Epicutaneous tests were done to commercial food allergens and to fresh foods by the prick+prick method. Open challenges were done in selected cases. Histamine and saline were used as positive and negative controls respectively. Skin tests were read at 10 and 15 minutes. Total IgE and specific IgE to various foods were done. Six patients (23. I o/o) had severe anaphylactic reactions for which they required acute treatment. In this group, F:M=5: I, mean age was 28.7 yrs. Three developed anaphylaxis to the initial food that caused the localized OAS symptoms: banana (I), apple, plum, nectarine, cherry, apricot, strawberry, grape and carrot (I) and peanut (1). Three patients described concurrent symptoms of OAS and anaphylaxis to different foods from the same family: OAS to nectarine and peach, anaphylaxis to almonds (2). The one patient who progressed from OAS to anaphylaxis from peanut (as above) has recently developed OAS to canned peas. One patient developed anaphylaxis to kiwi and OAS to pineapple; and years later, OAS to carrot and banana. The interval between OAS and the onset of anaphylaxis to the same food ranged from 2-l 1 years. The mean size of positive skin tests to foods in the patients with anaplylaxis was 4.6 mm (SD 2.84) and in the OAS group with no progession 4.9 mm (SD 2.5). When compared to patients with OAS alone, patients with anaphylaxis were no different with regards to allergic rhinitis/asthma (based on history and positive skin tests to inhalants). Total IgE was 132 III/ml (SEM 52.9). slightly lower than in the OAS group without anaphylaxis: 175.9 IUlml (SEM 44.4). p=O.6. In the studied patient group with confirmed OAS almost a quarter developed life-threatening type reactions. The magnitute of skin test reactions, total IgE and atopic respiratory disease backgrounds offered no basis for predicting severe reactions. OAS may be part of a continuum in the context of food anaphylaxis. This may require reassessment of our recommendations for follow-up and prevention in patients who present with OAS.