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Notes: Allergic disease has become a major burden in westernized societies because of a recent rise in its prevalence. Approximately one-third of children suffer from an allergic disease, with the prevalence varying from 15 to 20% for atopic dermatitis, 7 to 10% for asthma and 15 to 20% for allergic rhinitis and conjunctivitis. Despite the increase, it is important not to assume a diagnosis of allergy on the basis of symptoms alone, because allergic and nonallergic conditions may present with similar symptoms. An accurate allergy diagnosis is important in order to treat the patient most appropriately and to potentially prevent or delay the development of allergic disease. A good clinical history is the starting point for accurate allergy diagnosis but is not unequivocal. The European Academy of Allergy and Clinical Immunology has recognized the importance of allergy testing and therefore developed evidence-based recommendations on allergy testing in children. Widespread adherence to these recommendations should improve the quality of care for allergy patients. Cooperation between all healthcare professionals involved in the treatment of allergy patients is also a key to improve our response to the allergy epidemic.

Notes: Numerous studies have addressed the potential of breast-feeding to protect for the development of allergic diseases, and in particular of atopic eczema dermatitis syndrome (AEDS). Although the majority of studies, as well as several meta-analyses, are strongly in favour of breast-feeding, there are some conflicting results and open issues. Furthermore, breast-feeding might be detrimental in a subgroup of young infants with severe early manifestations of AEDS and immunoglobulin E sensitizations to common foods. The aim of this review is not to analyse systematically the current literature, but to suggest a scientifically and clinically based analysis of the benefits of breast-feeding in atopic infants.

Notes: Up to 5% of young children and 2% of adults suffer from food allergy. Among them many have immunoglobulin E (IgE)-mediated food allergy, a condition with potentially fatal allergic reactions. Several studies have addressed possible definite treatment options for food allergy. Immunotherapy, by the oral route or by systemic injections shows promising preliminary results, but current interpretation of these therapeutic options are mostly handicapped by studies with insufficient scientific support, or by severe side-effects. Currently, no studies can support pharmacotherapy. Finally, most promising results were recently published with anti-IgE antibodies in a human trial, or various approaches in a mouse model of food allergy (chinese herbal medicine, specific modulation of the T cell response). Rapidly evolving findings might provide hope for a cure of food allergy in the near future.

Notes: Background: A favorable outcome of anaphylaxis depends on the rapidity of adequate initial management and epinephrine injection. However, few data on the management of anaphylactic reactions are available. The aim of this study was to investigate the management and awareness of anaphylaxis to foods by mean of an Internet-based survey. Methods: Visitors to a website with information on food allergy were invited to join the survey. Items in the survey included the management of anaphylactic reactions, investigations done by the diagnosing physician, and information given to the responder in anticipation of a new anaphylactic reaction. Results: Almost all of the 264 responders were from North America, Europe, Australia, or New Zealand (263/264). The most recent reaction was treated by epinephrine injection in 68.7% (180/262) of cases, or by antihistamines in 14.1% (37/262). Epinephrine was the first treatment for the most severe reaction in only 43.9% (101/230), while antihistamines were given first in 43.5% (100/230). One-third (62/210=29.5%) of the responders diagnosed by a physician received neither a diagnostic blood test nor a skin test. Responders diagnosed by an allergist were more often investigated (91/105=86.7%) than those diagnosed by a pediatrician or an internist (29/44=65.9%), a general practitioner (22/45=48.9%), or another physician (6/16=37.5%) (P〈0.001). Most responders had received instructions on how to deal with a new episode of anaphylaxis (244/263=92.8%). Responders instructed by an allergist were most frequently satisfied with the instructions (115/131=87.8%). Conclusions: A large number of responders did not receive epinephrine for treatment of their most severe, or most recent anaphylactic reaction, and did not undergo allergy tests. The conventional management of anaphylaxis might still be improved.

Notes: Background While the ingestion of small amounts of an offending food can elicit adverse reactions in individuals with IgE-mediated food allergies, little information is known regarding these threshold doses for specific allergenic foods. While low-dose challenge trials have been conducted on an appreciable number of allergic individuals, a variety of different clinical protocols were used making the estimation of the threshold dose very difficult.Objective A roundtable conference was convened to develop a consensus clinical protocol for low-dose challenge trials for the estimation of threshold doses for specific allergenic foods.Methods In May 2002, 20 clinical allergists and other interested parties were invited to participate in a roundtable conference to develop consensus of the key elements of a clinical protocol for low-dose challenge trials.Results A consensus protocol was developed. Patients with convincing histories of food allergies and supporting diagnostic evidence including past challenge trials or high CAP–RAST scores can be enrolled in low-dose challenge trials. Care must be taken with younger patients to assure that they have not outgrown their food allergy. An approach was developed for the medication status of patients entering such trials. Challenge materials must be standardized, for example, partially defatted peanut flour composed of equal amounts of the three major varieties of peanuts (Florunner, Virginia, Spanish). Challenge materials must be appropriately blinded with sensory evaluation used to confirm the adequacy of blinding. A double-blind, placebo-controlled design should be used for low-dose challenge trials. Low-dose challenge trials would begin at doses of 10 μg of the allergenic food and would continue with doses of 100 μg and 1 mg followed by specific higher doses up to 100 mg depending upon the expert judgement of the physician; even higher doses might be applied to assure that the patient is indeed reactive to the particular food. A 30-min time interval would be used between doses, and reactive doses would be expressed as both discrete and cumulative doses. The goal of each challenge would be to develop objective symptoms; trials should not be discontinued on the basis of subjective symptoms only. Statistically, a minimum of 29 patients would be enrolled in low-dose challenge trials for each allergenic food because 0 reactors out of 29 patients at a particular dose allow the conclusion that there is 95% certainty that 90% of allergic individuals will not react to that dose.Conclusion A consensus protocol was developed. Using this protocol, it will be possible to estimate threshold doses for allergenic foods, the lowest amount that elicits mild, objective symptoms in highly sensitive individuals.