Clinical features of acute allergic reactions to peanut and tree nuts in children

Background. Peanut (PN) and tree nut (TN) allergies are potentially life-threatening, rarely outgrown, and appear to be increasing in prevalence. However, there is relatively little reported about the clinical features of acute reactions to these foods and their potential association. Objective. To describe the clinical features of acute reactions during initial and subsequent accidental ingestions of PN and TN among children with a history of at least one acute allergic reaction to these foods. Design. Questionnaire survey, examination, and serologic testing for specific IgE antibody of patients with convincing histories of acute reactions (at least one organ system involved within 60 minutes of ingestion) to PN or TN. Results. A total of 122 patients (63% males; median age, 8 years at time of study) had acute reactions; 68 had reactions only to PN, 20 only to TN, and 34 to both PN and TN. Of those reacting to TN, 34 had reactions to one, 12 to two, and 8 to three or more different TN, the most common being walnut, almond, and pecan. Initial reactions usually occurred at home (median age, 24 months for PN and 62 months for TN) and were considered to result from a first exposure in 72% of cases. Eighty-nine percent of the reactions involved the skin (urticaria, angioedema), 52% the respiratory tract (wheezing, throat tightness, repetitive coughing, dyspnea), and 32% the gastrointestinal tract (vomiting, diarrhea). Two organ systems were affected in 31% of initial reactions, and all three in 21% of reactions. Thirty-eight of 190 first reactions to PN or TN were treated with epinephrine. Accidental ingestions occurred in 55% of PN-allergic children (average of two accidents per patient with an accidental ingestion) and in 30% of TN-allergic children over a median period of 5.5 years. On average, symptoms after accidental exposure were generally similar to those at initial exposure. Accidents occurred commonly in school but also at home and in restaurants. Modes of accidental ingestion included sharing food, hidden ingredients, cross-contamination, and school craft projects using peanut butter. Eighty-three percent of the children were breastfed, with >90% of the mothers ingesting PN and at least one TN during lactation. Among patients reporting no history of exposure (>60% of patients for each TN), IgE antibodies were found to a particular TN in 50% to 82% of patients and to PN in 100% of patients. Conclusions. Acute allergic reactions to PN occur early in life. PN and TN allergic reactions coexist in one third of PN-allergic patients, frequently occur on first known exposure, and may be life-threatening, requiring emergency treatment. Accidental ingestions are common, occur frequently outside of the home, and often require emergency treatment. Consequently, early diagnosis followed by education on avoidance and treatment measures (including self-administered epinephrine) is imperative

Prevalence of peanut and tree nut allergy in the US determined by a random digit dial telephone survey

Background: Allergy to peanuts and tree nuts (TNs) is one of the leading causes of fatal and near-fatal food-induced allergic reactions. These allergies can be lifelong and appear to be increasing in prevalence. Despite the seriousness of these allergies, the prevalence of peanut and TN allergy in the general population is unknown. Objective: We sought to determine the prevalence of peanut and TN allergy among the general population of the United States. Methods: We used a nationwide, cross-sectional, random digit dial telephone survey with a standardized questionnaire. Results: A total of 4374 households contacted by telephone participated (participation rate, 67%), representing 12,032 individuals. Peanut or TN allergy was self-reported in 164 individuals (1.4%; 95% confidence interval [CI], 1.2%-1.6%) in 151 households (3.5%; 95% CI, 2.9%-4.0%). The prevalence of reported allergy in adults (1.6%) was higher than that found in children under 18 years of age (0.6%). In 131 individuals, details of the reactions were obtained. When applying criteria requiring reactions to be typical of IgE-mediated reactions (hives, angioedema, wheezing, throat tightness, vomiting, and diarrhea) within an hour of ingestion, 10% of these subjects were excluded. Among the remaining 118 subjects, allergic reactions involved 1 organ system (skin, respiratory, or gastrointestinal systems) in 50 subjects, 2 in 45 subjects, and all 3 in 23 subjects. Forty-five percent of these 118 respondents reported more than 5 lifetime reactions. Only 53% of these 118 subjects ever saw a physician for the allergic reaction, and only 7% had self-injectable epinephrine available at the time of the interview. The prevalence of peanut and TN allergy was adjusted by assuming that 10% of the remaining 33 subjects without a description of their reactions would also be excluded and correcting for a 7% false-positive rate for the survey instrument. A final “corrected” prevalence estimate of 1.1% (95% CI, 1.0%-1.4%) was obtained. Conclusions: Peanut and/or TN allergy affects approximately 1.1% of the general population, or about 3 million Americans, representing a significant health concern. Despite the severity of reactions, about half of the subjects never sought an evaluation by a physician, and only a few had epinephrine available for emergency use

Effects of early nutritional interventions on the development of atopic disease in infants and children: The role of maternal dietary restriction, breastfeeding, timing of introduction of complementary foods, and hydrolyzed formulas

This clinical report reviews the nutritional options during pregnancy, lactation, and the first year of life that may affect the development of atopic disease (atopic dermatitis, asthma, food allergy) in early life. It replaces an earlier policy statement from the American Academy of Pediatrics that addressed the use of hypoallergenic infant formulas and included provisional recommendations for dietary management for the prevention of atopic disease. The documented benefits of nutritional intervention that may prevent or delay the onset of atopic disease are largely limited to infants at high risk of developing allergy (ie, infants with at least 1 first-degree relative [parent or sibling] with allergic disease). Current evidence does not support a major role for maternal dietary restrictions during pregnancy or lactation. There is evidence that breastfeeding for at least 4 months, compared with feeding formula made with intact cow milk protein, prevents or delays the occurrence of atopic dermatitis, cow milk allergy, and wheezing in early childhood. In studies of infants at high risk of atopy and who are not exclusively breastfed for 4 to 6 months, there is modest evidence that the onset of atopic disease may be delayed or prevented by the use of hydrolyzed formulas compared with formula made with intact cow milk protein, particularly for atopic dermatitis. Comparative studies of the various hydrolyzed formulas also indicate that not all formulas have the same protective benefit. There is also little evidence that delaying the timing of the introduction of complementary foods beyond 4 to 6 months of age prevents the occurrence of atopic disease. At present, there are insufficient data to document a protective effect of any dietary intervention beyond 4 to 6 months of age for the development of atopic disease

Impact of Allergic Reactions on Food-Specific IgE Concentrations and Skin Test Results

Although there is concern that food allergic reactions may negatively affect the natural history of food allergy, the impact of reactions on food-specific IgE (sIgE) or skin prick tests is unknown

Long-term treatment with egg oral immunotherapy enhances sustained unresponsiveness that persists after cessation of therapy

We previously reported results of a randomized, placebo-controlled study of egg oral immunotherapy (eOIT), in which 27.5% of subjects achieved sustained unresponsiveness (SU) after 2 years. Here we report results of treatment through 4 years and long-term follow-up

The natural history of egg allergy in an observational cohort

There are few studies on the natural history of egg allergy and most are single site, not longitudinal, and have not identified early predictors of outcomes

The natural history of milk allergy in an observational cohort

There are few studies on the natural history of milk allergy. Most are single-site and not longitudinal, and these have not identified a means for early prediction of outcomes

Sublingual immunotherapy for peanut allergy: Long-term follow-up of a randomized multicenter trial

We previously reported initial results of the first multi-center randomized, double blind, placebo controlled clinical trial of peanut sublingual immunotherapy (SLIT), observing a favorable safety profile associated with modest clinical and immunologic effects in the first year

Sublingual immunotherapy for peanut allergy: A randomized, double-blind, placebo-controlled multicenter trial

There are presently no available therapeutic options for peanut-allergic patients

Oral Immunotherapy for Treatment of Egg Allergy in Children

For egg allergy, dietary avoidance is the only currently approved treatment. We evaluated oral immunotherapy using egg-white powder for the treatment of children with egg allergy