Immediate-type Food Allergy Research Articles

Food Avoidance Diets for Dermatitis.

Food allergy is relatively common in both children and adults, and its prevalence is increasing. Early exposure of food allergens onto skin with an impaired epidermal barrier predisposes to sensitization and prevents the development of oral tolerance. While immediate-type food allergies are well described, less is known about delayed-type food allergies manifesting as dermatitis. This is due, in part, to limitations with current diagnostic testing for delayed-type food allergy, including atopy patch testing. We conducted a systematic review of food avoidance diets in delayed-type food allergies manifesting as dermatitis. While beneficial in some clinical circumstances, avoidance diets should be used with caution in infants and children, as growth impairment and developmental delay may result. Ultimately, dermatitis is highly multifactorial and avoidance diets may not improve symptoms of delayed-type food allergy until combined with other targeted therapies, including restoring balance in the skin microbiome and re-establishing proper skin barrier function.

Food allergen sensitization in young children with typical signs and symptoms of immediate-type food allergies: a comparison between monosensitized and polysensitized children.

PurposeThe clinical interpretation of children sensitized to allergens is challenging, particularly in children with food allergies. We aimed to examine clinical differences between children with monosensitization and those with polysensitization to common food allergens and to determine risk factors for polysensitization in young children <10 years of age with immediate-type food allergies.MethodsThe study included children <10 years of age with signs and symptoms indicative of immediate-type food allergies. Serum total IgE level was measured, and ImmunoCAP analysis for food allergens was performed.ResultsThe mean age of the study subjects was 1.6±1.6 years (75 boys and 51 girls). Thirty-eight children (30.2%) were monosensitized and 88 children (69.8%) were polysensitized. Multivariate logistic regression analysis showed that the development of polysensitization to common food allergens was positively associated with a parental history of allergic rhinitis (adjusted odds ratio [aOR], 6.28; 95% confidence interval [CI], 1.78-22.13; P=0.004), season of birth (summer/fall) (aOR, 3.10; 95% CI, 1.10-8.79; P=0.033), and exclusive breastfeeding in the first 6 months of age (aOR, 3.51; 95% CI, 1.20-10.25; P=0.022).ConclusionWe found significant clinical differences between children with monosensitization and those with polysensitization to common food allergens and identified risk factors for the development of polysensitization in young children with immediate-type food allergies. Clinicians should consider these clinical risk factors when evaluating, counseling, treating, and monitoring young children with food allergies.

Non-IgE-related diagnostic methods (LST, patch test).

Although most food allergy patients have immediate-type reactions, some have delayed-type reactions. Unlike for the detection of food-specific IgE antibody in immediate-type (IgE-mediated) food allergies, only a few tests are currently available to aid in the diagnosis of delayed-type (non-IgE-mediated) food allergies. This chapter summarizes our current understanding of one in vitro test and one in vivo test for non-IgE-mediated food allergies: the lymphocyte stimulation test (LST) and the atopy patch test (APT). Although the LST is not yet standardized, a food protein-specific LST might be a useful tool for diagnosing delayed-type food allergies, and especially those manifesting with gastrointestinal symptoms but not skin symptoms. Various remaining issues - including basophil contamination of the peripheral blood mononuclear cell fraction and lipopolysaccharide contamination of food antigen preparations - are also discussed. The APT uses an epicutaneous patch technique to occlusively apply food antigens to the skin to induce inflammatory reactions at the patch application site. Because the APT shows modest sensitivity and specificity, the clinical benefit of the APT in the diagnosis of food allergies in patients with atopic dermatitis is limited. A position paper on the APT issued by the European Academy of Allergy and Clinical Immunology/Global Allergy and Asthma European Network in 2006 is briefly summarized, and several recent APT-related topics, including APT use for the diagnosis of food protein-induced enterocolitis syndrome, are discussed.

Prevalence of Immediate-Type Food Allergy in Early Childhood in Seoul

PurposeThere are scanty epidemiologic data on the prevalence of food allergy (FA) among preschool children in Asia. We performed this study to determine the prevalence and causative foods of immediate-type FA in early childhood in Korea.MethodsA questionnaire-based, cross-sectional study was performed between September and October 2011. Children aged 0-6 years were recruited from 301 public child care centers in Seoul. Parents were asked to complete a questionnaire on FA. Children with FA were classified into "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" according to the algorithm.ResultsA total of 16,749 children were included in this study. The prevalence of "perceived FA, ever," "immediate-type FA, ever," and "immediate-type FA, current" was 15.1%, 7.0%, and 3.7%, respectively. "Immediate-type FA, current" was reported by 182 (4.9%) out of 3,738 children aged ≤2 years, 262 (3.4%) of 7,648 children aged 3-4 years, and 177 (3.3%) of 5,363 children aged 5-6 years. Hen's egg (126/621) was the most frequent cause as the individual food item, followed by cow's milk (82/621) and peanut (58/621). Among the food groups, fruits (114/621), tree nuts (90/621) and crustaceans (85/621) were the most common offending foods. The three leading causes of food-induced anaphylaxis were hen's egg (22/47), cow's milk (15/47), and peanut (14/47).ConclusionsThe prevalence of immediate-type FA in early childhood is 3.7%, and is higher in younger children. The most common offending foods differed with age.

Evaluation of the adult patient with atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a large impact on quality of life of the patients and their families. In most cases, the diagnosis of AD can easily be made based on (family) history and clinical examination. If necessary, a practical set of diagnostic criteria such as the UK diagnostic criteria can be used. During the diagnostic phase, it is important to pay attention to atopic comorbidity, such as allergic airway disease (allergic asthma and/or rhinitis), allergic eye disease (atopic (kerato) conjunctivitis) and immediate-type food allergy. This will not have direct consequences for the treatment of AD, but may be important for the overall well-being of the patient. Psychological factors, such as family circumstances, work/school performance and lifestyle factors should also be explored. Severity scoring using properly validated scoring lists may not be necessary for the diagnosis, however, is recommended for monitoring therapy. Simple scoring systems, such as TIS and IGA are easy to perform in daily practice. Several flare factors in AD, such as exposure to irritants or UV light, can be identified by history and clinical examination: in individual cases, additional diagnostic tests may sometimes be useful to confirm clinical suspicion. There is only limited evidence that allergen exposure to aeroallergens and/or food allergens influences AD severity. Therefore, routine allergen testing is not necessary for diagnosis and treatment of AD. The decision to perform allergen tests mainly depends on atopic comorbidity.

Prevalence of immediate-type food allergy in Korean schoolchildren: A population-based study

Although the prevalence and causes of food allergy (FA) vary by geographic location, large well-designed epidemiological studies in Asia are lacking. The purpose of this study was to evaluate the prevalence of immediate-type FA in the general population of Korean schoolchildren. A population-based, cross-sectional study was conducted in 2010 using a stratified two-stage cluster-sampling design. In this survey, children aged 6-7 years and 12-13 years were randomly selected, and the presence of FA was determined by a questionnaire survey and assessment of specific IgE. After adjustment for missing data, 3907 children aged 6-7 years and 3975 students aged 12-13 years who completed the questionnaire were included in this study. In children aged 6-7 years, the prevalence of confirmed immediate-type FA was 0.3%, and the prevalence of possible immediate-type FA was 0.3%. By contrast, 0.6 and 1.0% of children aged 12-13 years had confirmed immediate-type FA and possible immediate-type FA, respectively. In 6- to 7-year-old children, egg was the most frequent causative food associated with a confirmed or possible immediate-type FA. In 12- to 13-year-old children, crustaceans were the most frequent cause of confirmed immediate-type FA, and fruit was most frequently involved in possible immediate-type FA. This is the first nationwide population-based study of FA in Korean schoolchildren. Unlike in western countries, the prevalence of immediate-type FA seems to be low. In 12- to 13 year-old children with confirmed immediate-type FA, peanuts/tree nuts are not common causes, whereas crustaceans are frequent triggers.

Prevalence of IgE-mediated Food Allergy in Korean schoolchildren: A Population-based Study

Although the prevalence and causes of food allergy vary by geographic location, large well-designed epidemiological studies in Asia are lacking. The purpose was to evaluate the prevalence of IgE-mediated food allergy in the general population of Korean schoolchildren. A population-based, cross-sectional study was conducted in 2010 using a stratified two-stage cluster-sampling design. In this survey, 4,003 children aged 6-7 years and 4,112 students aged 12-13 years were randomly selected, and the presence of food allergy was determined by a questionnaire survey and assessment of specific IgE. "Probable immediate-type food allergy" was reported in 2.0% of 6-7-year-olds and 3.6% of 12-13-year-olds. In children aged 6-7 years, the prevalence of "confirmed IgE-mediated food allergy" was 0.3%, and the prevalence of "possible IgE-mediated food allergy" was 0.3%. By contrast, 0.6% and 1.0% of children aged 12-13 years had "confirmed IgE-mediated food allergy" and "possible IgE-mediated food allergy," respectively. In 6-7-year-old children, egg was the most frequent causative food associated with a "confirmed" or "possible IgE-mediated food allergy." In 12-13-year-old children, crustaceans were the most frequent cause of "confirmed IgE-mediated food allergy," and fruit was most frequently involved in "possible IgE-mediated food allergy." This is the first nationwide population-based study of food allergy in Korean schoolchildren. Unlike in Western countries, the prevalence of IgE-mediated food allergy seems to be low, and peanuts/tree nuts are not common causes, whereas crustaceans are frequent triggers.

Immediate-type food allergy to balsam of Peru

A 48-year old woman presented with a 10-year history of rapid-onset adverse reactions to foods. Reactions involved discomfort in the lips, throat and tongue, throat tightness, an urticarial rash, and a 'sensation of doom'. Suspect triggers included butter toffee popcorn, the aperitif Pernod, cinnamon, toffee apples, ginger nut biscuits, honeycomb confectionary and a supermarket pizza. Additionally, she described contact hypersensitivity to jewellery and cosmetics. Certain soaps and household detergents also provoked urticaria. Skin tests and ImmunoCAP tests to aeroallergens and food allergens were negative; prick-prick testing to the same popcorn was also negative. Nonetheless, we felt her history was convincing, and were suspicious of a linking factor between the identified triggers. We subsequently referred her for patch testing. Patch tests produced a rapid onset urticarial response to myroxylon sulphate (Balsam of Peru); the delayed response was negative. Delayed responses were positive to nickel sulphate and Fragrance mix 1 and 2. We conclude that our patient had an acute-onset hypersensitivity to Balsam of Peru, an aromatic liquid derived from the Myroxolon balsamum tree used in cosmetics, foods, beverages and medicinal products. It contains cinnamic acid, cinnamyl cinnamate, benzyl benzoate, benzoic acid and vanilla, as well as essential oils similar to those found in citrus fruit peel. It most commonly causes a contact dermatitis; highly allergic individuals may suffer adverse reactions after consuming foods containing Balsam of Peru including soreness of the tongue and mouth. Implicated foods include spices, citrus fruit peel, baked goods, aperitifs, benzoic acid and related preservatives. Our patient is unusual in presenting with acute symptoms, mimicking IgE-mediated allergy. Of note, contact urticarial reactions have previously been described to patch testing with Balsam of Peru; the mechanism of such reactions is unclear. Clinicians should be aware of non-classical food ‘allergic’ reactions, especially to pre-prepared foods with complex ingredients.

Japanese Guideline for Food Allergy

Food allergy is defined as "a phenomenon in which adverse reactions (symptoms in skin, mucosal, digestive, respiratory systems, and anaphylactic reactions) are caused in living body through immunological mechanisms after intake of causative food." Various symptoms of food allergy occur in many organs. Food allergy falls into four general clinical types; 1) neonatal and infantile gastrointestinal allergy, 2) infantile atopic dermatitis associated with food allergy, 3) immediate symptoms (urticaria, anaphylaxis, etc.), and 4) food-dependent exercise-induced anaphylaxis and oral allergy syndrome (i.e., specific forms of immediate-type food allergy). Therapy for food allergy includes treatments of and prophylactic measures against hypersensitivity like anaphylaxis. A fundamental prophylactic measure is the elimination diet. However, elimination diets should be conducted only if they are inevitable because they places a burden on patients. For this purpose, it is highly important that causative foods are accurately identified. Many means to determine the causative foods are available, including history taking, skin prick test, antigen specific IgE antibodies in blood, basophil histamine release test, elimination diet test, oral food challenge test, etc. Of these, the oral food challenge test is the most reliable. However, it should be conducted under the supervision of experienced physicians because it may cause adverse reactions such as anaphylaxis.

Allergic Status of Schoolchildren with Food Allergy to Egg, Milk or Wheat in Infancy

Although children allergic to egg, milk or wheat in infancy tend to become tolerant by school age, allergic status after remission has not been well evaluated. We investigated allergic status of schoolchildren who avoided egg, milk or wheat due to immediate-type food allergy diagnosed at less than 1-year-old (early food avoiders), through analysis of a large-scale questionnaire-based survey of schoolchildren.

Diagnosis of food allergy by the radioallergosorbent test

The radioallergosorbent test (RAST) was positive in 52.5% of 200 sera representing 200 food hypersensitivities from 108 patients with a history of definite immediate-type reactions to foods. Corresponding prick test was performed for 170 of the sera. The latter test was positive in 70%, the RAST was positive in 52%, and either prick test or RAST was positive in 74%. It is concluded that the RAST is positive less frequently than the prick test in the diagnosis of immediate-type food allergy in clinically sensitive patients, but that the performance of both tests increases slightly the possibility of confirming the diagnosis. However, the RAST is useful for further evaluating positive prick tests with foods that do not correlate with clinical hypersensitivity.