Specific IgE to Common Food Allergens in Children with Atopic Dermatitis

Background: Atopic dermatitis is a major public health problem, often starting in early childhood and sometimes followed by other allergic diseases. Although hypersensitivity to foods is assumed to play an essential role in the development of atopic dermatitis in some patients, little is known about common food allergens in Iranian children with atopic dermatitis. Objectives: This study was designed to identify probable food allergens in Iranian children with atopic dermatitis and find the relationship between food sensitization and the severity of atopic dermatitis. Methods: This study included 90 children aged 2-48 months with atopic dermatitis. Skin prick tests for cow's milk, hen's egg, almond, potato and soybean were done. Serum specific IgE to 20 food allergens was also screened. Results: Among children with atopic dermatitis, the frequency of food sensitization was 40% by skin prick test and 51% by food-specific IgE. Children with atopic dermatitis were most commonly sensitized to cow's milk (31%), hen's egg (17.7%), tree nuts (17.7%), wheat (12.2%), potato (11.1%), tomato (8.8%) and peanut (8.8%). In 42 children with moderate to severe eczema, sensitivity to food allergens was 78.5% by skin prick test and 88% by serum specific IgE evaluation. Conclusion: Our results showed that cow's milk, hen's egg and tree nuts were the most common food allergens in Iranian children with atopic dermatitis. Sensitization to foods was much higher in patients with moderate to severe atopic dermatitis. Determining specific IgE in children with atopic dermatitis can be helpful in managing these patients.     

Etiologic implication of foods in atopic dermatitis: evidence against

Atopic dermatitis is a typical chronic inflammatory skin disease that usually occurs in individuals with a personal or family history of atopy. Children with atopic dermatitis frequently present IgE-mediated food sensitization, the most commonly involved foods being egg and cow's milk. However, controversy currently surrounds whether food allergy is an etiological factor in atopic dermatitis or whether it is simply an associated factor, accompanying this disease as one more expression of the patient's atopic predisposition. Approximately 40 % of neonates and small children with moderate-to-severe atopic dermatitis present food allergy confirmed by double-blind provocation tests but this allergy does not seem to be the cause of dermatitis since in many cases onset occurs before the food responsible for allergic sensitization is introduced into the newborn's diet.Studies of double-blind provocation tests with food in patients with atopic dermatitis demonstrate mainly immediate reactions compatible with an IgE-mediated allergy. These reactions occur between 5 minutes and 2 hours and present mainly cutaneous symptoms (pruritus, erythema, morbilliform exanthema, wheals) and to a lesser extent, digestive manifestations (nausea, vomiting, abdominal pain, diarrhea), as well as respiratory symptoms (wheezing, nasal congestion, sneezing, coughing). However, these reactions do not indicate the development of dermatitis.Some authors believe that responses to the food in provocation tests may also be delayed, appearing mainly in the following 48 hours, and clinically manifested as exacerbation of dermatitis. However, delayed symptoms are difficult to diagnose and attributing these symptoms to a particular foodstuff may not be possible.Delayed reactions have been attributed to a non-IgE-mediated immunological mechanism and patch tests with food have been proposed for their diagnosis. In our experience and in that of other authors, the results of patch tests with cow's milk do not seem very specific and could be due, at least in part, to the irritant effect of these patches on the reactive skin of children with atopic dermatitis.The involvement of foods in atopic dermatitis will always be difficult to demonstrate given that an exclusion diet is not usually required for its resolution. Food is just one among several possible exacerbating factors and consequently identification of its precise role in the course of the disease is difficult. Further double-blind prospective studies are required to demonstrate the effectiveness of exclusion diets in the treatment of atopic dermatitis.Apart from the controversy surrounding the etiological role of foods, the most important point in atopic dermatitis is to understand that the child is atopic, that is, predisposed to developing sensitivity to environmental allergens; in the first few years of life to foods and subsequently to aeroallergens. Consequently, possible allergic sensitization to foods should be evaluated in children with atopic dermatitis to avoid allergic reactions and to prevent the possible development of allergic respiratory disease later in life.     

Intérêt des tests épicutanés dans la dermatite atopique du nourrisson

The diagnostic workup of allergy is adapted to the age of the child, the clinical features and the suspected allergen. Patch tests investigate delayed hypersensitivity and so theoretically they are indicated in atopic dermatitis of the infant. Nevertheless, not all cases of atopic dermatitis are allergic in origin. Patch tests are recommended in the infant with moderate to severe atopic dermatitis which recurs with topical corticosteroids and in particular circumstances revealed by the history. Elimination procedures in accordance with the results of the allergological investigation always result in improvement in the infant with atopic dermatitis and may modify the natural history of the condition. In the absence of a reference test such as challenge tests in food allergy, the positivity of patch tests is always correlated with their clinical relevance. Patch tests are carried out for contact allergens, inhalant allergens and foods. The food extracts used for these tests should be standardized to allow routine use. Studies are currently being carried out to validate the use of a simplified patch test series in the infant.     

Etiologic implication of foods in atopic dermatitis: evidence in favor

Some of the immunopathologic mechanisms involved in IgE responses are currently being identified; Th2 lymphocytes are known to be activated in patients with atopic dermatitis with subsequent production of the cytokines interleukin (IL)-4 and IL-5, which are responsible for IgE production and eosinophil recruitment. Nevertheless, T cell activation in this disease takes place in two phases. In the first phase, Th2 cells are activated and IL-4, IL-5 and IL-13 are produced; this first stage is produced with the initial activation induced by the antigen. In the second phase there are chronic lesions, Th1 lymphocytes are activated and IFg is produced. This chronic phase is associated with the presence of eosinophils and macrophages that produce IL-12.Numerous articles have demonstrated food sensitization to be an etiopathogenic factor in atopic dermatitis. The prevalence of sensitization varies, depending on the patient's age and the severity of the disease. Children with moderate-to-severe atopic dermatitis have been observed to have a positive skin test and high IgE concentrations to various foods. Nevertheless, a positive skin test to foods in such children does not always implicate these foods as the cause of the clinical manifestations; moreover, in children showing subsequent tolerance to these foods, skin tests can sometimes remain positive and high levels of specific IgE can persist. It is now known that IgE not only participate in the degranulation of mastocyte cells but also in reactions mediated by T cells and other antigen-presenting cells (dendritic cells) which have high-affinity receptors for IgE.The immediate IgE response is well known but it is also known that in addition to the immediate response, a delayed response is also involved, evidenced by the presence of antigen-specific T cells to foods or other allergens such as inhalant allergens. After a strict exclusion diet, children with atopic dermatitis and sensitivity to foods such as milk, egg, flour and soya can develop tolerance; for this reason provocation tests with the food in question should be repeated every 2-3 years. In children with sensitivity to other foods such as dried fruits, fish, and shellfish, sensitivity can sometimes persist into adulthood without tolerance being achieved. In conclusion, there are two groups of children with atopic dermatitis. One group consists of those with atopic dermatitis (allergic disease), which is characterized by early development, high IgE titers, the presence of antigen-specific IgE to allergens and a family history of atopy and which is clinically moderate or severe. Early diagnosis and treatment are important in these children, as is the prevention of progression of the disease to bronchial asthma. The other group consists of children whose dermatitis is clinically atopic in terms of its localization and morphology, who have no demonstrable allergic disease and whose management differs from that in children presenting allergic disease     

Role of aeroallergens in the etiopathogenesis of atopic dermatitis

Atopic dermatitis is a chronic relapsing inflammatory skin disease. It is most frequent in childhood and its clinical manifestations vary with age. The etiopathogenic mechanisms that explain this process are still poorly understood; several studies performed in adults speculate on the possible role of aeroallergens through direct contact with the skin but, because the etiology of this disease varies with age, studies in children of different ages are required.Aims: (i) To determine whether children with atopic dermatitis are sensitized to inhalant allergens. (ii) To determine whether these inhalant allergens cause dermatitis or whether they provoke allergic respiratory disease (asthma, rhinitis) concomitant with atopic dermatitis. (iii) To evaluate whether sensitization to a particular allergen takes place at any age or whether there are differences according to age.Material and methods: This study was performed in the following groups: (i) 64 children with atopic dermatitis, divided into two subgroups, one consisting of 37 children who also presented allergic respiratory disease (asthma, rhinitis) (AR) and another subgroup of 27 patients who presented atopic dermatitis only. (ii) Control group: eight children who presented AR only, to determine whether this group reacted to patch testing with inhalant allergens. (iii) Control group: seven healthy children to rule out non-specific positive tests in the non-atopic population. All groups were divided by age according to the phases of atopic dermatitis: early childhood phase (< 2 years): 21, childhood phase (2-10 years): 37, adolescent phase (> 10 years): 21. In all children total serum IgE determination (RIA), allergen-specific IgE determination (RAST), prick- and patch test were performed. In the three tests the same allergens were used, consisting of the usual components of standardized inhalant and food allergens. When the results of patch testing were positive, biopsy and histopathological analysis were performed and monoclonal antibodies were used to determine reproducibility of the eczematous lesion.Results: Sensitization was found to differ among patients with atopic dermatitis according to whether they presented respiratory symptoms and according to age with a clear predominance of food sensitization in the group aged less than 2 years. In the group aged 2-10 years, mixed sensitization predominated, mainly because of simultaneous respiratory involvement, but it is highly probably that inhalant allergens participate in the etiopathogenesis of atopic dermatitis. In children aged more than 10 years sensitization to inhalant allergens predominated as most presented respiratory symptoms. Patch testing was positive in 34.3 % of patients with atopic dermatitis and approximately half were positive to dust mites. The patch test is of great diagnostic value in atopic dermatitis and none of the tests were positive in the control group. All the biopsies of patch tests with inhalant allergens reproduced the lesions typical of eczema, demonstrating their involvement in the etiopathogenesis of dermatitis.     

La comparaison des taux de sensibilisation IgE-dépendante aux moisissures,aux dermatophytes et aux levures dans les maladies allergiques générales et les dermatoses inflammatoires

We aimed to determine IgE-dependant skin sensitization rates to moulds, dermatophytes and yeasts in patients with typical allergic diseases in comparison to those with inflammatory dermatitis seen over the course of one year. Skin prick tests were done in 267 patients (172 women and 95 men; median age 38 years, range 25–50 years). We allocated them into 8 groups: 64 with head and neck atopic dermatitis; 11 with seborrheic dermatitis; 52 with eczema and not atopic dermatitis other than on the head and neck; 64 with rhinitis, conjunctivitis and asthma; 28 with urticaria; 10 with food allergy; and 12 healthy controls. Skin tests were done with the following aqueous standardized commercial extracts: Alternaria, Penicillium, Aspergillus, Cladosporium, Mucor, Trichophyton, Epidermophyton, Candida albicans, Malassezia and Saccharomyces cerevisiæ. Globally, positive skin test reactions occurred most frequently with the yeast extracts, less to the dermatophytes and even less to the moulds. The results were homogenous among members of each group. The relevance of our tests was reinforced by the fact that the moulds that gave positive skin tests most frequently were those most often isolated in the Belgian environment. In patients with atopic dermatitis of the head and neck, positive tests were most frequent with four moulds and three yeasts; compared to this group, positive tests were less frequent in patients with atopic dermatitis localized to other sites. In inflammatory dermatitis of the head and neck, the study of immediate hypersensitivity to yeasts seems to be important.     

Effect of extensively hydrolyzed milk formula on growth and resistance to bronchitis and atopic dermatitis in infants and toddlers.

OBJECTIVE: This study aimed to evaluate the adverse effects of extensively hydrolyzed milk formula on growth in infants and toddlers. METHODS: Prospectively, 45 infants and toddlers with a positive history of cow's milk allergy confirmed by positive skin prick test and high IgE levels for either alpha-lactalbumin, beta-lactoglobulin, or casein and positive single-blind food challenge received extensively hydrolyzed milk formulas for 1 year. Sex-normalized percentiles of heights and weights of infants and toddlers before their enrollment in the study were compared to those at the end of the study. The contribution of breastfeeding, early use of bottle feeding and intake of adapted or special milk formulas, and history of bronchitis and atopic dermatitis on toddlers' growth were also evaluated by multivariate analysis. RESULTS: Similar percentiles of the children's weight and height were observed at the beginning of the study and 1 year later. According to the multivariate analysis, sex, breastfeeding, early bottle feeding, ingestion of adapted or special milk formulas, atopic dermatitis, and bronchitis were not correlated with either the children's weight or height at diagnosis of the allergy or at 1 year of follow-up (P > .10). Weights and heights were not different between toddlers who had atopic dermatitis or bronchitis during the study period and those who did not. CONCLUSIONS: Growth of infants and toddlers with cow's milk allergy was not affected by the intake of extensively hydrolyzed milk for 1 year. Atopic dermatitis and bronchitis did not appear to have any deleterious effect on these children's growth.     

Urinary eosinophil-derived neurotoxin concentrations in patients with atopic dermatitis: a useful clinical marker for disease activity.

BACKGROUND: It has been reported that measurements of eosinophil-derived neurotoxin (EDN) may be useful for identifying eosinophil activities in allergic diseases including atopic dermatitis. METHODS: EDN concentrations in the urine were measured by enzyme-linked immunosorbent assay, and the number of eosinophils in the peripheral blood was counted in 30 patients with atopic dermatitis. The severity of atopic dermatitis was graded on the criteria proposed by Rajka and Langeland. The disease activity was assessed by each patient on a visual analogue scale (VAS). RESULTS: Urinary concentrations of EDN in patients with atopic dermatitis showed a significant positive correlation with disease severity. Urine EDN concentrations also correlated with VAS scores for itching, skin condition, overall skin symptoms and total VAS score, but not with the VAS score for skin dryness. Urinary EDN concentrations did not correlate with the number of eosinophils in the peripheral blood. CONCLUSIONS: The urinary EDN concentration in patients with atopic dermatitis is a useful clinical marker for monitoring disease activity.     

Risk of allergy to food proteins in topical medicinal agents and cosmetics

The risk of allergy to food proteins in cosmetics and topical medicinal agents is poorly evaluated. IgE dependent contact urticaria and contact dermatitis are observed. Eleven cases (7 infants and 4 women) are reported. Wheat, egg, oats, milk, peanut proteins are incriminated by prick-tests or atopy patch-tests. Cases are related to a previous food allergy and other ones may indicate primary sensitization to topical creams mainly used for skin care of atopic dermatitis. A consecutive exercise induced anaphylaxis to wheat and a long lasting sensitization to wheat have been observed. A clear and accurate identification of food allergens in cosmetics and topical agents is necessary. Given the hyper-permeability of infant skin, topical products containing food proteins of known allergenicity are contra-indicated for neonates, and for infants with atopic dermatitis, which may be associated with skin hyper-permeability.     

Patch tests in the diagnosis of food allergies in the nursing infant

The atopy patch-test has been shown to be useful in diagnosis of delayed reactions in infants with atopic dermatitis or digestive symptoms. The combination of skin prick testing and patch testing can significantly enhance the accuracy in diagnosis of specific food allergy in infants with atopic dermatitis or digestive symptoms.     

Contact sensitization in children with atopic dermatitis

Background

Atopic dermatitis is a common illness in childhood. Children with atopic dermatitis are prone to develop cutaneous sensitization due to skin barrier dysfunction.

Family functioning and illness perception of parents of children with atopic dermatitis, living without skin symptoms, but with psychosomatic symptoms

Emotional factors and a recurrent psychosomatic environment, have been implicated in the evolution of atopic dermatitis. These, in turn, affect the disease. This study was under taken to evaluate the functioning of families with a child that has atopic dermatitis without skin symptoms and the parents' perceptions of their child's disease.Semi-quantitative and cross-sectional study in which questionnaires were applied: one to study family functioning (Espejel et al. scale) and the second to determine aspects of parental perception of their child's atopic dermatitis. Pearson's correlation was used to analyze the correlation between the categories of the Family Function Scale.The most affected categories of family functioning were authority, handling of disruptive conduct, communication, and negative affect. The most significant positive correlations between the categories of family functioning were: authority and support, r=0.867, p<.001; disruptive conduct and communication, r=0.798, p<.001; and support and communication, r=0.731, p<.001. Of the parents, 66.4% thought that the pharmacotherapy used for their child's atopic dermatitis was not effective, and 33.3% of parents stated that the disease had affected their child's daily activities.In families of children with atopic dermatitis, various family environment factors facilitate the recurrence of symptoms even when no cutaneous lesions have been found on the child. The identification and use of family resources to face this disease are aspects that should be taken into consideration during the psychotherapeutic management of these families, putting emphasis on the most affected functional categories of these families in a strategy that should be implanted in a multi-disciplinary context.     

Faut-il contre-indiquer l’utilisation des émollients à base d’avoine chez l’enfant atopique ?

Atopic dermatitis is the first atopic symptom. Local treatment makes use of emollient cream. Oat cream extracts were suspected of causing sensitization. This study was performed in 202 children with atopic dermatitis. Two subgroups were analysed: group 1, 105 children who had applied oat cream (Exomega®, Laboratoires Ducray, France) and group 2, 97 children who had never applied oat cream. Patch tests were positive for Rhealba® oat extract (total extract or protein fractions) in five cases (2.4%): three in group 1 and two in group 2. This result is clinically relevant in group 1, with increased eczema after use of Exomega®. Oat oral food challenge was negative in three children with an oat-positive skin prick test. There was no statistical difference between the two groups concerning age or positivity of oat tests and the results of other allergologic tests. Relevant oat cream allergy in children with atopic dermatitis concerned 1.4% of cases. These data suggest that emollient patch tests should be performed in children with atopic dermatitis, in order to use or exclude emollient cream. Further studies are required to evaluate changes in oat sensitization in older children.     

Does atopic dermatitis cause food allergy? A systematic review

Background

Atopic dermatitis is the commonest chronic inflammatory disorder of the skin, affecting more than 20% of children in industrialised countries and up to 5% of adults. This condition is often associated with other atopic diseases, such as IgE-mediated food allergy (FA). Food allergen recognition via antigen-presenting cells in eczematous skin has been suggested to act as an important mediator of food sensitisation and FA. This would have important implications for prevention and treatment. We aimed to review the association between atopic dermatitis and FA; the effect of FA on atopic dermatitis severity, chronicity, and age of onset; and whether there was a temporal association between atopic dermatitis and FA.

Association of atopy, asthma, allergic rhinoconjunctivitis, atopic dermatitis and intestinal helminth infections in Cuban children

Objective To examine the relationship of past and current intestinal helminth infections with asthma, allergic rhinoconjunctivitis, atopic dermatitis and atopy. Methods Cross‐sectional study of 1320 children aged 4–14 years from two Cuban municipalities. Helminth infections were determined by stool examination and parental questionnaire. Asthma, rhinoconjunctivitis and atopic dermatitis were diagnosed by International Study of Asthma and Allergies in Childhood questionnaire, asthma additionally by spirometry, atopy by skin prick testing. Results Questionnaire‐based frequencies were 21% for asthma, 14% for allergic rhinoconjunctivitis and 8% for atopic dermatitis. According to spirometry, 4% had asthma; 20% had a positive skin prick test. A history of infection for Enterobius vermicularis was associated with increased risk of atopic dermatitis (OR 1.88, P = 0.001) and allergic rhinoconjunctivitis (OR 1.34, P = 0.046), and hookworm with increased risk of allergic rhinoconjunctivitis (OR 2.77, P = 0.021). A positive stool examination for Ascaris lumbricoides infection was negatively associated with atopic dermatitis (OR 0.22, P = 0.007). Asthma and atopy were unrelated to helminth infections. Conclusion Current A. lumbricoides infection protects against atopic dermatitis in Cuban children, while past infection with E. vermicularis and hookworm are risk factors for allergic rhinoconjunctivitis and/or atopic dermatitis. Apparently, interactions differ depending on the type of helminth and atopic disease and on the time of helminth infestation.     

Dermatite atopique de l'enfant et allergie au blé

Wheat allergy amounts to 14–18% during atopic dermatitis, is often manifested by delayed reactions, either on the skin or in the digestive tract. Negative skin prick tests and specific IgE do not rule out the diagnosis. Patch testing seems to be more adapted to this food, but its specificity is low in the young infant. Diagnosis requires an elimination-provocation test, the latter being carried out on several days due to the frequency of delayed reactions.     

Histamine reactivity of affected and unaffected skin in endogenous eczema and in chronic allergic contact dermatitis

In 30 patients with atopic dermatitis and 40 with allergic contact dermatitis in the chronic stage intracutaneous tests were performed with 0.1 ml histamine 1:10,000 in affected and non-affected skin. The erythematous and wheal reactions were compared with 40 age- and sex-matched controls. The diameters of the erythema and wheals were significantly reduced in affected and non-affected skin of the atopic dermatitis (p less than 0.01). In allergic contact dermatitis only the erythema of the affected and non-affected skin was reduced (p less than 0.05), but not the wheal reaction. The erythematous reaction was, however, less reduced in non-affected skin than in the affected one of the allergic contact dermatitis (p less than 0.05). The reduced histamine reactivity seems to be a typical basic mechanism in atopic dermatitis. It is suggested to be due to the histamine mediated immune modulation and the increased release from mast cells, leading to a refractory behaviour of histamine receptors of the blood vessels like in tachyphylaxis. It is interpreted as a secondary phenomenon in allergic contact dermatitis. Although the histamine reaction shows differences for the groups of patients, it is not suitable to discriminate single cases.     

Asthma and allergic diseases in preschool children in Korea: findings from the pilot study of the Korean Surveillance System for Childhood Asthma

Objective: This article was intended to introduce the Korean Surveillance System for Childhood Asthma (KSSCA) and also to determine the factors that increase the risk for the development of asthma and allergic diseases in preschool children in Korea based on the study results.

Methods: The KSSCA pilot study was a web-based, cross-sectional survey that sampled 1002 parents with a biological child aged 2–6?years that visited the website and participated in the survey. This website consisted of a questionnaire designed to measure the history and prevalence of asthma and allergic diseases, the characteristics of dwelling, lifestyle, and the socioeconomic status of the subjects. Using logistic regression analysis, odds ratios (ORs) and 95% confidence intervals (CIs) between each risk factor and disease development were calculated.

Results: The rate of a family where a child had asthma was 7.4%, while 34.7% and 35.9% for allergic rhinitis and atopic dermatitis, respectively. The OR (95% CI) that a child whose parents had an allergic disease and was also diagnosed with an allergic disease was 2.86 (2.20–3.72). Children who lived in the first floor or basement of apartments had a higher risk of atopic dermatitis, as well as children from socioeconomically vulnerable families. Upon analysis of allergic reaction tests and disease development, it was found that asthma was associated with the positive reaction of cockroaches and food, allergic rhinitis with mites, and atopic dermatitis with mold and food.

Conclusion: The study indicated that genetic and some environmental or socioeconomic factors might be important in the development of asthma and allergic diseases among preschool children in Korea through the web-survey.     

A novel atopic dermatitis model induced by topical application with dermatophagoides farinae extract in NC/Nga mice.

BACKGROUND: Atopic dermatitis is a chronically relapsing inflammatory skin disease. Animal models induced by relevant allergens play a very important role in the elucidation of the disease. The patients with atopic dermatitis are highly sensitized with mite allergens such as Dermatophagoides farinae (Df). Therefore, in the present study, we tried to develop a novel model for atopic dermatitis by repeated application with Df extract ointment. METHODS: Df extract ointment was repeatedly applied to the back of NC/Nga mice together with barrier disruption. Atopic dermatitis-like skin lesions were evaluated by dermatitis scores, skin histology and immunological parameters. The effect of corticosteroid and calcineurin inhibitor was also examined. RESULTS: Repeated application of Df extract ointment caused rapid increase in dermatitis scores. Clinical (skin dryness, erythema, edema and erosion) and histological symptoms (dermal and epidermal thickening, hyperkeratosis, parakeratosis and inflammatory cell infiltration) in this model were very similar to those in human atopic dermatitis. Serum total and Df-specific IgE levels were elevated in this model compared with normal mice, and draining lymph node cells isolated from the mice that exhibited dermatitis produced significant amounts of interleukin-5, interleukin-13 and interferon-gamma after re-stimulation with Df. Furthermore, current first-line drugs for the treatment of human atopic dermatitis, corticosteroid and tacrolimus ointments, were effective against the clinical and histological symptoms in this model. CONCLUSIONS: These results suggest that the model we have established is useful for not only elucidating the pathogenesis of atopic dermatitis but also for evaluating therapeutic agents.     

Quoi de neuf en allergologie pédiatrique en 2005 ? Partie 4. Allergie cutanée,alimentaire, médicamenteuse et aux insectes (Une revue de la littérature internationale d'octobre 2004 à octobre 2005)

Allergological work-up and treatment of french children with atopic dermatitis have been the subject of a recent consensus. Food avoidance is useless for prevention of atopic dermatitis, and should be indicated in children with severe atopic dermatitis associated with food allergy only. Exposure, sensitization and allergy rates to nuts increase with age, and avoidance of nuts (even tolerated) is recommended in young children allergic to one or several nuts to prevent the risk of sensitization and allergy to an increasing number of nuts. Threshold values of skin prick-tests and specific IgE determinations with a 90-100% predictive value for food allergy are highly variable from one study to another one, and depend on numerous factors such as age of the children, the allergens used, etc. The diagnostic value of patch-tests and skin application food tests remains controversial. Treatment of food allergy is based on the eviction of the allergenic foods. However, probiotics and « desensitization » to foods may be efficacious in some patients. In children that have outgrown their food allergy, tolerance should be maintened by regular consumption of the foods. However, the parents should be informed that relapses requiring an emergency treatment may occur. Finallly, in children as in adults, repeated mosquito bites induce a desensitization, and most children outgrow their allergy between five to fourteen years.