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Notes: Atopy patch tests (ATPs) are believed to be a useful diagnostic procedure for atopic dermatitis (AD), aiming at the detection of delayed reactions to aeroallergens and food allergens. Our aim was to investigate immune responses to gluten and gliadin in children affected by coeliac disease by performing APTs, and to compare these data to the ones observed in AD patients. 31 children, 15 males and 16 females (mean age ± s.d. = 5,5 ± 3,8 years) affected by coeliac disease underwent APTs with gluten and gliadin. Among these, 15 children were on gluten-free diet at the moment of our examination and 3 patients were affected by AD. 83 AD children not affected by celiac disease, were used as controls. 19,4% and 12,9% of children with coeliac disease proved positive to APTs with gluten and gliadin, respectively. No difference in the frequency and intensity of APT responses were present between the patients on gluten-free diet and the children not on diet. Among AD patients 12% reacted to gluten, whereas no positive reactions to gliadin were observed. Going on these findings, the cellular-mediated reactivity to gliadin in patients with coeliac disease may show a clinical expression by positive APT reactions to gliadin. These represent a specific finding in subjects with coeliac disease when compared to AD children.

Notes: The aim of this study was to evaluate the frequency of contact sensitization to preservatives in a pediatric population and to compare the data to our previous findings referring to the period 1988–1994. From January 1995 to December 2002, 1255 patients aged 7 months-12 years, 583 boys and 672 girls, with suspected allergic contact dermatitis underwent patch testing with our pediatric series of 30 allergens including 5 different preservatives: methyldibromoglutaronitrile, methyl(chloro)isothiazolinone, imidazolidinyl urea, paraben mix, and formaldehyde. Of the 1255 children tested, 108 (8.6%), 52 boys and 56 girls, showed positive reactions to 1 or more of the preservatives listed above. In particular, 55 subjects reacted to methyl(chloro)isothiazolinone, 22 to methyldibromoglutaronitrile, 20 to paraben mix, 17 to formaldehyde, and 13 to imidazolidinyl urea. Among our preservative-positive children, 77% of patients reacted to other haptens of the series, and 44% were affected by atopic dermatitis. In comparison with our previous data referring to the period 1988–1994, a significant increase has been observed in the frequency of positive reactions to methyldibromoglutaronitrile, paraben mix, and formaldehyde. Our findings confirm the importance of patch testing children with preservatives since the wider and wider use of cosmetics in the pediatric age.

Notes: Propolis is an ancient remedy well known for its beneficial properties. The aim of our study was to estimate the frequency of sensitization to propolis in our pediatric patch test population. 1255 children, 583 boys and 672 girls, aged from 7 months to 12 years, were patch tested for suspected allergic contact dermatitis with our pediatric series of 30 allergens including propolis. Out of these, 37% were affected by atopic dermatitis. Among the 1255 children tested, 113 (9%), 60 boys and 53 girls reacted to propolis. In subjects reacting to propolis the dermatitis involved the face in 4% of cases, the trunk in 3%, the hands in 2,2%, and the flexural skin folds of the limbs in 1,7%. The wider and wider use of propolis in “natural products” and biocosmetics, even in the pediatric age, could explain the high frequency of positive patch test responses to propolis we observed.

Notes: Background:  The atopy patch test (APT) was proposed to evaluate IgE-mediated sensitizations in patients with atopic eczema (AE).Objective:  The prevalence and agreement with clinical history and specific IgE (sIgE) of positive APT reactions was investigated in six European countries using a standardized method.Methods:  A total of 314 patients with AE in remission were tested in 12 study centers on clinically uninvolved, non-abraded back skin with 200 index of reactivity (IR)/g of house dust mite Dermatophagoides pteronyssinus, cat dander, grass, and birch pollen allergen extracts with defined major allergen contents in petrolatum. Extracts of egg white, celery and wheat flour with defined protein content were also patch tested. APT values were evaluated at 24, 48, and 72 h according to the European Task Force on Atopic Dermatitis (ETFAD) guidelines. In addition, skin-prick test (SPT) and sIgE and a detailed history on allergen-induced eczema flares were obtained.Results:  Previous eczema flares, after contact with specific allergens, were reported in 1% (celery) to 34% (D. pteronyssinus) of patients. The frequency of clear-cut positive APT reactions ranged from 39% with D. pteronyssinus to 9% with celery. All ETFAD intensities occured after 48 and 72 h. Positive SPT (16–57%) and elevated sIgE (19–59%) results were more frequent. Clear-cut positive APT with all SPT and sIgE testing negative was seen in 7% of the patients, whereas a positive APT without SPT or sIgE for the respective allergen was seen in 17% of the patients. APT, SPT and sIgE results showed significant agreement with history for grass pollen and egg white (two-sided Pr 〉 |Z| ≤ 0.01). In addition, SPT and sIgE showed significant agreement with history for the other aeroallergens. With regard to clinical history, the APT had a higher specificity (64–91% depending on the allergen) than SPT (50–85%) or sIgE (52–85%). Positive APT were associated with longer duration of eczema flares and showed regional differences. In 10 non-atopic controls, no positive APT reaction was seen.Conclusion:  Aeroallergens and food allergens are able to elicit eczematous skin reactions after epicutaneous application. As no gold standard for aeroallergen provocation in AE exists, the relevance of aeroallergens for AE flares may be evaluated by APT in addition to SPT and sIgE. The data may contribute to the international standardization of the APT.