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Notes: Atopic dermatitis (AD) is considered a T-cell mediated disease. Activated T-cells, mainly of the CD4-subtype. are abundantly present in lesional AD skin. Although not many intact eosinophils are present, deposits of eosinophil derived major-basic-protein (MBP) and eosinophil-cationic-protein (ECP) suggest eosinophil involvement. After patch testing AD patients with aeroallergens, an eczematous reaction develops after 24 48 hr at the site of application. This patch test reaction shows macroscopic resemblance to lesional AD skin and does not take place in normal individuals, asthma and allergic rhinitis patients. Lymphocytes together with eosinophils infiltrate into the dennis 26 hr after allergen application. Twenty-four to forty-eight hours after patch testing, eosinophils are in an activated state since they release ECP (being EG2-positive). At this point in time eosinophils have also infiltrated the epidermis. Here they are EG2-negative. Forty-eight to seventy-two hours after patch testing the eczematous reaction decreases. This coincides with disappearance of eosinophils from both the dermis and the epidermis; then, a dendritic staining pattern can be observed in the epidermis with anti-eosinophil peroxidase. Thus, eosinophils infiltrate the dermis and epidermis after patch testing AD patients with aeroallergens and release part of their granular constituents. Recent in vitro investigations revealed that eosinophils from the circulation of AD patients react more powerfully in in vitro test systems such as chemi luminescence, chemotaxis and endolhelial adherence and transmigration. 11 is very likely that this activated (= primed) state is caused by the influence of lymphocyte-derived cytokines like IL-3, IL-5 and GM-CSF, since activated lymphocytes in the circulation (and tissue) may release these cytokines. The primed state of the eosinophils may facilitate tissue inlillration. The subsequent activation of eosinophils within the tissue leading to mediator release and the function of these mediators need to be further elucidated. The close similarity between the cellular events after a patch test reaction to aeroallergens in AD patients and those present in lesional AD skin suggests that the patch test reaction may be a helpful in rim model to study the pathogenesis of AD. The prominent involvement of lymphocytes and eosinophils in this reaction also suggests some similarity with late phase reactions (LPR) observed in the skin after intracutaneous allergen challenge.

Notes: Background Allergic rhinitis, asthma and atopic dermatitis are closely associated. Although population-based studies report a high prevalence of rhinitis among asthma patients, less is known of the association between rhinitis and atopic dermatitis and the severity of concomitant rhinitis.Objectives We aimed to determine the prevalence and severity of allergic rhinitis among asthmatics and patients with atopic dermatitis and assessed whether age and comorbidity influence the severity of rhinitis signs and symptoms.Methods Three hundred and twenty-five patients recruited for a multicentre trial to study the effect of encasings of mattresses, pillows and duvets on signs and symptoms of allergic rhinitis and/or asthma and/or atopic dermatitis recorded visual analogue scores (VAS) and daily symptom scores and underwent nasal challenge tests with house dust mite (HDM).Results Based on history and clinical symptoms 92% of the 164 asthmatic patients and 85% of the 86 patients with atopic dermatitis could be diagnosed as having rhinitis. Inclusion of a positive provocation to HDM did not result in a substantial lower prevalence of rhinitis. Subjects reported moderate symptoms, with mean rhinitis VAS scores ranging from 40.0 to 55.0. Presence of atopic dermatitis was associated with lower rhinitis VAS and symptoms scores, whereas in multivariate analysis the presence of asthma was positively associated with nasal responsiveness to HDM.Conclusion The prevalence of nasal symptoms in patients with bronchial asthma or atopic dermatitis and sensitized to house dust mites is high. Although the majority of patients experience mild to moderate symptoms, the presence of nasal disease needs to be examined in all patients with atopic disorders.

Notes: Background:  Eosinophils may play an important role in the pathogenesis of atopic dermatitis (AD). Interleukin-5 is essential for eosinophil growth, differentiation and migration. A monoclonal antibody to human interleukin-5 (mepolizumab) was developed for atopic diseases. This study was designed to study the effect of mepolizumab in AD.Methods:  Two single doses of 750 mg mepolizumab, given 1 week apart, were studied in patients with moderate to severe AD using a randomized, placebo-controlled parallel group design. The primary endpoint of ‘success’ to treatment was defined as the percentage of patients with at least ‘marked improvement’ after 2 weeks as assessed by the Physician's Global Assessment of Improvement (PGA). Furthermore, SCORing AD (SCORAD), pruritus scoring, number of blood eosinophils and serum thymus and activation-regulated chemokine (TARC) values served as secondary endpoints. Fluticason propionate cream 0.05%, once daily could be used as rescue medication from day 16 if no improvement was recorded.Results:  Eighteen patients received mepolizumab and 22 placebo treatment. Peripheral blood eosinophil numbers were significantly reduced in the treatment group compared with placebo (P 〈 0.05). No clinical success was reached by PGA assessment (P = 0.115), SCORAD (P = 0.293), pruritus scoring and TARC values in the mepolizumab-treated group compared with placebo. However, modest improvement (〈50% improvement) assessed by PGA was scored significantly more in the mepolizumab-treated group compared with placebo (P 〈 0.05).Conclusion:  Two single doses of 750 mg mepolizumab did not result in clinical success in patients with AD, despite a significant decrease in peripheral blood eosinophils.

Notes: Background:  Environmental control has been put forward as an integral part of the management of house dust mite (HDM) allergy in sensitized patients. To validate this statement allergic disorders involved in HDM allergy – allergic asthma, rhinitis and atopic eczema/dermatitis syndrome (AEDS) – should be taken together and studied in terms of the efficacy of environmental control. Because a generic quality of life questionnaire exceeds the border of disease, this may be used as major outcome parameter.Research objective:  To study the effects of bedding encasings in HDM allergic patients with asthma, rhinitis and AEDS.Material and methods:  A total of 224 adult HDM allergic patients with rhinitis and/or asthma and/or dermatitis were randomly allocated impermeable or nonimpermeable encasings for mattress, pillow and duvet. Short form 36 (SF-36) was filled in at baseline and after 12 months.Results:  Lower physical (P = 0.01) and emotional (P 〈 0.001) sumscores were seen in females. Also, the presence of asthma resulted in lower physical sumscore (P = 0.01). However, no effect was seen of encasings on either sumscore.Conclusion:  Bedding encasings do not improve quality of life in a mixed population of subjects with combinations with rhinitis, asthma and atopic dermatitis and sensitized to HDMs.

Notes: Background:  The atopy patch test (APT) is an in vivo model to study the induction of eczema by inhalant allergens. This study was designed to compare two commonly used APT methods.Methods:  In the first method, the allergen is dissolved in aqueous solution, which is applied on tape-stripped skin. In the second method, the allergen is dissolved in petrolatum and applied without tape stripping. Thirteen patients with atopic dermatitis sensitized to inhalant allergens were patch tested using both methods. Reactions were evaluated macroscopically and microscopically after 48 h.Results:  Nine out of 13 patients displayed a positive reaction for both methods. One patient had a positive APT for the aqueous method alone and three for the petrolatum method alone. Reactions were significantly stronger when using the petrolatum method. Histological evaluation of the nine patients positive for both methods showed no significant differences in number of eosinophils, T-cells and neutrophils.Conclusion:  The APT using the petrolatum vehicle induces a higher number of positive reactions and is significantly stronger relative to the APT using allergen in aqueous vehicle. The cellular influx in both test methods is comparable. Both methods can be used to study the mechanisms in the induction of eczema by inhalant allergens.

Notes: Background: The serology of peanut allergy seems to be different in various parts of the world. We analyzed the composition of 13 samples of three varieties of peanut in order to compare their allergenic nature. Methods: Peanut cultivars that are commonly processed in the West were analyzed for protein content, protein composition, and Ara h 1 and Ara h 2 content by biochemical methods. IgE-binding properties were analyzed by ELISA using serum from patients with documented peanut allergy. Results: Total protein contents were comparable for all tested samples (24–29%), and proteins were extractable to the same extent. SDS–PAGE patterns differed slightly, but all major bands were visible in all samples (molecular masses of approximately 14–100 kDa under reducing conditions). Ara h 1 and Ara h 2 were quantified by SDS–PAGE densitometry and were expressed as percentage of the total protein content. Ara h 1 was in the range 12–16%, whereas Ara h 2 was 5.9–9.3%. In view of the analytic uncertainty of this determination, the content of both Ara h 1 and Ara h 2 was not significantly different between the tested samples. In an IgE-binding inhibition ELISA, the affinities of the peanut proteins for peanut-specific IgE were measured. Minor differences were observed between the tested samples, with the most potent IgE-binding sample having a two times higher ability to bind IgE than the weakest IgE-binding sample. Conclusions: The results suggest that peanuts of different varieties, and from different parts of the world contain similar proteins, including Ara h 1 and Ara h 2. Consequently, the IgE-binding properties are similar to a great extent. This indicates that differences in the serology of peanut allergy may not originate from differences in the allergen composition of the peanut.

Notes: Background:  Jackfruit allergy has been reported just once. It is unknown whether this food allergy is caused by direct sensitization or cross-sensitization to pollen allergens.Objective:  Establish whether jackfruit allergy is linked to birchpollen allergy.Methods:  Two jackfruit allergic patients and five patients with birchpollen-related apple allergy were recruited. Sensitization to pollen and plant foods was assessed by skin prick test (SPT), radio-allergosorbent test (RAST) and immunoblot. RAST analysis was performed for Bet v 1 and Mal d 1. Cross-reactivity was evaluated by RAST and immunoblot-inhibition. Biological activity of immunoglobulin E (IgE) was measured by basophil histamine release. Allergy to jackfruit was evaluated by double-blind placebo-controlled food challenge (DBPCFC) or open challenge (OC).Results:  In both patients DBPCFC confirmed the reported jackfruit allergy. SPT was 41 and 27 mm2 and specific IgE to jackfruit was 5.9 and 0.8 IU/ml, respectively. Immunoblot analysis revealed IgE reactivity at Mr of approximately 17 kDa. The Bet v 1-related nature of this allergen in jackfruit was demonstrated by RAST and immunoblot inhibition. To assess whether jackfruit allergy might be common in patients with combined birchpollen-fruit allergy, five such patients underwent an OC with jackfruit. All five had OA-like symptoms.Conclusions:  Jackfruit allergy can be added to the list of birchpollen-related food allergies. Increased consumption of this fruit will result in a rise in allergic reactions.