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Notes: Abstract For quantitative use of skin prick tests (SPTs), the circumference of the wheal and/or the flare is outlined by a pen, and transferred to a paper by adhesive tape. The biological response is considered proportional to this area. We have previously developed software, the SPT-scanner, for determination of SPT areas (5–500 mm2) by a hand-held scanner and a personal computer. This study is aimed at comparing the SPT-scanner with another semiautomated system, where the outline of the wheal is followed by a digitizer pen. Comparing 2080 SPT areas from a pharmacological study of cetirizine, the two systems correlated well (r=0.980,p〈0.001), the digitizer generally giving larger areas than the SPT-scanner. Probably, the line is considered as a part of the wheal/flare in the digitizing system, whereas the scanner only detects areas within the circumference. In conclusion, the SPT scanner is objective and reproducible for rapid SPT area determination.

Notes: The pattern of patch test reactivity to nickel sulfate and fragrance mix was studied with respect to patch test performance, reproducibility and clinical relevance in a population of unselected infants followed prospectively from birth to 18 months of age. TRUE Test™ patches with nickel sulfate in 3 concentrations, 200, 66 and 22 µg/cm2, and fragrance mix 430 µg/cm2 were used. A likely case of nickel sensitivity was defined as a reproducible positive reaction with at least homogeneous erythema and palpable infiltration occurring at least 2× and present at both the 12 and 18 months follow-up. 543 infants (268 girls and 275 boys) were tested at least 1×, 304 were tested at both 12 and 18 months. The prevalence of a reproducible positive reaction to nickel was 8.6% (20 girls and 6 boys). A transient positive reaction was observed in 111 children. Clinical relevance of nickel sensitivity was found in only 1 child. No reproducible positive reaction to fragrance mix was found. The high proportion of transient patch test reactivity to nickel sulfate 200 µg/cm2 indicates that this standard concentration used for adults cannot be applied to infants. The interpretation of a single positive nickel patch test in infants must be assessed with caution and it is probably of non-specific or irritant nature.

Notes: Objectives:  Study patch test reactivity to nickel sulphate and fragrance mix in a population of unselected infants with focus on reproducibility, clinical relevance, and nickel patch test concentration.Method:  The data presented is part of a clinical epidemiological study of allergic diseases in newborns followed prospectively with questionnaire, clinical examination and testing at 0, 3, 6, 12 and 18 months of age. TRUE Test patches were used with nickel sulphate in 3 concentrations: 200, 66, 22 ìg/cm2 and fragrance mix 430 ìg/cm2. A positive reaction suggesting sensitisation was defined as at least palpable erythema present at both the 12 and 18 months follow-up visits.Results:  A total of 543 children (268 girls, 275 boys) were patch tested at least once, 304 children were tested at both 12 and 18 months. The prevalence of a reproducible positive reaction to nickel sulphate 200 ìg/cm2 was 8.6%(20 girls, 6 boys). A transient reactivity was observed in 111 children (53 girls, 58 boys). A clinical relevance to nickel was found in only one child. There was no association between number of patch test procedures performed and reactions to nickel sulphate. Reproducible reactivity to fragrance mix was not found.Conclusion:  A high proportion of transient patch test reactivity to nickel sulphate 200 ìg/cm2 was found. Patch testing with nickel in concentrations used for adults cannot be recommended in infants. The interpretation of a singular positive nickel patch test in small children must be assessed with caution. Allergic reactions to fragrance mix were not found in this age group.

Notes: Background At present, several in vitro tests for immunoglobulin E (lgE)-mediated food allergy are available. An estimation of the diagnostic accuracy of the various tests used in predicting clinical sensitivity to codfish in a well-characterized allergic material is necessary.Objectives To compare the diagnostic value of four specific IgE tests, and histamine release from basophils (HR) in identifying clinical type I allergy to codfish. As a true diagnosis, double-blind, placebo-controlled food challenges (DBPCFC) were employed.Methods Eight clinically codfish-allergic adult patients were investigated together with 30 codfish-tolerant control subjects for evidence of codfish-specific reactivity by Phadebas RAST® (PHA). Pharmacia CAP System RAST® (CAP), Magic® Lite (ML) and HR. To characterize the diagnostic properties of a freshly prepared raw codfish extract, experiments were conducted employing an in-house radioallergosorbent test (RAST). the Maxisorp RAST (MAXI) and HR. Finally, protein profile and IgE-reacting allergens were detected by means of sodium dodecyl sulfate-polyacrylamide gel elcctrophoresis (SDS-PAGE) and immunoblotting.Results The sensitivities of HR with commercial extract and the three commercially available specific IgE analyses were 0.83 and 1.00 respectively. Specificities were 1.00 (H R) and 0.87-1.00 (specific IgE tests). Ereshly prepared codfish extracts improved the sensitivity of HR. SDS-PAGE revealed ∼29 bands (〈 14.3-200 kDa) including a band of 12-13 kDa. and in immunoblotting 18 sera identified 17 IgE-binding bands. The protein migrating at 12-13 kDa was identified in the fresh codfish extract tested with gen from all clinical codfish allergies, while no significant reaction was seen in the control subjects.Conclusion Based on the small number of adult patients included in our study, the in vitro assays with commercial and fresh extracts have high sensitivity and are acceptable for screening for codfish allergy. Specificity of Phadebas. CAP. and our in-house RAST was less than unity, whereas ML and strong binding of IgE to a 12-13kDa protein completely matches DBPCFC results, and thus seems sufficient for establishing the diagnosis.

Notes: When skin-prick tests (SPTs) are used quantitatively, the circumference of the weal and/ or the flare is outlined using a felt tip pen, and transferred to paper by adhesive tape. The aim of the study was to develop and validate a procedure, objectively and precisely determining these areas after transfer to paper. A system was developed enabling the drawing of the area of weal or flare to be read by a hand-held scanner and calculated on a personal computer. Areas in the 5-500 mm2 range could be determined with day-to-day and interoperator coefficients of variation (CVs) of 3.3% and 1.1%, respectively. Accuracy was determined in two ways: by correlation to cutting/weighing of four times enlarged SPT areas (r2= 0.0, P〈 0.0) and by measuring standardized areas (deviations less than intra-assay CV, i.e. 1-2%). For comparison, CVs of alternative methods were also determined: eight different areas (9-76 mm2) were evaluated in quadruplicate using the SPT-scanner (CV=1.1%), by cutting/weighing of paper (CV = 2.2%), by digitizing (CV = 4.4%) or by measuring longest and orthogonal diameters (CV= 13.13%). In conclusion, the scanning device and software provides an objective and reproducible procedure for rapid determination of SPT areas. When areas are determined by scanning, digitizing or cutting/weighing the variations in area determination becomes negligible compared to the variations of the entire skin test procedure.

Notes: The ability of skin prick test (SPT) and histamine release from basophils (HR) to diagnose clinical type I allergy to egg and milk was investigated as compared with double-blind, placebo-controlled food challenge (DBPCFC) in 17 adults suspected of type I egg and/or milk allergy. In both SPT and HR, commercial allergen extracts commonly used for SPT were compared with fresh, standardized foods. With commercial extracts the overall sensitivities of SPT and HR were 0.75 and 0.56 respectively, and none of the tests showed concordance with DBPCFC. With fresh, standardized foods the overall sensitivities of SPT and HR were 1.00 and 0.89 respectively, and both tests now showed a significant concordance with DBPCFC (P〈0.05). Specificity was only slightly improved in SPT, and unchanged in HR. Thus, the use of fresh, standardized foods significantly improved the outcome of both tests, as regards to sensitivity and concordance with DBPCFC. The diagnostic ability of SPT and HR appear to be strongly influenced by the allergen quality.

Notes: Background While the ingestion of small amounts of an offending food can elicit adverse reactions in individuals with IgE-mediated food allergies, little information is known regarding these threshold doses for specific allergenic foods. While low-dose challenge trials have been conducted on an appreciable number of allergic individuals, a variety of different clinical protocols were used making the estimation of the threshold dose very difficult.Objective A roundtable conference was convened to develop a consensus clinical protocol for low-dose challenge trials for the estimation of threshold doses for specific allergenic foods.Methods In May 2002, 20 clinical allergists and other interested parties were invited to participate in a roundtable conference to develop consensus of the key elements of a clinical protocol for low-dose challenge trials.Results A consensus protocol was developed. Patients with convincing histories of food allergies and supporting diagnostic evidence including past challenge trials or high CAP–RAST scores can be enrolled in low-dose challenge trials. Care must be taken with younger patients to assure that they have not outgrown their food allergy. An approach was developed for the medication status of patients entering such trials. Challenge materials must be standardized, for example, partially defatted peanut flour composed of equal amounts of the three major varieties of peanuts (Florunner, Virginia, Spanish). Challenge materials must be appropriately blinded with sensory evaluation used to confirm the adequacy of blinding. A double-blind, placebo-controlled design should be used for low-dose challenge trials. Low-dose challenge trials would begin at doses of 10 μg of the allergenic food and would continue with doses of 100 μg and 1 mg followed by specific higher doses up to 100 mg depending upon the expert judgement of the physician; even higher doses might be applied to assure that the patient is indeed reactive to the particular food. A 30-min time interval would be used between doses, and reactive doses would be expressed as both discrete and cumulative doses. The goal of each challenge would be to develop objective symptoms; trials should not be discontinued on the basis of subjective symptoms only. Statistically, a minimum of 29 patients would be enrolled in low-dose challenge trials for each allergenic food because 0 reactors out of 29 patients at a particular dose allow the conclusion that there is 95% certainty that 90% of allergic individuals will not react to that dose.Conclusion A consensus protocol was developed. Using this protocol, it will be possible to estimate threshold doses for allergenic foods, the lowest amount that elicits mild, objective symptoms in highly sensitive individuals.

Notes: Background  Atopic diseases are common in children and adolescents. However, epidemiological knowledge is sparse for hand eczema and allergic contact dermatitis in this age group. Furthermore, no population-based studies have evaluated the prevalence of atopic diseases and hand and contact dermatitis in the same group of adolescents. Objectives  To assess prevalence measures of atopic dermatitis (AD), asthma, allergic rhinitis and hand and contact dermatitis in adolescents in Odense municipality, Denmark. Methods  The study was carried out as a cross-sectional study among 1501 eighth grade school children (age 12–16 years) and included questionnaire, interview, clinical examination and patch testing. Results  The lifetime prevalence of AD was 21·3% (girls 25·7% vs. boys 17·0%, P 〈 0·001) using predefined questionnaire criteria. The 1-year period prevalence of AD was 6·7% and the point prevalence 3·6% (Hanifin and Rajka criteria). In the interview the lifetime prevalence of inhalant allergy was estimated as 17·7% (6·9% allergic asthma, 15·7% allergic rhinitis). The lifetime prevalence of hand eczema based on the questionnaire was 9·2%, the 1-year period prevalence was 7·3% and the point prevalence 3·2%, with a significant predominance in girls. A significant association was found both between AD and inhalant allergy, and between AD and hand eczema using lifetime prevalence measures. The point prevalence of contact allergy was 15·2% (girls 19·4% vs. boys 10·3%, P 〈 0·001), and present or past allergic contact dermatitis was found in 7·2% (girls 11·3% vs. boys 2·5%). Contact allergy was most common to nickel (8·6%) and fragrance mix (1·8%). Conclusions  High prevalence figures were found for atopic diseases, hand eczema and allergic contact dermatitis, and the diseases were closely associated. A considerable number of adolescents still suffers from AD, and a considerable sex difference was noted for hand eczema and allergic contact dermatitis. Nickel allergy and perfume allergy were the major contact allergies. In the future this cohort of eighth grade school children will be followed up with regard to the course and development of atopic diseases, hand eczema and contact dermatitis.

Notes: Background:  The definition of allergic rhinitis and the classification of its severity and treatment have advanced in recent years following the publication of the Allergic Rhinitis and its Impact of Asthma (ARIA) document. The ARIA and the European Academy of Allergology and Clinical Immunology (ARIA/EAACI) have published a set of recommendations that outline the pharmacological and clinical criteria to be met by medications commonly used in the treatment of allergic rhinitis.Methods:  An international group of experts met to assess the profile of the antihistamine, desloratadine, under the ARIA/EAACI criteria. Data on desloratadine were collected from peer-reviewed clinical studies and review articles, which were corroborated and augmented by comprehensive public access documents from the European Medicines Evaluation Agency (EMEA).Results and conclusion:  Based on this systematic review, it was concluded that the efficacy, safety and pharmacology of desloratadine broadly meet the ARIA/EAACI criteria for antihistamines.