Corticosteroid contact allergy: an EECDRG multicentre study

This article describes the results of an EECDRG multicentre study on contact allergy to corticosteroids. A total of 7238 patients were investigated: 6238 in 13 centres in the course of 1993, and 1000 patients in 1 centre in 1993 and 1994. The 5 corticosteroids tested were budesonide 0.1% pet., betamethasone-17-valerate 1% pet., clobetasol-17-propionate 1% pet., hydrocortisone-17-butyrate 1% eth., and tixoeortol-21-pivalate 1%., pet.; 189 (2.6%) gave a positive patehtest reaction (+, ++, +++)to at least 1 of the corticosieroids. The data regarding the corticosteroid-sensitive patients, as well as the patchtest results, were recorded on a standardized form.     

The oak processionary caterpillar (Thaumetopoea processiona L.) and man: urticating apparatus and mechanism of action

The urticating apparatus of the oak processionary caterpillar was studied by electron microscopy at times when this species was exceptionally abundant in France. Proteins of urticating hairs were studied by electrophoresis on acrylamide gel and were compared with thaumetopoein, an urticating protein of the pine processionary caterpillar, using immunological techniques. A thaumetopoein-like protein was found to be present in oak processionary urticating hairs. This protein has a histamine-releasing effect in the guinea-pig. Contact dermatitis caused by the oak processionary caterpillar is described and compared to that produced by the pine processionary caterpillar.     

Enantiospecificity in allergic contact dermatitis A review and new results in Frullania-sensitive patients

Allergic contact dermatitis is essentially enantiospecific: sensitization to one enantiomer generally does not imply elicitation to the mirror-image allergens. Examples from patients allergic to Frullania, and from the literature (usnic acids, 4-methoxydalbergiones, gamma-methyl-alpha-methylene-gamma-butyrolactones, frullanolides) are discussed.     

Routine patch testing with frullanolide mix: an European Environmental and Contact Dermatitis Research Group multicentre study

Contact sensitivity to plants containing 1 or more sesquiterpene lactones (SLs) is difficult to diagnose. The mixture of SLs (SL mix) has been shown to detect only about 60% of sensitized individuals. In order to improve the diagnosis of sensitization to plants containing SLs, we have tested a mixture of frullanolides contained in Frullania dilatata and Frullania tamarisci at 3 different concentrations (0.01%, 0.033% and 0.1% in petrolatum). 8605 consecutive eczema patients in 1 North American and 15 European dermatology departments were tested with this mix, and 0.35% of positive cases to the different concentrations were found. Routine use of this mix permitted detection of only a small percentage of extra cases and did not improve the SL mix score. The frullanolide mix should therefore be restricted to investigations in particular geographical zones and/or in particular occupations.     

Patch test reactions to mite antigens: a GERDA* multicentre study

We performed patch tests with Dermatophagoides pteronyssinus (Dp) antigen from 2 different sources in 355 non-randomly selected patients with atopic dermatitis(AD) and 398 subjects of a control group. The study demonstrated that contact sensitization to mites occurred in an appreciable% of AD cases(20.8%). Using commonly available assay products. The differences recorded between the 2 materials tested were related to the concentration of P1 antigen. Non-atopic patients rarely showed positive reactions to Dp (0.75%), when strict criteria for readings were applied and if 2 readings were performed, Patients with positive patch tests did not necessarily show positive immediate skin tests. It would be useful to carry out tests systematically in atopic patients, even if it is not yet known what modern treatment would be best for the patient. Laboratories still do not provide standardized house dust mite preparations measuring and codifying their biological acitivity for use in patch of better test materials, in syringes with homogeneous dispersion and concentration.     

Allergic contact dermatitis to various salols (phenyl salicylates)

Summary Patients sensitive to phenyl salicylate (salol) were patch-tested to several aryl salicylates. The most powerful derivative was p-nitrophenyl salicylate (compound 5). This can be explained by an unusually good interaction with protein (nucleophilic substitution on the carboxyl carbon). All these results were confirmed by experimental sensitization of guinea pigs to salol and cross-reaction to substituted salols. The results are in line with current theory of allergic contact dermatitis, i.e., an in vivo formation of a hapten-protein conjugate.     

European multicenter study of TRUE Test™, Panel 2

Panel 2 of the standardized, ready-to-apply patch test, the TRUE Test, has been evaluated on 808 patients with suspected contact dermatitis. The patients were tested with 11 different allergens and the negative control, and compared with corresponding allergens in pet. (or aq.) in Finn Chambers fixed with Scanpor. The TRUE Test, Panel 2 and the control were applied symmetrically on the upper back. Left/right application of the respective test varied at random. Most tests were removed after 48 h and evaluated after 72 or 96 h, according to generally accepted recommendations. There were positive test reactions to all 11 allergens tested in the patient group. The concordance of positive reactions (1+, 2+, 3+) was 63% between TRUE Test, Panel 2 and the control method; 17% of positive reactions occurred only with TRUE Test, Panel 2 and 20% only with the compared method. Approximately 75% of all positive test reactions were explained by the patients' present or past history. Irritant/questionable reactions occurred in the same frequency for the 2 methods. Such reactions were recorded in less than 1% of all patches applied. No late reactions were recorded.