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Notes: To determine normal levels of transepidermal water loss (TEWL), capacitance and sebum according to different sex and age groups, 93 healthy subjects were studied at 14 different anatomical locations with three different instruments: the Evaporimeter EP 1, the Corneometer CM 820, and the Sebumeter SM 810, evaluating respectively the transepidermal water loss, the capacitance and the causal level of sebum. Differences depending on the anatomical site were noticed. Unlike the capacitance, the transepidermal water loss and the causal level of sebum significantly decreased according to age. Furthermore, in some sites, male subjects showed a significantly higher transepidermal water loss than females, while hydration of the horny layer expressed by the capacitance showed an opposite trend. Correlations between the above-mentioned skin parameters were calculated: a positive correlation between TEWL and hydration was observed only at plantar and palmar areas.

Notes: Using 3 different ready-to-apply patch test systems (Epiquick®= EPI; Rapid Patch Test®= RPT; TRUE TestTM= TT), 316 patients sensitive to at least one allergen were studied in order to investigate the reproducibility of these tests in comparison with the Finn Chamber ®(FC) technique. Each patient was tested with a different ready-to-use system. Each test was compared to the same allergen applied with FC to either side of the upper back. Comparisons were made using EPI, RPT, and TT in 93 (183 tests), 119 (262 tests), and 104 (242 tests) patients respectively. When a positive test result occurred on only one side of the back, the concordance was defined as negative. Similarly, doubtful reactions on either side corresponding to positive or negative results were considered as non concordant. The concordance of positive reactions was 80.9% between the EPI and the FC technique, 77.5% between the RPT and the FC technique, and 72.3% between the TT and the FC technique. The frequency of questionable (+?) and irritant reactions (IR) was about the same for the different tests. Nevertheless, when comparing the positive reactions vs +?, IR, or negative reactions in paired tests, positive results were more frequently obtained with the FC technique. Our data suggest that the standard method with FC allows a better detection of contact allergy than the new ready-to-use systems tested in this study.

Notes: We have described 100 subjects sensitized to textile dyes. Of these, 16 had clinically been suspected of having a textile dermatitis from among 1145 patients referred for patch testing. 41 patients were identified from among 861 consecutive subjects tested with the GIRDCA (Italian Research Group on Contact and Environmental Dermatitis) standard series supplemented with 4 disperse dyes (Disperse Blue 124, Disperse Red I, Disperse Yellow 3. Disperse Orange 3), The remaining 43 patients were identified from among 746 subjects tested with the GCRDCA standard series, supplemented with the 4 disperse dyes mentioned above and a further series of 12 other textile dyes, The clinical picture was extremely variable: most patients had a typical eczematous dermatitis, but we also observed persistent erythematous-wheal-type reaction. a transient urticarial dermatitis and an erythema-multiforme-like eruption Among these textile dyes, Disperse Blue 124 caused most reactions. With the addition of the 4 disperse dyes to the GIRDCA standard series, we identified 4.8% sensitized 10 textile dyes. a much higher figure than the 1.4% observed among patients being patch tested on the basis of their history and the clinical findings; the addition of a further 12 textile dyes to the series further increased the detection rate to 5.8%. We stress the importance of routinely patch testing with textile dyes, which can help to elucidate the cause of certain kinds of atypical dermatitis

Notes: Background/aims: The possibility of identifying allergic reactions while they are not clinically evident could prove extremely useful in studying the evolution of skin responses in experimentally-induced contact dermatitis. In drug research and in cosmetological research, the sensitizing properties of new molecules or haptens present in the product in a low concentration also need be clarified. The object of the present study was to validate noninvasive techniques and their use for the study of subclinical allergic reactions. Methods: 70 nickel-sensitized subjects previously standard tested with 5% nickel sulphate in petrolatum were challenged with a 0.05% nickel sulfate solution on the volar aspect of the forearm, application for 24 h and measurement at 72 h. Colorimetry, evaporimetry (transepidermal water loss, TEWL) and high-frequency echography were used to characterize reactions. Results: Colorimetry and TEWL did not show any significant differences between patch test areas and control areas. Skin thickness determination, conversely, evidenced a significant increase both with respect to baseline values and control areas. Conclusion: Echographic evaluation is able to detect modification of skin thickness of subclinical allergic patch test reactions to nickel sulfate while colorimetry and TEWL failed to detected such minute changes.

Notes: Abstract The human skin blanching assay is a well established method for ranking the efficacy of corticosteroids after epicutaneous application. Vasoconstriction is a pharmacological activity, which correlates well with the clinical efficacy, the intensity of skin blanching after a single application under occlusion corresponding, generally, to the clinical efficacy after repealed application without occlusion. However, in studies dealing with the comparison between the vasoconstriction assay and the evaluation of the clinical effects on inflammatory skin diseases, some exceptions to this correlation have been reported. Therefore, in a pre-clinical phase, it would be useful to combine the blanching assay with at least one anti-inflammatory assay. In the present study the blanching assay and the allergic contact dermatitis inhibition test were performed in parallel, in order to compare the two testing procedures in the same group of subjects, utilizing standardized study designs supported by objective means of evaluation. Three commercial preparations of corticosteroids containing clobetasol propionate (CP), clobetasone butyrate (CB) and hydrocortisone acetate (HA), respectively, were employed both to treat nickel-induced positive patch test responses on the volar forearms, and to perform a vasoconstrictor assay on normal forearm skin in 16 nickel-sensitised healthy volunteers. For evaluating skin blanching, we employed colorimetric measurements, whereas for the quantitative determination of the inhibition of the intensity of allergic patch test reactions, 20 MHz B-scanning supported by image analysis was used. Both colorimetric and echogenicity values enabled us to distinguish between the three corticosteroids (at the 17 h evaluation and the 64 h assessment, respectively). A fair correlation was noted between colorimetric and echogenicity values. Both testing procedures ranked the three corticosteroids in the expected order. Corticosteroid preparations should be compared using methods which allow different effects to be simultaneously monitored, without involving a high number of patients. We are proposing this double procedure for the parallel intraindividual evaluation of the vasoconstrictory action and the anti-allergic activity of topical steroids.

Notes: Assessment of patch lest results has been performed visually and using u lira sound in the U mode. A positive test site has a typical ultrasonographic appearance, presenting a uniform hypoechogenic area in the dermis. In this zone, the mean amplitude of ultrasound reflection peaks decreases, and the extension of this area increases, together with the intensity of the eczematous reaction. A close correlation has been shown between visual scoring, amplitude decrease and surface increase of the hypoecbogenic area. This technique seems to provide a reproducible System for the evaluation of patch tests.

Notes: 593 recruits selected by the Military Health Service as being healthy and without a history of present or previous dermatitis, or ocular refraction defects, were patch tested with the GIRDCA (Italian Research Group on Contact and Environmental Dermatitis) standard series, of these, 336 were also patch tested with substances used in the processing and dyeing of textiles and prick tested with 8 major allergens. 74 (12.5%) reacted to 1 or more substances. The most frequent sensitizes were: thimerosal (28 cases]. ammoniated mercury (7 cases), phenol-formaldehyde resin (6 cases], parabens, nicked and Disperse Red 17 (4 cases Each). 113 recruits reacted to 1 or more prick test allergens. We have demonstrated the importance of establishing such reference values in healthy groups for the correct evaluation of data collected from selected groups.

Notes: 139 workers from 3 ceramics factories underwent dermatological and allergological examination, using standard and occupational patch test series, in order to evaluate the prevalence of dermatitis and contact sensitization, to identify the most important sensitizing substances in the ceramics industry, and to correlate the results with possible risk factors such as atopy Hand dermatitis had affected 37% of the subjects examined. 27% of the workers were sensitized to 1 or more allergens. Of 52 subjects with dermatitis, 37% had allergic contact dermatitis and 63% irritant contact dermatitis. 18 subjects were found to be sensitized without showing any previous or present clinical symptoms. Atopy tended towards correlation with the overall incidence of dermatitis, though not with the prevalence of sensitization.