Skin reactivity to sodium lauryl sulfate in patients with respiratory atopy.

BACKGROUND: No literature data are available on the skin reactivity of patients with respiratory atopy alone. OBJECTIVE: Our purpose was to assess skin reactivity to detergents in patients with allergic asthma, rhinitis, or both. METHODS: The skin of the volar aspect of the forearm of 19 subjects with allergic asthma or rhinitis (or both) was challenged with a single exposure to 0.5% sodium lauryl sulfate. The skin response was evaluated by transepidermal water loss (TEWL), capacitance, and echogenicity measurements. Results were compared with those obtained in 19 patients with atopic dermatitis (AD) and 20 healthy subjects. RESULTS: In patients with AD preexposure TEWL values were higher than in healthy subjects, whereas capacitance values were lower. In this patient group, postexposure TEWL, capacitance, and echogenicity values showed more pronounced variations than in healthy subjects. Conversely, in patients with allergic asthma or rhinitis (or both), both baseline and postexposure TEWL, capacitance, and echogenicity values were similar to those in healthy subjects. CONCLUSION: Patients with respiratory atopy without AD do not have the functional abnormalities characteristic of skin affected by AD, either under baseline conditions or after exposure to sodium lauryl sulfate.

Ultrasound description and quantification of irritant reactions induced by dithranol at different concentrations. A comparison with visual assessment and colorimetric measurements.

Dithranol (D) is used as a therapeutic topical agent to treat psoriasis, although it produces inflammation and staining of skin and clothing. D-induced irritation has been evaluated by visual scoring and by bioengineering techniques, evidencing modifications of the inflammatory parameters, but no alterations of the skin barrier. The aim of our study was to evaluate the irritant reactions induced by D using ultrasound, and to compare the B-scanning data with visual assessments and colorimetric measurements. 13 healthy women underwent 2, 3-h patch tests with, respectively, 0.02% and 0.1% D in white petrolatum and 1 24-h patch test with 2% sodium lauryl sulfate (SLS). For assessing skin reactions, clinical judgement, colorimetry and echography were employed. Echographic images were evaluated by skin thickness measurements and segmentation procedures, using an 0-30 interval, marking the hyporeflecting areas in the dermis, and a 201-255 interval, assessing the hyperreflecting components of the image (both epidermal and dermal). In all subjects, D produced uniform reactions, the intensity varying according to concentration. Both echographic parameters of inflammation (skin thickness and 0-30 areas) showed an increase at all times of assessment. The 201-255D/0-30 pixel ratio, describing the distribution of dermal edema, indicated that strong inflammatory reactions, such as those caused by the application of 0.1% D, are accompanied by edema in the lower portion of the dermis. Finally, in contrast to SLS reactions, where a 24-h reduction in epidermal reflectivity was observable, D reactions appeared with an accentuation of the 201-255 epidermal band at 24-96-h examinations.

Prevalence of contact allergy to non-disperse azo dyes for natural fibers: a study in 1814 consecutive patients.

5 non-disperse azo dyes, used for colouring natural fibers, were added to the standard patch test series, as 5% pet. preparations. 1814 consecutive patients attending the patch test clinic were patch tested, of whom 16 (0.88%) reacted to the newly added dyes: 8 to Direct Orange 34, 5 to Acid Yellow 61, 2 to Acid Red 359 and 1 to Acid Red 118. On the basis of clinical history and results of patch tests with pieces of fabrics, contact sensitization to non-disperse azo dyes seemed to be related to the appearance of skin lesions at least in 8 subjects. We conclude that systematic exploration of the sensitizing potential of textile dyes, selected after careful investigation, can provide additional information on the frequency of occurrence of textile dye dermatitis, supporting individual investigation in sensitized subjects.

Capacitance, transepidermal water loss and causal level of sebum in healthy subjects in relation to site, sex and age.

Summary 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.

Instrumental evaluation of subclinical responses to 0.05% NiSO(4) patch tests.

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.