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Notes: This study evaluates the influence of mineral oil and linoleic-acid-containing emulsions on the skin vapour loss (SVL) of detergent-induced irritant skin reactions. During a period of 2 weeks, 2 × 45 min applications of a sodium lauryl sulphate solution of low molarity were performed on the forearm of 9 volunteers. In the same period, a standard amount of each emulsion was applied on the induced irritant skin reactions, 3 times each day. The effect of the emulsions on the barrier function of the skin was evaluated by means of SVL measurements. The emulsion based on mineral greases significantly reduced SVL values during both weeks, possibly because of an occlusive effect. The emulsion with 15% of linoleic acid significantly reduced SVL values during the 1st week but not during the 2nd week. The emulsion with 38% of linoleic acid did not reduce SVL values at all.

Notes: It is of great importance to find ways to lower the incidence of chronic irritant contact dermatitis. In this process, it is crucial to have insight in the factors that can predict irritancy. This review offers a survey of recent findings in the field of skin irritancy testing, discussed in the context of renowned, older work. Extrinsic and intrinsic factors that may determine the outcome of irritancy testing in the human skin model are considered. In recent decades, there has been increasing interest in factors influencing the development of occupational dermatitis by means of prospective cohort studies. This promising new area of investigation is discussed separately.

Notes: The aim of the study was to test the irritancy of 6 antiseptics in an open exposure model. The following agents were tested in their normal use concentrations using open exposures. 2 × daily for 4 days in 20 subjects: chlorhexidine 4%(CH), chlorhexidine 0.5% in ethanol 70%(CE), ethanol 70%(ET), iodine 1% in ethanol 70% (IE), povidone-iodine 10% (PI) and sodium hypochlorite 0.25% (SH). Responses were evaluated by visual scoring, subjective irritancy scoring, stratum corneum hydration (Corneometer), transepidermal water loss and laser Doppler flowmetry. Exposure to SH had to be discontinued after 4 applications because of severe subjective irritation. The same held true for IE (7 applications), whereas the other agents were exposed 8 ×. All evaluation methods showed SH to be significantly more irritating than IE, which was in turn more irritating than CH. CE, ET and PI. Thus, it can be concluded that CH, CE, ET and PI were nonirritating in this open exposure model.

Notes: This report reviews the clinical and hisiopathological reactions caused by sodium lauryl sulfate (SLS), and the non-invasive methods that can characterize these reactions. Furthermore, SLS exposure techniques and factors that may influence the outcome of these exposures are discussed. Finally, guidelines are introduced for each exposure technique in order 10 have a uniform approach to SLS jesting in man. Since different study aims warrant different testing conditions, we have proposed 2 categories, namely susceptibility testing and provocative testing, tailored to the aim with which the study is performed.

Notes: Discrepancies between the one-time patch test and the wash test regarding the ranking of irritancy of detergents have been found in the literature. The aim of the present study was to investigate the concordance of irritancy rank order of 4 anionic detergents tested by 3 different exposure methods, namely one-time occlusive, repeated short-time occlusive and repeated short-time open tests. These detergents were sodium cocoyl isethionate (ISE), sodium lauryl sulfate (SLS), soap and disodium lauryl 3-ethoxysulfosuccinate (SUC). The reactions were evaluated by visual scoring and by transepidermal water loss (TEWL) measurement. When scored visually, the rank order in the one-time test was: SOAP≥SLS≥ISE〉SUC. The other test methods yielded a different order: SLS〉ISE≥SOAP〉SUC. A similar rank order was obtained with TEWL measurement for all exposure methods. Generally, the concordance among the different exposure methods was high when evaluated by TEWL. The concordance was lower when evaluation was performed by visual scoring. The present study demonstrates that the choice of exposure model and evaluation method may be important variables influencing the outcome of irritancy testing. It is proposed that the repeated open test is the best way to simulate most in-use situations where the uncovered skin is exposed to detergents. The repeated occlusive test or the one-time patch test may be better to simulate situations in which the skin is occluded after irritation by detergents.

Notes: In studies on atopic dermatitis (AD), different scoring systems are used to evaluate the severity of the disease. The objective of this study was to investigate agreement between observers in the assessment of the overall severity of AD, and interobserver variation in the assessment of severity of AD for each scoring item separately, using the Simple Scoring System (SSS), the Scoring Atopic Dermatitis (SCORAD) index, and the Basic Clinical Scoring System (BCSS), and, furthermore, to investigate agreement between these three scoring systems in the assessment of the overall severity of AD. Eighty-two patients (42 male) with AD, mean age 13.4 years (range 0.2−67.0), were included. Agreement between observers in assessing the overall AD severity scores, and interobserver variation in assessing AD severity of each scoring item separately were determined in 34 of these 82 patients by two physicians scoring the severity of AD by the three scoring systems. To determine agreement between the scoring systems, one physician scored the severity of AD in all patients with the three scoring systems. Agreement between observers and agreement between the three scoring systems was calculated by Cohen's kappa (κ) and by the measure of agreement according to Bland & Altaian. κ〉0.4 represents fair agreement; κ〉0.75 excellent agreement. In addition, interobserver variation for each scoring item separately was calculated by the Wilcoxon signed rank test. The mean differences (d) and the limits of agreement (d±2 SD of the differences) between observers by the SSS and the SCORAD were −0.82±5.58 and −0.28±7.49, respectively. κ between observers for the BCSS was 0.90 (95% CI 0.79−1.03). By the SSS, significant interobserver variation was found in assessing the severity of excoriations (P=0.02) and scales (P=0.02). By the SCORAD, significant interobserver variation was found in assessing the severity of edema/papulation (P=0.04), erythema (P=0.04), and excoriations (P=0.01). No significant interobserver variation was found in assessing the extent of AD. The mean difference and the limits of agreement between the SSS and the SCORAD were −4.17±9.52. k between the SSS and the BCSS was 0.21 (95% CI 0.09−0.33), and k between the SCORAD and the BCSS was 0.38 (95% CI 0.26−0.51). We found good agreement between observers assessing the overall severity of AD in the lower and higher scoring rates by the SSS and the SCORAD, and excellent agreement by the BCSS. Significant interobserver variation was found on the isolated intensity items scales, excoriations, edema/papulation, and erythema. We found poor agreement between the three scoring systems in assessing the overall severity of AD, indicating that the SSS, the SCORAD, and the BCSS cannot be used interchangeably to assess the overall severity of AD.

Notes: The pathogenetic role of house-dust mites (HDM) in atopic dermatitis (AD) remains controversial, mainly because there is no common agreement on a provocation test that mimics ordinary exposure to HDM. This is related to the lack of knowledge of the mechanism of how HDM allergens enter the body. Theoretically, there are two possible routes: directly through the epidermis, or by inhalation. In “atopy patch testing”, a concentrated HDM suspension is tested on the skin under occlusion. This method is frequently used as a model of the epidermal route. The clinical relevance of this method as a provocation test for AD is discussed. As opposed to atopy patch testing, we describe another method, namely, “allergen inhalation testing”, as a model of the respiratory route. Twenty patients with AD underwent bronchial provocations with HDM extract in a double-blind, randomized, placebo-controlled study. In nine out of 20 AD patients, bronchial challenge with HDM evoked skin symptoms. All patients with HDM-induced dermatitis had a history of asthma, and as a group they had a higher mean total log-transformed IgE level than the “negative skin responders”. Thus, the respiratory route may be relevant in the provocation of AD in a subset of AD patients and may represent an appropriate model of provocation in these patients. Furthermore, the role of HDM in urticaria and allergic rhinitis is discussed.

Notes: The irritant potency of soap (sodium laurate, LAU) as opposed to other anionic detergents is not uniformly agreed upon. The aim of the study was to compare the irritancy of sodium laurate with that of sodium laurylsulphate (SLS), sodium cocoyl isethionate and disodium lauryl 3-ethoxysulphosuc-cinate by means of a 4-day repeated open exposure model in order to achieve a more realistic mimicry of daily practice.〈section xml:id="abs1-2"〉〈title type="main"〉Methods: The effects of the exposures were evaluated by: a) number of fulfilled exposures, b) visual score after exposures, and c) transepidermal water loss (TEWL) after exposures.〈section xml:id="abs1-3"〉〈title type="main"〉Results: In the majority of subjects, exposure to LAU had to be stopped because of burning sensations, erythema and/or scaling. The number of fulfilled exposures to LAU was lower than that of SLS. The other agents were tolerated very well. These less irritative agents had much lower visual scores and TEWL values after the repeated exposures compared with LAU and SLS.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions: The explanation for the irritant nature of LAU in the present study might be the type of alkyl chain length distribution. Its 12-carbon chain content was ≤ 99%, and this agent can therefore be designated as pure sodium laurate. The same holds true for SLS. In daily practice, however, soap is a mixture of different – less irritant – chain lengths. Therefore, these findings cannot be extrapolated to commercially available soap bars.