Allergy patch test reading from photographic images: disagreement on ICDRG grading but agreement on simplified tripartite reading.

BACKGROUND/AIMS: The International Contact Dermatitis Research Group (ICDRG) system for clinical scoring of allergic patch test reactions is well established in clinical dermatology for detailed scoring of allergic reactions. The degree of redness and the presence of swelling, papules, vesicles and bullae are assessed based on visual examination and palpation of reactions. In photographic assessment used in research and tele-dermatology, the scoring is solely based on visual examination of photos. The aim of the study was to evaluate inter-expert variation in patch test reading using photographic images, with ICDRG reading as a reference. MATERIAL AND METHODS: Five experienced senior dermatologists each scored 55 positive patch test reactions from 16 slides in an office environment. The slides showed pictures of patch tests with different allergens. The scoring system by ICDRG with six categories for scoring was used. RESULTS: The five dermatologists performed the scoring very differently. When the scoring system was simplified to a tripartite scoring system, the scoring was performed almost similarly by the five clinicians. CONCLUSION: Based on the present results, it is proposed that the number of scoring categories should be minimized and simplified into negative (including doubtful) reactions, positive reactions and irritant reactions. Such simplified tripartite reading is proposed for research purposes and for tele-dermatology, when scoring is based on photographic images.

Biophysical assessment of persistent effects of moisturizers after their daily applications: evaluation of corneotherapy.

BACKGROUND: Although effective moisturizers can improve xerotic skin changes immediately, their effects are only transient, because the materials applied to the stratum corneum (SC) are easily shed from the skin surface by the daily desquamation process. However, there are a few lines of clinical as well as experimental evidence suggesting that, once application of effective moisturizers is repeated daily, they may produce persistent effects without being influenced by the desquamation of the skin surface. If we can expect such pharmacological effects by simple repeated applications of moisturizers on the skin surface, it will provide a great motivation for the introduction of corneotherapy into the treatment of xerotic skin problems. OBJECTIVE: This study was designed not only to confirm the feasibility of corneotherapy but to propose a practical method to assess such long-lasting effects of moisturizers by using biophysical methods. METHODS: We conducted applications of various moisturizers twice daily to different areas of the flexor surface of the forearms for the initial 5 days of the first week. Thereafter, we performed biophysical measurements of the SC of these areas in the second week, namely 3, 5 and 7 days after their last applications. RESULTS: Daily repeated applications of moisturizers did not induce any change in the water barrier function of the SC or in the size of desquamating corneocytes, a parameter for turnover rate of the SC. However, they substantially increased high-frequency conductance, a parameter for the hydration state of the skin surface, for several days in both normal individuals and patients with atopic xerosis, although the lasting effects were shorter in the latter. The obtained data enabled us to rank the efficacy of moisturizers either according to the duration of the lasting effects or the magnitude of an increase in the hydration levels of the SC. CONCLUSION: The present results confirmed the feasibility of corneotherapy, in which even simple application of moisturizers targeted at the SC can produce unexpected persistent clinical effects after their repeated treatments. The method described in this study constitutes a practical assay system to evaluate the efficacy of topical agents used for dry skin problems objectively and quantitatively.

Comparative study of the efficacy of various moisturizers on the skin of the ASR miniature swine.

The skin of the back of the ASR hairless miniature swine shows a rough and scaly fissured appearance. Clinically it resembles that of ichthyosis vulgaris or senile xerosis in humans. By using the skin of this animal, we developed an assay system to evaluate the efficacy of different moisturizers. The study was carried out in winter months from January to March. To establish this system, we studied various topical agents including such ordinary emollients as petrolatum and 10% salicylic acid in petrolatum as well as those available as pseudodrugs from cosmetic companies or prescription drugs from pharmaceutical companies such as heparinoid- containing creams (w/o and o/w) and 10% urea creams. Applying 0.01 g of each agent to 7 randomly selected skin areas (2x2 cm(2)) on the back of a 6-month-old swine once daily for various periods of time, we measured high-frequency conductance, the parameter for the hydration state of the skin surface. As a result, we have established a simple assay system. It consists of applications of topical agents once daily for 5 days from Monday to Friday in the first week and of subsequent measurement of the skin surface hydration state once every week. Evaluation measurements were performed from day 14 to day 21 depending upon their moisturizing effects. We found that heparinoid-containing creams exerted highly effective moisturizing effects on the dry pig skin that lasted even over 3 weeks after discontinuation of the treatments that were carried out for the first 5 days.

Functional analysis of the stratum corneum of scalp skin: studies in patients with alopecia areata and androgenetic alopecia.

Because of the presence of thick long hairs on the scalp, little information is available concerning the functional characteristics of the stratum corneum (SC) of scalp skin. We therefore conducted a functional study of the SC of lesional scalp skin of patients with alopecia areata and of patients with androgenetic alopecia. We compared the scalp with the cheek and the flexor surface of the forearm (volar forearm). The water barrier function of the scalp SC of both patient groups, in terms of transepidermal water loss (TEWL), was almost comparable to that of the volar forearm, and was far better than that of facial skin. However, hydration of the scalp skin surface, as evaluated by measurement of high-frequency conductance, was markedly higher than that of facial skin, and showed significantly higher values than the volar forearm. These characteristics seem to be dependent, at least to some extent, on the amount of sebum-derived skin surface lipids because these were abundant on the scalp skin. Moreover, removal of skin surface lipids led to a significant decrease in skin surface hydration. The superficial corneocytes, the size of which reflects the proliferative activity of the epidermis, were substantially smaller on the scalp than on the volar forearm but significantly larger than on the cheek. These findings suggest that the rate of turnover of the scalp epidermis is intermediate between that of the facial and volar forearm epidermis. We conclude that the SC of the scalp skin in humans is functionally distinct from that of the face and extremities.