Considering the scarcity of dermatologic resources in many parts of the world, self-testing by patients is not only of interest for internal medicine but also for dermatology. In this open, nonrandomized, multicenter diagnostic trial involving subjects with suspected contact sensitization to nickel and/or a fragrance mix, we assessed the agreement of self-testing by subjects with readings made by dermatologists. The self-test product (Nixema^TM) is based on Thin-Layer Rapid Use Epicutaneous Test (TRUE Test®) technology. One hundred and sixty-five subjects self-tested the ready-made patch-test product. The test was applied for 48 h and then read after 3 or 4 days. It was also evaluated independently by experienced dermatologists after 3 or 4 days. In the 162 evaluable subjects, the proportion of agreement for both allergens together was 89.5% [95% confidence interval (CI) 83.7-93.8], the sensitivity was 97.5 % (95% CI 86.8-99.9) and the specificity was 86.9% (95% CI 79.6-92.3). Cohen's kappa was also high at 0.749 (95% CI 0.637-0.862). Discrepancies between the subjects' readings and the dermatologists' readings were mainly due to the subjects interpreting reactions of ‘irritant' or ‘doubtful' as ‘positive'. Apart from itching and burning sensations and tape irritation, no side effects were observed. In conclusion, this study showed a high rate of agreement between the self-reading of the upper arm and the readings made by the dermatologists. The upper arm proved to be an appropriate area for self-testing. Self-testing may improve the screening for contact sensitization for patients, particularly where dermatologic health resources are scarce.

To understand the mechanisms involved in immunological tolerance to skin-associated proteins, we have developed trangenic (Tg) mice that express a model self antigen, membrane-bound ABSTRACTS 125 FS01.3 Disperse (yes), orange (yes), 3 (no): what do we test in textile dye dermatitis?Para-phenylenediamine (PPD), an arylamine dye, is a strong allergen causing allergic contact dermatitis. Cytokines such as TNF-a and IL-1beta are key mediators in the initiation of this reaction. Both cytokines are predominantly produced by stimulated monocytes and macroghages. We investigated the responses of PPD and Bandrowski's base (BB), an autoxidation product of PPD in human monocytes. We isolated monocytes from healthy volunteers and incubated them with the allergens. TNF-a and IL-1beta mRNA expression and protein levels were estimated after 45 min, 2 h, 4 h and 24 h after allergen contact. IL-1beta and TNF-alpha were measured in cell culture supernatants by ELISA (n ¼ 7) and mRNA expression was determined by real-time RT-PCR. We found that PPD reduced TNF-a protein secretion by 20-69.9% (n ¼ 6). Further, IL-1beta levels were decreased by 44-98%. The same tendency was found studying IL-1beta and TNF-a mRNA steady state levels (n ¼ 3; 1 h incubation). These effects were substance-specific and not found for PPD derivatives nor for the autoxidation product BB. These findings suggest that PPD may specifically modify immune responses by directly infering with the cellular proinflammatory cytokine network.