Addressing the conundrums of p-phenylenediamine hair dye allergy by applying Friedmann's principles of contact sensitization.

In the first conundrum, permanent hair dyeing involves the use of aromatic amines such as p-phenylenediamine (PPD), whose oxidation is pivotal to the dyeing process, but also generates potent allergens. Despite prolonged efforts by industry to search for safer alternatives, hair dyeing is still reliant on this type of aromatic amine. In the second conundrum, patch testing with 1% PPD remains the most useful screen for hair dye contact allergy. However, there is a very small but real risk of actively sensitizing the patient. Lowering the PPD concentration below 1% significantly reduces test sensitivity and diagnostic utility. Here, we argue that by applying Friedmann's principles of contact sensitization each conundrum can be addressed from a new perspective. These principles indicate that, when the exposed area of skin is small (<1 cm2 ), induction of contact allergy is sharply reduced, whereas elicitation of allergy is unaffected. Careful reflection on this principle suggests that we can predict where hair dye sensitization is most likely to occur, indicates a strategy to reduce the chance of contact sensitization occurring in consumers as a result of hair dyeing, and how we might mitigate the risk of active sensitization resulting from diagnostic patch testing.

Silicone gel enhances the efficacy of Er:YAG laser treatment for atrophic acne scars: A randomized, split-face, evaluator-blinded, placebo-controlled, comparative trial.

BACKGROUND: The effect of topical silicone gel has been studied to prevent scars from burn, postoperative wound and to treat hypertrophic scars. No previous studies have been done to evaluate the efficacy of topical silicone gel on atrophic acne scars. MATERIAL AND METHODS: Nineteen patients were treated with three sessions of ablative Er:YAG laser with 1-month intervals. Following each laser treatment, the randomlyassigned silicone gel or placebo was applied in split-face manner. Objective assessments, which included roughness, smoothness, hydration, transepidermal water loss were measured at baseline and prior to each treatment. Subjective assessments by dermatologists and subjects were done at baseline and 1 month after last laser treatment. RESULTS: The laser treatments were well tolerated and resulted in clinical improvements. Topical silicone gel treatment resulted in significantly less roughness at weeks 4 and 12 compared with placebo (p < 0.05). CONCLUSION: Adding topical silicone gel to ablative Er:YAG laser treatment may provide additional benefits in improving acne scars.

Diagnosing Allergic Contact Dermatitis Through Elimination, Perception, Detection and Deduction.

Several authors have commented upon the skills of detection required in making a diagnosis of allergic contact dermatitis. Here, we emphasise the search for clues in a systematic manner. We describe four stages as part of a systematic method for diagnosing allergic contact dermatitis. Firstly, elimination (or inclusion) of non-allergic diagnoses. Secondly, perception: the pre-patch test diagnosis and the 'three scenarios' principle. Thirdly, detection: optimising the sensitivity of the patch test process. Fourthly, deduction: diagnosing allergic contact dermatitis by associating the dermatitis with the allergen exposure. We further compare and contrast the pre-patch test history and examination with the markedly different one ('microhistory' and 'microexamination') used after patch testing. The importance of knowledge of contact dermatitis literature is emphasised with a review of recent publications. Finally, we also highlight the use of contact allergy profiling as an investigative tool in the diagnosis of allergic contact dermatitis.

Anterior Tragal Crease Is Associated With Atherosclerosis: A Study Evaluating Carotid Artery Intima-Media Thickness.

The utility of the ear crease sign, anterior tragal crease (ATC), as a marker of atherosclerosis is yet to be established. The intima-media thickness of the common carotid artery (IMT-CCA) has been used as a noninvasive surrogate marker for atherosclerosis. History of traditional risk factors for atherosclerosis was obtained from 147 volunteers; ear examination was also performed and venous blood was drawn for laboratory analysis. The volunteers then underwent an ultrasonography measurement of the IMT-CCA. In univariate analysis, presence of ATC, age, underlying hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular disease, cigarette smoking, low-density lipoprotein, and high-sensitivity C-reactive protein were significantly associated with the IMT-CCA. Further multivariate analysis confirmed a significant association between the presence of ATC and IMT-CCA, when adjusted for other factors (adjusted ßATC = .010, 95% confidence interval: 0.0021-0.019). Anterior tragal crease is a potential clinical sign that can predict atherosclerosis. The sign is easily recognizable and may help health-care professionals to identify those at risk of atherosclerosis, especially in people with no clinical signs of the disease.

Proposed ICDRG Classification of the Clinical Presentation of Contact Allergy.

The International Contact Dermatitis Research Group proposes a classification for the clinical presentation of contact allergy. The classification is based primarily on the mode of clinical presentation. The categories are direct exposure/contact dermatitis, mimicking or exacerbation of preexisting eczema, multifactorial dermatitis including allergic contact dermatitis, by proxy, mimicking angioedema, airborne contact dermatitis, photo-induced contact dermatitis, systemic contact dermatitis, noneczematous contact dermatitis, contact urticaria, protein contact dermatitis, respiratory/mucosal symptoms, oral contact dermatitis, erythroderma/exfoliative dermatitis, minor forms of presentation, and extracutaneous manifestations.