No abstract

Chemical ultraviolet (UV) filters have, over the last few decades, been increasingly used not only in conventional sunscreen products but also in many cosmetics and toiletries. Allergic contact dermatitis as well as photoallergic contact dermatitis reactions have been well documented as a consequence of such use. Over a 3-year period, we recorded the number of positive patch test reactions to a selection of chemical UV filters that we added to our usual cosmetics/facial series. Our objective was to investigate whether any of these filters produced significant numbers of positive patch test results in the absence of photostimulation. Our results show that not only did benzophenone 4 (2-hydroxy-4-methoxybenzophenone-5-sulphonic acid: sulisobenzone) produce significantly more positive patch test results than the other UV filters that were tested, but also it was the third most frequently positive result overall. Our findings would support the inclusion of benzophenone 4 when patch testing to investigate likely contact dermatitis from cosmetics and toiletries.

No abstract

Temporary 'black henna' tattoos are an increasingly popular body decoration with a growing incidence of associated adverse events. We report the case of a 14 year old girl presenting with an acute allergic contact dermatitis to hair dyes. Some years previously she had a 'black henna' tattoo with prior application of a tacky transfer to the skin to outline the design followed some days later by an acute localised blistering reaction. Patch testing to an extended British Contact Dermatitis Society standard series showed relevant positive reactions to paraphenlyenediamine (PPD) and thiuram mix, as well as to several of the azo disperse dyes. We went on to perform prick testing to natural rubber latex (NRL), showing a positive reaction to the commercial HEP 100 concentration. We propose that through the initial acute reaction caused by PPD in the 'black henna' our patient was not only sensitized to PPD, but also to thiuram and natural rubber latex which may have been present in the tacky transfer applied prior to 'tattooing.' We would add that temporary 'black henna' tattoos may have more important consequences than previously thought on patients' future health by sensitization to NRL.

Benzalkonium chloride (BAK) is an acknowledged irritant but has also been identified as a cause of allergic contact dermatitis. The antiseptic bath emollient Oilatum Plus (Stiefel, High Wycombe, U.K.) contains a relatively high concentration of 6% BAK. We describe six patients who presented with flexural eczema, particularly involving the anogenital area, who had a history of using Oilatum Plus. Patch testing showed all six to have a type 4 allergy to BAK as well as other allergens. Avoidance of Oilatum Plus led to a resolution of the flexural eczema in each case.