Protection afforded by controlled application of a barrier cream: a study in a workplace setting.

BACKGROUND: Skin protective creams (PCs) are used widely in industrial work environments to prevent irritant contact dermatitis. However, workplace studies remain equivocal in terms of their effectiveness, which may be partly owing to whether the PC remains on the skin. OBJECTIVES: To assess the practicability of using skin occlusion testing in a workplace as a method to determine whether PCs applied under controlled conditions can reduce skin damage against known irritants. This study also compares two methods of skin evaluation: clinical dermatological assessment and bioengineering techniques. METHODS: Daily occlusion testing for 1 h (over two consecutive weeks) was conducted in an engineering company on the volar forearm of 21 healthy volunteer engineers with sodium lauryl sulfate (SLS) and a PC that was used on site. The engineers conducted their normal work activities during the occlusion testing period. The skin areas tested were assessed using transepidermal water loss (TEWL), Chroma Meter and by visual dermatological scoring. RESULTS: Testing with PC and SLS together showed that PC does not prevent irritant contact dermatitis but significantly reduced skin damage compared with SLS alone (P < 0.01). The changes in skin were evident earlier with the biophysical measurements when compared with the dermatological assessment. CONCLUSIONS: Occlusion testing is a useful method for assessing the potential effectiveness of protective creams and can be used in a workplace without affecting work practices. TEWL and the Chroma Meter provide useful objective information and should be used in combination with dermatological examinations.

Cutaneous and systemic sequelae from exposure to 2-vinylpyridine.

We present the case of an employee of a chemical production factory who became sensitized to 2-vinylpyridine despite wearing full protective polyvinyl chloride clothing. He developed severe dermatitis at the site of contact, secondary eczematization over the flexures and periungual areas, as well as marked systemic upset. Pyridines are known sensitizers although this reaction pattern has not previously been described.

Photopatch testing of 1155 patients: results of the U.K. multicentre photopatch study group.

BACKGROUND: Photoallergic contact dermatitis can be difficult to diagnose if not appropriately investigated. Currently, the most common U.K. photoallergens appear to be sunscreen chemicals. The investigation of choice is photopatch testing (PPT), which is probably underused. In part, this is due to differences in methodology and results interpretation. OBJECTIVES: To conduct PPT using a group of sunscreen chemicals, defined indications and a standardized methodology including interpretation and relevance of reactions in patients attending for investigation at 17 centres across the U.K., Ireland and the Netherlands. METHODS: Patients (n = 1155) who fulfilled the inclusion criteria were investigated with PPT using sunscreen chemicals in addition to suspected topical products. Readings were taken at 24, 48 and 72 h following standardized ultraviolet A irradiation (5 J cm(-2)). The clinical relevance of any reaction was recorded. RESULTS: Of the 1155, 130 had allergic reactions (11.3%). Of these, 51 had photoallergy (PA) (4.4%), 64 had contact allergy (CA) (5.5%), and 15 patients had combined PA and CA (1.3%). Multiple PA was seen in some. The most common photoallergen was benzophenone-3 (27 reactions; 21%). Most reactions (60%) were clinically relevant. The most common indication for testing in patients found to have PA was a history of reacting to a sunscreen (41%). The other 59% had an exposed-site dermatitis/skin problem or a photodermatosis. Some centres (n = 8) performed readings after the standard 48-h reading, and an extra 32 PA and 22 CA reactions were detected, which were not evident at 48 h. A new photoallergen (octyl triazone) was detected in two patients. CONCLUSIONS: Sunscreen PA and CA are probably equally uncommon. Most reactions, of both reaction types, were relevant clinically. A large proportion of patients (59%) found to have PA was unaware of reacting to a sunscreen chemical, suggesting that PA should be considered as an explanation in any exposed-site dermatitis. Although this study focused on reactions at 48 h postirradiation, readings performed up to 96 h, while inconvenient, add value by detecting additional relevant responses. A previously unknown photoallergen was found, highlighting the need for awareness of novel photoallergens in the marketplace. A standardized PPT method not only encourages more use of this investigation, but also facilitates comparison of results between centres and so will improve our understanding of PA.

Severe adverse cutaneous reaction to insulin due to cresol sensitivity.

We present the case of an 80-year-old lady known to be sensitive to chlorocresol (4-chloro-3-methyl phenol) who developed severe erythrodermic exfoliative dermatitis with atypical features 2 weeks after commencing subcutaneous insulin. All medications except insulin were stopped, without major improvement. It was noted that the insulin contained m-cresol (m-methyl phenol) so a parabens-based insulin was substituted. There was a significant improvement in her clinical condition within 72 hr. Further patch and intradermal testing to the insulin and m-cresol was planned, but she developed a nosocomial infection and died. We hypothesize that the adverse cutaneous reaction was a systemic manifestation of cresol sensitivity, given the rapid clinical resolution on changing insulins and the previously demonstrated sensitivity to chlorocresol, particularly as cross-reactivity between different low molecular weight methyl phenols is documented. Local injection site reactions and systemic side-effects including nausea, diarrhoea and vomiting have previously been reported with cresol-containing insulins, although to our knowledge, this is the first reported case of a severe cutaneous reaction. It is important to be aware of m-cresol as a potential allergen, as it is contained in most commercially available insulins.

Sensitisation to natural rubber latex: an epidemiological study of workers exposed during tapping and glove manufacture in Thailand.

OBJECTIVES: To estimate the prevalence of sensitisation to natural rubber latex in latex tappers and latex glove factory workers, and to relate this to airborne exposure to latex. METHODS: Five hundred workers employed in three latex glove factories, 314 tappers, and 144 college students (control group) were studied. The workers in the glove factories were classified into three exposure groups; high, moderate, and low. Personal exposures to natural rubber latex aeroallergens were measured by immunoassay. Symptom questionnaires and skin prick tests with latex allergens (Stallergènes 1:200 w/v) and other common environmental allergens were performed. The criterion for positivity was a wheal reaction at least 3 mm in diameter greater than that to a diluent control. RESULTS: The geometric mean (GM) concentration of latex in air was 15.4 microg/m(3) for those employed in glove stripping, glove inspections, and packing of powdered gloves. The moderate exposure glove manufacturing group and the tappers had GM concentrations of 2.3 and 2.4 microg/m(3) respectively, compared with United Kingdom users of latex powdered gloves,who had GM concentrations of 0.5 microg/m(3). The prevalence of sensitisation to latex in the tappers and latex glove factory workers was 1.3% and 1.7% respectively. No positive cases were found among the college students. Workers who showed a positive skin prick test to latex were more likely to be atopic. Work related respiratory and dermatological symptoms were found in about 20% of each population studied, but were not related to the presence of positive latex prick tests. CONCLUSIONS: This study suggests that in the Thai latex industries, latex sensitisation is rare despite high concentrations of airborne exposure and is less prevalent than in the healthcare sector in Europe where skin exposure is greater.