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Background: Neomycin is an aminoglycoside antibiotic that may cause contact allergy. It was withdrawn as a medicine for human use in Denmark in October 2009 but is still found in some vaccines. Objectives: To identify time trends in contact allergy to neomycin in the period from 2000 to 2023. Methods: A cross‐section study of patients ≥18 years consecutively patch‐tested with neomycin sulfate (20% in pet.) at Gentofte Hospital, Denmark, during the period 2000–2023 was conducted. Results: The overall prevalence of contact allergy to neomycin was 1.4%. The prevalence was significantly lower in the period '2010–2023' (1.2%) than in '2000–2009' (1.8%) (p < 0.005). Contact allergy to neomycin was significantly positively associated with facial dermatitis and age >40 years, and significantly negatively associated with occupational dermatitis and hand dermatitis. No changes in sex, occupational dermatitis, atopic dermatitis, hand dermatitis, leg dermatitis, facial dermatitis, or age > 40/≤40 (the MOAHLFA‐index) were identified when comparing neomycin contact allergic‐patients in the two periods '2010–2023' and '2001–2009'. Conclusion: Neomycin is a rare cause of contact allergy in Denmark with a significantly lower prevalence following its withdrawal as a medicinal product for human use in Denmark in 2009. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Rubber gloves contain rubber accelerators that may cause contact allergy. The content of sensitising rubber accelerators in contemporary rubber gloves is not well known.Identify and quantify the content of rubber accelerators in disposable rubber gloves.Fifty‐one gloves of 49 different brands were collected. Forty‐eight of the gloves were disposable and three re‐usable. The gloves were analysed for their content of sensitising rubber accelerators, that is, zinc dithiocarbamates, thiurams, thiazoles/benzothiazoles, diphenylguanidine, and thioureas by high‐performance liquid chromatography.Rubber accelerators were identified in 43/48 (90%) of the disposable gloves. In total, 39 gloves contained zinc dibutyldithiocarbamate (ZDBC) (0.18–1.96 mg/g), 34 zinc diethyldithiocarbamate (ZDEC) (0.032–2.78 mg/g), three zinc dibenzyldithiocarbamate (0.65–1.4 mg/g), one zinc dimethyldithiocarbamate (0.23 mg/g), and one 1,3‐diphenylguanidine (0.21 mg/g). 2‐cyanoethyl dimethyldithiocarbamate (CEDMC) was identified in three gloves (<0.052 mg/g). The one glove labelled as accelerator free contained ZDBC (1.07 mg/g). Only few glove packages had the specific content of rubber accelerators labelled.The most frequent rubber accelerators in rubber gloves are ZDEC and ZDBC. Accelerator‐free gloves may contain rubber accelerators. Full labelling of rubber gloves is needed and producers should be sure not to falsely claim that the rubber gloves are free of rubber accelerators. [ABSTRACT FROM AUTHOR]

Background: The use of methylisothiazolinone (MI) as a preservative in cosmetic products caused an alarming increase in MI contact allergy across Europe in the 2010s. This was followed by regulations of use with a total ban on leave‐on (implemented in 2017) and reduced use concentrations in rinse‐off cosmetics (2018). Objective: To follow‐up on the prevalence of contact allergy to MI and the related benzisothiazolinone (BIT) and octylisothiazolinone (OIT) in consecutively patch‐tested patients in Europe. Methods: A cross‐sectional audit following the design of two previous audits on MI contact allergy from 1 May 2022 to 31 October 2022 included all patients patch tested with the European baseline series, including or supplemented with MI, BIT and OIT across 10 departments in eight European countries. Results: A total of 2554 patients were consecutively patch tested with the three isothiazolinones during the study period. The prevalence of MI and BIT contact allergy was 2.9% (95% confidence interval [CI]: 2.3%–3.7%; range 1.1%–5.8%) and 3.1% (95% CI: 2.4%–3.9%; range 0.0%–6.6%), respectively; that of OIT was 0.7% (95% CI: 0.4%–1.1%; range 0%–3.2%). Rinse‐off cosmetic (73.3%) and leave‐on cosmetic products (13.3%) were still associated with eliciting allergic contact dermatitis to MI. Conclusion: We confirmed a positive impact of regulatory measures on the prevalence of MI contact allergy in Europe, which halved compared to 2015. However, our data suggest that consumers may still be exposed to older cosmetic products containing MI. BIT has superseded MI in causing contact allergy, despite not being allowed for use in cosmetic products. [ABSTRACT FROM AUTHOR]

This article discusses a study conducted at Gentofte Hospital in Denmark on contact allergy to textile dye mix (TDM) in eczema patients. The study analyzed historical data from 2015 to 2023 and found that the overall prevalence of contact allergy to TDM was 2.3%. There was no significant trend in the prevalence of contact allergy to TDM over the study period. The study also found that leg eczema was significantly associated with contact allergy to TDM. The most prevalent dye causing contact allergy in TDM allergic patients was Disperse Orange 3 (DO 3), and there were concomitant reactions between DO 3 and another allergen called PPD. The authors suggest excluding DO 3 from TDM and introducing a new version of TDM without DO 3. However, they also propose temporarily including DO 3 in supplementary standard series for better surveillance. [Extracted from the article]

Background: Rubber accelerators are used in the production of rubber gloves and may cause contact allergy. Objectives: To estimate long‐term trend and prevalence of contact allergy to rubber accelerators for a 30‐year period in Denmark, high‐risk occupations, and exposures. Methods: Data from all patients with contact dermatitis consecutively patch tested at the department of Skin and Allergy Gentofte hospital with the rubber accelerators from the European baseline series (EBS) from 1990 to 2019, were analysed. Further, patients under suspicion of rubber accelerator contact allergy were additionally patch‐tested with rubber accelerators from the specialised rubber series from 2005 to 2019 and these were additional extracted. Results: The overall prevalence of contact allergy to one or more of the rubber accelerators from the EBS series was 2.7% with a significant decline in the first 12‐years, followed by a stable frequency in the past 18‐years. Associations with occupational contact dermatitis, hand dermatitis, and leg/foot dermatitis were found. Wet‐work occupations were most often affected and gloves the most frequent exposure. Conclusions: Contact allergy to one or more of the rubber accelerators from the EBS is frequent and has been unchanged for several decades, which calls for prevention. [ABSTRACT FROM AUTHOR]

Numerous studies have focused on emerging allergens causing contact allergy and allergic contact dermatitis in eczema populations and the general population, whereas only a few European multicenter studies systematically manage to detect prevalence rates of various contact allergies over time in eczema populations. Contact allergy is a life-time condition, which may lead to allergic contact dermatitis in individuals who do not manage to avoid exposure to the ascertained allergen in question. It is therefore of utmost importance that clinicians and dermatologists have sufficient knowledge on common allergens causing contact allergies in the general and working population. This review aimed to highlight the newest knowledge of frequent allergens of clinical importance. Literature was sought from the Pubmed™ database, Google™ scholar and textbooks. On the basis of the literature within the last 5 years, a comprehensive review of methylisothiazolinone, chromium, cobalt, rubber accelerators and fragrance ingredients were conducted. Of each allergen we discuss in detail the temporal trend of prevalence, source of exposure, clinical manifestation of allergic contact dermatitis and legislative measurements on how to regulate the exposure. [ABSTRACT FROM PUBLISHER]

Contact dermatitis in healthcare workers is a world wide problem. We conducted a retrospective observational study of the patch-test results of 1,402 healthcare workers and 1,402 matched controls with contact dermatitis who were treated at 3 hospitals departments in Denmark between 2007 and 2014. The primary objective was to determine whether healthcare work was associated with contact allergy to thiuram mix, used as a rubber accelerator ib rubber protective gloves. Unadjusted univariate analyses revealed that healthcare work was significantly associated with occupational contact dermatitis and hand dermatitis. Contact allergy to thiuram mix was more common in healthcare workers, and was significantly associated with having occupational contact dermatitis, hand dermatitis and older age. In conclusion, we report here a potential problem of contact allergy to thiurams in healthcare workers with contact dermatitis. Legislative authorities may in the future focus on the use of rubber accelerators in, for example, protective gloves, which are widely used by healthcare professionals. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Rubber accelerators are used in the vulcanization of rubber. However, rubber accelerators for example tetraethylthiuram disulfide (TETD) and zinc diethyldithiocarbamate (ZDEC) may cause contact allergy. Concomitant reactions between ZDEC and TETD have been observed in patients which could be explained by co‐ or cross‐reactivity.To investigate cross‐reactivity between TETD and ZDEC and vice versa.Groups of mice were sensitized with TETD or ZDEC based on reported EC3‐values. Proliferation of lymphocytes were measured on day 5. To test cross‐reactivity, mice were sensitized and challenged 3 weeks later with TETD or ZDEC. The inflammatory response was measured by changes in ear thickness and the proliferative response in CD4+ and CD8+ T cells in the submandibular and cervical draining lymph nodes.Sensitization of mice with doses of ZDEC 3%, TETD 5.6% or TETD 16.2% induced significant increased ear thickness and proliferation of CD4+ and CD8+ T cells. Challenge with ZDEC or TETD in these groups induced significant increased ear thickness. Challenge with ZDEC in mice sensitized to TETD 5.6% or TETD 16.2% induced significant increased proliferation of CD4+ and CD8+ T cells.We show cross‐reactivity between TETD and ZDEC. Patients sensitized to TETD or ZDEC should avoid exposure to both ZDEC and TETD. [ABSTRACT FROM AUTHOR]