Trends and current spectrum of contact allergy in Central Europe: results of the Information Network of Departments of Dermatology (IVDK) 2007–2018*

Abstract

Summary Background Changing patterns of exposure lead to changes in the spectrum of contact allergy in the general population and in patients patch tested for suspected contact allergy. The main contact allergens (haptens) are assembled in the so‐called ‘baseline series’. Objectives To present the current spectrum of contact allergy to baseline series allergens, and its temporal development over the last 12 years, based on data collected by the 56 active departments of the trinational Information Network of Departments of Dermatology (IVDK). Methods Patch‐test data, along with core demographic and clinical information, subdivided into 4‐year periods for all patients patch tested with the baseline series in the IVDK, were analysed descriptively. Moreover, log‐binomial regression analysis addressed temporal trends of specific contact allergies, adjusted for potentially confounding factors. Results Among the 125 436 patients tested with the German baseline series, the most common allergens were nickel (14·7%), fragrance mix I (8·1%), Myroxylon pereirae resin (7·5%) and cobalt (5·2%), with no conclusive trend. The rise and fall of contact allergy to methylchloroisothiazolinone/methylisothiazolinone (MI), following (self‐) regulation in the European Union, reflected the MI contact allergy epidemic. Propolis showed a marked upward trend with a prevalence of 3·94% during the period 2015–2018. Conclusions Decreases in sensitization prevalence likely reflect reduced exposure, with some lag, as seen with hydroxyisohexyl 3‐cyclohexene carboxaldehyde. If no (sufficient) decrease can be observed despite interventions, such as for nickel and chromium, affected subgroups should be identified and their causative exposures explored. Finally, increases such as that observed with propolis, certainly warrant targeted investigation of the exposures driving sensitization, and possibly intervention. What is already known about this topic? Contact allergy is prevalent in the general population. Surveillance based on clinical data offers timely information on trends concerning certain allergens or subgroups at risk. What does this study add? This analysis provides an update of the current contact allergy prevalence in Central Europe, including time trends. This study describes the demographic and clinical profile of patients tested from 2007 to 2018. This research identifies contact allergens that require (further) preventive efforts. Linked Comment: Schuttelaar. Br J Dermatol 2020; 183:800–801.

Relevance of contact sensitizations in occupational dermatitis patients with special focus on patch testing of workplace materials

“…We included information about pre-existing contact sensitization in our data analysis, which gives a more complete picture, particularly concerning sensitizations to predominantly non-occupational allergens (such as nickel). 16 Assessing Most occupational groups displayed diverse sensitization spectra.…”

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“…Clinical signs such as confetti-like depigmentation, poorly defined borders and Koebner phenomenon have previously been suggested to predict disease activity. 1 Measuring the cessation of spread of vitiligo is also of great importance to patients and clinicians and should therefore be reported in future trials if relevant. 2 In this issue of the BJD, van Geel et al report on a novel tool, the Vitiligo Signs of Activity Score (VSAS).…”