Current patch test results with the European baseline series and extensions to it from the 'European Surveillance System on Contact Allergy' network, 2007-2008

BACKGROUND: The pattern of contact sensitization to the supposedly most important allergens assembled in the baseline series differs between countries, presumably at least partly because of exposure differences. Objectives. To describe the prevalence of contact sensitization to allergens tested in consecutive patients in the years 2007 and 2008, and to discuss possible differences. METHODS: Data from the 39 departments in 11 European countries comprising the European Surveillance System on Contact Allergy network (www.essca-dc.org) in this period have been pooled and analysed according to common standards. RESULTS: Patch test results with the European baseline series, and country-specific or department-specific additions to it, obtained in 25 181 patients, showed marked international variation. Metals and fragrances are still the most frequent allergens across Europe. Some allergens tested nationally may be useful future additions to the European baseline series, for example methylisothiazolinone, whereas a few long-term components of the European baseline series, namely primin and clioquinol, no longer warrant routine testing. CONCLUSIONS: The present analysis points to 'excess' prevalences of specific contact sensitization in some countries, although interpretation must be cautious if only few, and possibly specialized, centres are representing one country. A comparison as presented may help to target in-depth research into possible causes of 'excess' exposure, and/or consideration of methodological issues, including modifications to the baseline series

The European standard series in 9 European countries, 2002/2003 -- first results of the European Surveillance System on Contact Allergies

Since January 2001, the European Surveillance System on Contact Allergies (ESSCA), supported by European Union funding (contract QLK4-CT-2001-00343), has started to collect patch-test data. This comprises a standardized clinical history and the patch-test results using the European standard series, from 17 centres in 9 European countries listed above. In 2002 and 2003, 10 511 patients\u2019 test results have been pooled and analysed. The anamnestic data partly reflect the subspecialties of some centres. The most common allergen was nickel sulfate (17.3%); however, large international variations were observed. The prevalence of contact allergy to Myroxylon pereirae resin (balsam of Peru) (5.8%) is coming close to the frequency found with the fragrance mix (6.4%). Regarding contact allergy to chromium compounds, different frequencies were noted in the 2 centres focused on occupational dermatitis (2.3% in the FIOH versus 7.4% in the Nofer Institute). These most likely reflect the beneficial effect of addition of ferrous sulfate in one, but not the other country. As differences may partly be due to different patch-test reading, standardization may need to be refined further. By providing post-marketing surveillance in the field of contact allergy, ESSCA will meet its objective of increased consumer safety across Europe. Key words: clinical epidemiology; comparative study; contact allergy

The European vaseline series in 10 European Countries, 2005/2006 – Results of the European Surveillance System on contact Allergies (ESSCA). Contct Dermatitis 61:31-38, 2009

BACKGROUND: Continual surveillance based on patch test results has proved useful for the identification of contact allergy. OBJECTIVES: To provide a current view on the spectrum of contact allergy to important sensitizers across Europe. PATIENTS/METHODS: Clinical and patch test data of 19 793 patients patch tested in 2005/2006 in the 31 participating departments from 10 European countries (the European Surveillance System on Contact Allergies' (ESSCA) www.essca-dc.org) were descriptively analysed, aggregated to four European regions. RESULTS: Nickel sulfate remains the most common allergen with standardized prevalences ranging from 19.7% (central Europe) to 24.4% (southern Europe). While a number of allergens shows limited variation across the four regions, such as Myroxylon pereirae (5.3-6.8%), cobalt chloride (6.2-8.8%) or thiuram mix (1.7-2.4%), the differences observed with other allergens may hint on underlying differences in exposures, for example: dichromate 2.4% in the UK (west) versus 4.5-5.9% in the remaining EU regions, methylchloroisothiazolinone/methylisothiazolinone 4.1% in the South versus 2.1-2.7% in the remaining regions. CONCLUSIONS: Notwithstanding residual methodological variation (affecting at least some 'difficult' allergens) tackled by ongoing efforts for standardization, a comparative analysis as presented provides (i) a broad overview on contact allergy frequencies and (ii) interesting starting points for further, in-depth investigation