Patch testing with rubber series inEurope: a critical review and recommendation

Abstract

SummaryBackground. Rubber additives constitute an important group of contact allergens, particularly in certain occupations. Objectives. To collect information regarding the current practice of using a 'rubber series' in Europe, and discuss this against the background of evidence concerning the prevalence of allergy in order to derive a recommendation for a 'European rubber series'. Methods. The following were performed: (i) a survey targeting all members of the COST action 'StanDerm' consortium, (ii) analysis of rubber contact allergy data in the database of the European Surveillance System on Contact Allergies, and (iii) a literature review. Results. Information from 13 countries was available, from one or several departments of dermatology, and occasionally occupational health. Apart from some substances tested only in single departments, a broad overlap regarding important allergens was evident, but considerable variation existed between departments.Conclusions. An up-to-date 'European rubber series' is recommended, with the exclusion of substances only of historical concern. A 'supplementary rubber series' containing allergens of less proven importance, requiring further analysis, is recommended for departments specializing in occupational contact allergy. These should be continually updated as new evidence emerges.

Patch test results with the European baseline series and additions thereof in the ESSCA network, 2015‐2018

“…Compared with thiuram mix, sensitization to the other rubber allergens, including N ‐isopropyl‐ N′ ‐phenyl‐ p ‐phenylenediamine, is relatively rare. Of note, thiurams, including the mix, are considered to detect contact allergy to dithiocarbamates, as corresponding thiurams and dithiocarbamates constitute redox pairs 44 . Positive patch test reactions to the benzothiazoles are almost twice as common in the youngest, compared with the oldest age group, likely pointing to occupational exposure and sensitization, for example, in the healthcare sector, or perhaps to fashion‐related exposures.…”

“…Positive patch test reactions to the benzothiazoles are almost twice as common in the youngest, compared with the oldest age group, likely pointing to occupational exposure and sensitization, for example, in the healthcare sector, or perhaps to fashion‐related exposures. In general, if (occupational) exposure to rubber additives is suspected to cause allergic contact dermatitis, testing with a dedicated rubber series, pieces of rubber products, or ultrasonic extracts thereof is indicated 44 . Patch testing with rubber constituents has been discussed in‐depth elsewhere, 25,44 particularly the problem of irritant patch test reactions to 1,3‐diphenylguanidine, 45 which has been found, at the same time, to be an important allergen in synthetic rubber gloves 46 …”

European Surveillance System on Contact Allergies (ESSCA): results with the European baseline series, 2013/14

“…It has to be noted that diagnostic work‐up of patients with suspected rubber‐related allergic contact dermatitis should not solely rely on these four EBS allergens, because as many as 40% with eventually diagnosed contact allergy to rubber additives will be missed if further rubber additives and mix breakdowns are not additionally tested . An in‐depth discussion of adequate patch test diagnosis of rubber contact allergy is found in a recent review . The prevalence of contact allergy to p ‐ tert butylphenol formaldehyde resin in consecutive patients halved, compared to 2004, which may be indicative of a reduced importance of this adhesive mainly used in footwear; however, reliable exposure information is, as in many fields, lacking.…”

“…7 An in-depth discussion of adequate patch test diagnosis of rubber contact allergy is found in a recent review. 43 The prevalence of contact allergy to p-tert butylphenol formaldehyde resin in consecutive patients halved, compared to 2004, which may be indicative of a reduced importance of this adhesive mainly used in footwear; however, reliable exposure information is, as in many fields, lacking.…”

A proposal to create an extension to the European baseline series

“…and 1,3‐diphenylguanidine to avoid false‐negative reactions. However, given the low yield from testing with 1,3‐diphenylguanidine alone (Table ), it may be better to restrict this to a rubber series and patients with hand dermatitis.…”