Allergic contact dermatitis caused by synthetic rubber gloves in healthcare workers: Sensitization to 1,3‐diphenylguanidine is common

BACKGROUND: The frequency of allergic contact dermatitis has significantly increased in healthcare workers since the transition from latex to synthetic rubber gloves, with 1,3-diphenylguanidine being identified as the most frequently implicated allergen. OBJECTIVES: To highlight the role of 1,3-diphenylguanidine as the culprit allergen in contact allergies to synthetic rubber gloves, to propose recommendations for patch testing, and to discuss alternatives for sensitized subjects. MATERIALS AND METHODS: Patch test data from healthcare workers who developed hand dermatitis after wearing rubber gloves and who reacted positively to glove samples and rubber additives were collected from September 2010 to December 2017 in a Belgian hospital. RESULTS: A total of 44 caregivers were included in this study. Patch tests showed that: (a) 84% of the study population reacted positively to carba mix; (b) 86% reacted positively to 1,3-diphenylguanidine; and (c) 13 (30%) reacted positively to thiuram mix. Half of the subjects reacted positively to gloves containing 1,3-diphenylguanidine, whereas none reacted to accelerator-free gloves. CONCLUSION: The most commonly identified allergen was 1,3-diphenylguanidine, far ahead of thiurams, which were previously described as the most sensitizing accelerators. The use of 1,3-diphenylguanidine-free gloves is recommended. No subject reacted to gloves without accelerators, thus confirming their efficiency among accelerator-sensitized patients. We recommend that 1,3-diphenylguanidine be added to the European baseline series