First case of occupational purpuric hand allergic contact dermatitis to benzoyl peroxide with airborne face eczema

We present the first case of occupational purpuric hand eczema with airborne face eczema due to benzoyl peroxide (BP) contact allergy in an art object conservator. A 55-year-old caucasian male was referred for persistent hand forearms and face eczema. He presented vesiculous, bullous and purpuric lesions of the fingers and palms of the hands (Figure 1) and edematous eczema of the face and neck (Figure 2) on examination. He had been working as an art object conservator for 2–3 years (and cabinetmaker previously). Patch tests were performed with the European Baseline Series and cosmetic, rubber, perfume plastic/glue, epoxy and acrylates series using test preparations from D'Estaing (Grasse France) or SmartPractice Europe (Greven, Germany), using IQ ultra chambers® from Chemotechnique MB Diagnostics AB (Vellinge, Sweden) and Mepilex® border tape, according to European Society of Contact Dermatitis guidelines with an occlusion time of 48 h. A positive result was found for benzoyl peroxide 1% pet (++) at D3 and D10 with a current definite relevance. He reported using a sealant 'Soloplast' in his workplace with bare hands. A hardener containing benzoyl peroxide was found in this sealant. He was advised to avoid exposure to this product at his workplace. He reported relapses of allergic contact dermatitis (ACD) when handling this sealant. He completely healed after avoidance of exposure to BP. Purpuric ACD is rare and has been reported with rubber coumpounds, textile compounds, plants, epoxy resins and isothiazolinones.1, 2 Purpuric patch test reactions have also been described (textile dyes).3 The purpuric form of ACD to BP is unusual, with only one case reported.4 Airborne patterns of ACD have also been described after exposure to this allergen, for example, to molten candle wax, plaster in an orthopaedic technician and insulation plastics and cables in an electrician.5-7 Purpuric or ecchymotic lesions can mimic a chemical burn or an irritation,1 especially if the hands are affected, and hamper the diagnosis of purpuric ACD. BP can be found in the occupational context, where it is mainly used in the production of plastics. It is known to be a strong irritant and weak allergen. BP is also frequently used in topical drugs for acne, with a few cases of BP-induced ACD reported.8 In conclusion, this is the first case of purpuric hand ACD associated with benzoyl peroxide. This allergen can be found in many industries, and BP-ACD could remain undiagnosed in cases of atypical presentations of hand injuries, such as purpuric presentations, if not known. Marion Menanteau: Writing – original draft; investigation; writing – review and editing. Lynda Bensefa-Colas: Supervision. Marie-Noëlle Crepy: Investigation; writing – review and editing; supervision. The authors declare no conflicts of interest. The patient has given his written consent.