A 50-year-old man presented with a chronic pruritic erythemato-desquamative patchy dermatitis with linear fissures involving the upper-ear region bilaterally. He had had this dermatitis for four months.On physical examination no other lesions were found but the patient referred previous similar lesions in the concha of the ear. Previous diagnoses of psoriasis, atopic dermatitis, and acanthoma fissuratum had been made. Patch tests with the Italian baseline series of contact allergens (Societa Italiana di Dermatologia Allergologica Professional e Ambientale-SIDAPA) showed a positive reaction to thiuram mix 1% pet (+ at 48 hours/++ at 72 hours) and mercaptobenzothiazole 1% pet (+ at 48 hours /++ at 72 hours). Further questioning found the patient wore spectacles and used a mobile phone headset for 3-4 hours per day. Analysing the objects, it was found that the eyeglass chain had a black rubber ring (figure 1A) which touched the area of the upper ear, while the headset had a black rubber ring around the speaker and a black rubber cone around the wire, both of which were in strict contact with the site of dermatitis (figure IB). The diagnosis of allergic contact dermatitis to rubber components of the spectacles chain and the headset was made. The patient refused further investigations; the dermatitis healed after avoiding contact with the offending items.
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