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Contact Hypersensitivity as a Murine Model of Allergic Contact Dermatitis
Published on: September 26, 2022
Allergic contact granuloma due to palladium following ear piercing
An Goossens1, Ann De Swerdt, Karen De Coninck
1Department of Dermatology, University Hospital, K.U. Leuven, Belgium. an.goossens@uz.kuleuven.ac.be
Abstract:
Two cases of sarcoidal-type allergic contact granuloma due to metals in ear piercing are presented, the first to palladium (Pd) only, and the second to Pd and possibly also to other metals. Both the patients developed papulonodular lesions at the helices following ear piercing, which after 3-4 weeks, became more granulomatous and very resistant to treatment. Indeed, repeated intralesional injections with corticosteroids produced only a temporary regression of the lesions. Biopsies from the persistent granulomatous lesions from the helices in both the patients and the positive test to Pd in case 2, 3 weeks after the patch-testing procedure, demonstrated epithelioid granulomas, with some multinucleate histiocytes surrounded by a lymphocytic-histiocytic infiltrate. Areas of fibrinoid necrosis were found in both the helix biopsies. An infectious pathology was excluded. Patch testing showed a strong positive reaction to Pd only in case 1 and to Pd and nickel in case 2. Chemical analysis of the earring of patient 1 confirmed the presence of Pd; however, analysis of the earrings of the second patient did not show the presence of Pd, but showed the presence of nickel and copper. Both the clinical and histological findings concur with some rarely reported similar observations in the literature.
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