Contact Dermatitis • Original Article COD Contact Dermatitis Allergic complications from orthopaedic joint implants: the role of delayed hypersensitivity to benzoyl peroxide in bone cement

doi:10.1111/j.1600-0536.2011.01996.x Summary Background. Orthopaedic implants and osteosynthesis materials are increasingly being used. Complications include mainly physical–mechanical problems and infections. Uncommonly, an allergic reaction towards an alloy metal or a bone cement component has been implicated. Potential bone cement allergens include acrylates, benzoyl peroxide, N,N-dimethyl-p-toluidine, and gentamicin. Typical symptoms are pain, swelling, inflammatory skin reactions, implant loosening, and fistula formation. Objectives. To report on 5 patients with complications from a knee or a shoulder joint implant in whom a relevant sensitization to benzoyl peroxide was shown. Methods. Patch tests were performed with the European baseline series, an extended metal series, and a bone cement series. Patch tests with benzoyl peroxide were performed twice in all patients. A bone cement-free replacement was chosen in sensitized patients. Results. In 4 patients sensitized to benzoyl peroxide, a bone cement-free replacement resulted in a considerable decrease or disappearance of pain and swelling, and complete clearing of cutaneous symptoms