Intolerance of osteosynthesis material: evidence of dichromate contact allergy with concomitant oligoclonal T‐cell infiltrate and TH₁‐type cytokine expression in the peri‐implantar tissue

Abstract

Background: We report on a 37‐year‐old man without history of previous allergic disease who developed an aseptic intolerance reaction to a chromium‐cobalt alloy, with local discomfort, loosening, and absence of fracture healing. Both in vivo and in vitro allergoimmunologic diagnostic tests were performed. Methods: Patch testing was done with a European standard series. Specific serum IgE was measured by CAP‐FEIA. In addition to immunohistology (APAAP method), peri‐implantar tissue was further analyzed by PCR to determine T‐cell‐receptor‐γ rearrangement and thus the potential clonal (antigen‐driven) T‐cell repertoire. The actual tissue mRNA expression for IL‐4, IL‐6, and IFN‐γ was visualized by RT‐PCR. Results: Skin testing gave a delayed‐type reaction to dichromate. Specific serum IgE to natural rubber latex and grass pollen was found – but without clinical symptoms. Immunohistology revealed a monocytic and dense T‐cell infiltrate. The latter, instead of being random, showed an oligoclonal T‐cell receptor rearrangement. In addition, there was TH 1 ‐type mediator expression (IL‐6 and IFN‐γ, but not IL‐4). Conclusions: Skin test, examination of peri‐implantar tissue, and the prompt healing after replacement of the osteosynthesis material suggest an allergic reaction. PCR analysis of peri‐implantar tissue can further help to identify and understand allergy‐mediated implant intolerance reactions.