Eosinophilic cellulitis mimicking acute infection after total knee arthroplasty: A case report

Abstract

Background: One of the common complications after total knee arthroplasty (TKA) is periprosthetic joint infection (PJI). The differential diagnosis should include allergies to implant components or cement constituents, for which the clinical manifestation may mimic an infection. An allergic skin reaction to suture material after TKA mimicking acute PJI has to date never been described in the literature. Case report: We present a case of acute allergic skin reaction to polydioxanone suture material (Stratafix™, Ethicon, Johnson & Johnson) initially suspected to be acute PJI one week after TKA. The patient was treated with debridement, extensive synovectomy, irrigation and implant retention followed by antibiotic therapy. The bacteriological analysis was negative and the histological examination of the excised wound showed Wells-type eosinophilic cellulitis. The definitive diagnosis was an allergic reaction to sutures mimicking an acute PJI. Conclusion: An allergic skin reaction to suture material mimicking acute PJI has an extremely low incidence and therefore has been barely described. The different clinical presentations complicate diagnosis and treatment decisions, particularly in acute settings. The formal diagnosis is made by histopathological analysis of wound tissue in the presence of negative microbiological cultures. We may consider wound biopsy during or before surgical revision as an additional tool in PIJ strategy work-up.