Case series of metal allergy following Nuss procedure: Not only for stainless steel bars

Background Pectus excavatum is often managed with the Nuss procedure. Metal allergies to pectus bars occur in 5% of patients, though pre-operative testing is not generally routine. Objectives This study describes our experience with pre-operative metal allergy testing and post-operative allergic reactions to pectus bars. Methods A retrospective study of patients who underwent a Nuss procedure at our institution from 2010–2020 was performed. Patients with documented “metal” allergy, defined by the need for and positive response to steroid treatment and the absence of infection, were included. Data on patient characteristics and clinical course were analyzed. Results Five of 204 patients (2.5%) identified developed allergic metal reactions. Three of five patients developed allergic reactions to titanium bars, with two requiring early removal of the bar (< 2–3 years). Four patients required more than one course of steroids, and three required debridements for skin breakdown. All patients have maintained good surgical correction at one- and three-years post removal. Conclusions Pectus bar metal allergies occur with both stainless steel and titanium bars. Properly selected patients for pre-operative FinnⓇ Chamber testing may reduce the overall incidence of stainless-steel allergies but may miss titanium bar allergies. Early recognition and treatment of bar allergies may salvage the bar and avoid premature removal.