WITHDRAWN: Incidence and outcome of surgical site infections in thoracic-organ transplant recipients registered in the Swiss Transplant Cohort Study

Abstract

<h2>Abstract</h2><h3>Background</h3> Transplant-related surgical site infections (SSI) pose a relevant threat for heart (HTx) and lung transplant recipients (LuTx). Considering the paucity of data, we analyzed HTx and LuTx within the Swiss Transplant Cohort Study (STCS). <h3>Methods</h3> The STCS dataset was used to identify adult HTx and LuTx with a follow-up of at least 90 days post-transplant between 2008 and 2020. Risk factors for SSIs were investigated with logistic regression. Cox proportional hazard models, one model starting from transplantation with 365 days follow-up and one model starting 90 days post-transplant with unrestricted follow-up, were applied to address the impact of SSIs on patient and graft survival. <h3>Results</h3> Of 356 HTx 31 (8.7%) and of 450 LuTx 21 (4.7%) individuals experienced SSIs. In both HTx and LuTx, the majority of SSIs were caused by bacteria, most frequently coagulase-negative staphylococci and <i>Enterococcus</i> spp.. In HTx, diabetes mellitus (multivariable OR 2.4, 95%CI 1.02-5.8, <i>P</i>=0.04) and maintenance immunosuppression without calcineurin or mTOR inhibitor in the first week post-transplant (multivariable OR 3.9, 95%CI 1.3-11.4, <i>P</i>=0.01) were independent risk factors for SSIs. In multivariable Cox proportional hazard models, SSIs were associated with reduced patient and graft survival in LuTx (365-day model: HR 5.0, 95%CI 1.9-13.0; <i>P</i>=0.009; 90-day baseline model: HR 2.2, 95%CI 1.2-4.1, <i>P</i>=0.02), whilst we did not detect an association in HTx. <h3>Conclusions</h3> Gram-positive bacteria predominated in SSIs after both HTx and LuTx. LuTx with SSI had impaired failure-free survival as compared to those without SSI.