Background: Among hospital-acquired infections, surgical site infections (SSI) are common. The occurrence of SSIs in the early post-transplant course poses a relevant threat for simultaneous pancreas kidney transplant (SPK-Tx) or pancreas transplant (P-Tx) recipients.

Methods: Adult SPK-Tx and P-Tx recipients with a follow-up of at least 90 days were identified in the Swiss Transplant Cohort Study (STCS) dataset. Except the categorization of SSIs according to CDC criteria, all other data were prospectively collected. Risk factors for SSIs were investigated with logistic regression. A Weibull accelerated failure-time model was applied to address the impact of SSIs on length of stay, correcting for transplant-related complications and delayed graft function.

Results: Of 130 transplant recipients, 108 SPK-Tx and 22 P-Tx, 18 (14%) individuals developed SSIs within the first 90 days after transplantation. Deep incisional (7, 38.9%) and organ/space infections (8, 44.4%) predominated. In the majority of SSIs (11, 61.1%; 2 SSIs with simultaneous identification of fungal pathogens) bacteria were detected with Enterococcus spp. being most frequent. The median duration of hospitalization after transplantation was significantly longer in recipients with SSI (median 26d; IQR [19, 44]) than in patients without SSI (median 17d; IQR [12, 25], P = 0.002). In multivariable analysis, SSIs were significantly associated with an increased length of stay and prolonged the duration of hospitalization by 36% [95% CI: 4, 79].

Conclusions: SSIs after SPK-Tx and P-Tx were found at a quite low frequency of 14%. Among pathogens, Enterococcus spp. predominated. SSIs were independently associated with a longer hospitalization after transplantation.