Risk Factors for Invasive Surgical Site Infections Among Adult Single Liver Transplant Recipients at Duke University Hospital in the Period 2015-2020

Background: Invasive primary surgical site infections (IP-SSI) are a severe complication of liver transplant surgery. Identification of risk factors for IP-SSI is critical to IP-SSI prevention.

Methods: All adult single liver transplants performed at Duke University Hospital in the period 2015-2020 were reviewed for IP-SSI occurring within 90 d of transplant. Risks for IP-SSI were identified using least absolute shrinkage and selection operator variable selection procedure. A 2-sided P value of <0.05 was considered statistically significant.

Results: IP-SSI were identified in 34/470 (7.2%) adult single liver transplants. Repeat transplantation, spilt liver, Roux-en-Y biliary anastomosis, anastomotic leak, and post-transplant renal replacement therapy were positively associated with IP-SSI. IP-SSI were associated with increased length of index transplant hospitalization (24.5 versus 10.0 d, P < 0.01) and 1-y all-cause mortality (14.7% versus 4.1%, P = 0.02). Gram positive bacteria were the main pathogens (51.7%), followed by Gram negative bacteria (24.1%) and Candida (24.1%). Multidrug resistance bacteria increased over time (27.3% in 2015 versus 66.7% in 2020, P = 0.17).

Conclusions: In the setting of routine antimicrobial prophylaxis and an overall low rate of IP-SSI, surgical factors were the main determinants of IP-SSI among adult liver transplant recipients. IP-SSI had a negative impact on the length of index transplant hospitalization and 1-y mortality. While the surgical factors associated with an increased risk of IP-SSI are not easily modifiable, their impact may be best contained by close clinical monitoring and tailored antimicrobial therapy.