Examining the Role for Donor-specific Antibody Testing in Simultaneous Liver-kidney Transplantation: A Single-center Analysis of Outcomes

Background. Simultaneous liver-kidney transplantation (SLKT) is increasingly used for patients with concurrent end-stage liver and renal disease. Emerging evidence suggests that simultaneous liver transplant can provide a tolerogenic benefit to multiorgan transplant recipients. Posttransplant donor-specific antibody (DSA) may be associated with worse outcomes; however, the role for testing DSA in SLKT is unclear. Methods. This study retrospectively assessed the impact of DSA on outcomes following primary SLKT at a large-volume center between 2008 and 2018. Patients were grouped by positive DSA, negative DSA, and DSA not tested, and data were obtained from our institutional database and chart review. Results. The cohort included 138 SLKT recipients with a mean age of 56.1 +/- 9.7 y; 61.6% were male, and 55.8% were Hispanic. Overall, 62 patients were tested for DSA posttransplant, and 33 patients (23.9%) had at least 1 DSA detected. A total of 34 patients (24.6%) experienced at least 1 episode of liver rejection, and 23 patients (16.7%) experienced kidney rejection. Over 50% of patients with de novo DSA changed status during their posttransplant course. Rates of both liver and kidney rejection were slightly higher in the DSA(+) group, but liver allograft, kidney allograft, and patient survival did not differ when grouped by whether DSA testing was performed or DSA positivity. Conclusions. These data demonstrate that SLKT is associated with excellent long-term patient and allograft survival with a relatively low rate of rejection. In our experience, testing for DSA does not impact SLKT outcomes, and further multicenter analyses are needed to establish standard of care. (Transplantation 2023;107: 1115-1123).