Background: This is a single institution report of the incidence of combined acute antibody-mediated rejection (ABMR) + acute cellular rejection (ACR) [mixed rejection] in HIV (+) kidney transplant recipients.
Methods: We prospectively enrolled 92 HIV (+) patients who received a kidney transplant between 2001 and 2009. There were three cohorts: no rejection [n=26], ACR [n=53], and mixed rejections (ABMR and ACR) [n=13]. Immunosuppression comprised of basiliximab, cyclosporine, sirolimus, and steroid minimization. Fisher exact tests for categorical variables, t test for continuous variables, and Kaplan-Meier estimates were used to describe events.
Results: Mixed rejections were seen in all 13 HIV (+) kidney transplant recipients (14%) with a median time to ABMR of 48 days. Acute cellular rejection occurred in 28% at 1 month and 55% at 12 months. eGFR was lower for recipients who experienced ABMR versus those experiencing ACR and those never experiencing rejection up to 3 years (14 ± 9.4 vs 19 ± 3.3 vs 29 ± 7.3 mL/min, respectively). Kaplan-Meier showed that graft survival up to 9 years was worse in recipients experiencing mixed rejection. Suboptimal donors with terminal creatinine greater than 2.5 mg/dL was associated with increased incidence of mixed rejections versus cellular rejections and no rejection (42% vs 17% vs. 8%, respectively).
Conclusions: Our single center study showed a relatively higher incidence of mixed rejection compared with that reported for non-HIV transplant recipients. A donor terminal serum creatinine greater than 2.5 mg/dL predicted mixed rejection, which was associated with poor outcomes. Donor selection and optimization of immunosuppression may be critical in these patients.