Abstract
Background and Aims
Angiotensin II type 1 receptor antibodies (AT1R-Ab) are associated with graft rejection and poor graft outcomes in kidney transplantation (KT). It has been shown that AT1R-Ab have a negative impact on both short-term and long-term graft function, even in the absence of rejection, but this has not been confirmed by other studies. Our aim was to assess the frequency of pretransplant AT1R-Ab and to determine their influence on graft function and survival at 1 year after KT.
Method
We performed a prospective, observational cohort study in 67 adult KT recipients, transplanted between October 2018 and October 2019. Clinical, biological and immunological data of the recipients, age, gender and type of donor, transplant and immunosuppression parameters were collected at the moment of transplantation. A cut-off > 10 U/mL was used for AT1R-Ab detection.
Results
Among the 67 recipients mean age was 41.3 ± 10.3 years, male gender was predominant (59.7%) and the main known cause of end-stage renal disease was glomerular disease. Six patients out of 67 (9%) had a previous kidney transplant. The donor mean age was 50 ± 15.5 years and 65.7% of patients received the kidney graft from a cadaveric donor. Pretransplant AT1R-Ab were detected in 7 out of 67 patients (10.4%) and none of the patients had specific antibodies against human leucocyte antigen. After 1 year of follow-up, median estimated glomerular filtration rate (eGFR) of the recipients was 54 ml/min/1.73 m2 (40.6 – 65.9), 10.4% of patients developed delayed graft function, 7.5% had graft failure and no cases of biopsy proven graft rejection or death was reported. Patients with pretransplant AT1R-Ab had a significant reduced graft function at 1 year after KT compared to those without antibodies [35 (29.8- 55.2) vs 56.1 (41.3 – 66.5) ml/min, p=0.02]. After multivariate linear regression analysis, pretransplant AT1R-Ab were an independent determinant of eGFR at 1 year after KT (β: -14.066; 95% CI: -27.44 - -0.68; p=0.04). Cox regression analysis was used to assess the association of AT1R-Ab along with other clinical, biological and immunological parameters with graft failure. Neither the univariate (HR= 2.07, 95% CI: 0.23-18.52, p=0.51) nor the multivariate (HR= 1.36, 95% CI: 0.10-14.09, p=0.80) Cox regression models showed that pretransplant AT1R-Ab were an independent predictor for graft loss.
Conclusion
We showed that pretransplant AT1R-Ab are an independent determinant of graft function but do not influence the graft survival at 1 year after transplantation in a prospective low immunological risk cohort of kidney transplant recipients.
Pre-Transplant Angiotensin II Type 1 Receptor Antibodies and Anti-Endothelial Cell Antibodies Predict Graft Function and Allograft Rejection in a Low-Risk Kidney Transplantation Setting
