Pretransplant and protocol biopsies may help in defining short and mid-term kidney transplant outcome

Although many variables may affect long-term graft survival no biomarker is available to identify donor kidney with poor quality and with inadequate short and long-term outcome. While in marginal donors pre-transplant renal biopsies are commonly performed to establish if donor kidneys are suitable for transplantation they are not performed in standard donors. In this study we assessed the relevance of pre-transplant morphological features on post-transplant renal function and evaluated the association between perioperative parameters with posttransplant histological and clinical findings. Kidney transplant recipients undergone pre-transplant and post transplant protocol biopsies at 1, 6, and 12 months were enrolled in the study. Perioperative and posttransplant clinical and biochemical parameters were recorded. Semiquantitative analysis of PAS stained kidney sections was used to determine the degree of lesions. Glomerular volume was measured by computed morphometry. A strong inverse correlation was found between donor age and renal graft function at 1, 6, and 12 months after transplantation. A prompt functional recovery was associated with a better renal function at 6 months and one year. Kidneys with higher glomerular volume demonstrated a lower serum creatinine at 1 month. Higher tubulo-interstitial grading at protocol biopsies was associated with a poor renal function at 1 month. Our findings confirm the importance of donor age in kidney transplant long-term outcome and demonstrate that pretransplant and protocol biopsies are valid options to determine graft outcome and to define therapeutic strategies and tailor immunosuppressive regimen for each patient.