The histology of solitary renal allografts at 1 and 5 years after transplantation

Immunosuppression: does one regimen fit all?

There has been considerable interest in the individualization of immunosuppressive regimens in an attempt to avoid side effects and improve long-term outcomes. Most available studies have addressed steroid and calcineurin inhibitor minimization in an attempt to prevent the development of chronic allograft dysfunction and cardiovascular mortality. Herein, we evaluate the available evidence for incorporation of these novel strategies in standard clinical care of kidney transplant recipients. Protocol biopsies, pharmacogenetics, and other assays have been developed to guide tailoring of immunosuppression; however, although promising results have been obtained, trials showing their ability to improve long-term outcome are lacking and urgently needed.

Surveillance protocol kidney transplant biopsies: their evolving role in clinical practice

Protocol renal allograft biopsies at fixed time points from transplantation have aided research and provided insights into the pathogenesis of early and late allograft injury. Their role is evolving from research to a clinical management tool needed to detect subclinical pathology requiring treatment adjustment. They frequently reveal unexpected findings and influence therapy in the majority of patients. Detection of subclinical rejection (SCR) remains important despite declining prevalence with triple therapy, the evidence favors treatment, if found. Surveillance biopsies in steroid avoidance and calcineurin inhibitor (CNI) withdrawal programs provide an important safety net against the increased rates of late acute and SCR. Individualization of therapy in high-risk patients and safe reduction of immunosuppression in standard risk individuals becomes possible. Other potentially reversible chronic pathologies that may be detected, include chronic T-cell or antibody-mediated rejection, recurrent disease, BK virus-associated nephropathy, interstitial fibrosis and tubular atrophy and CNI nephrotoxicity, allowing modifications of therapy to limit ongoing graft injury. Biopsy is safe and inexpensive compared with costs of earlier graft failure and return to dialysis. This review summarizes current evidence on use of surveillance histology for the clinical practice of renal transplantation.

Improving long-term renal allograft survival via a road less traveled by

It has become cliché to state that improvements in early renal allograft survival over the past two decades have not led to increased long-term renal allograft survival. However, it is not clear how long-term graft survival can be improved. Here, we present the viewpoint that the road forward does not involve searching for new and more ideal immunosuppressive regimens, but rather detailed patient follow-up to identify specific causes of late renal allograft loss and the development of new therapy designed to address these problems before allograft damage becomes irreversible.

Revisiting the Natural History of IF/TA in Renal Transplantation

Despite the decrease in incidence of early clinical and subclinical rejection and increased 1-year graft survival in renal transplant patients, the rate of graft loss after the first year has been only moderately improved. Protocol biopsies obtained in the first year have shown rapid increase in the prevalence of IF/TA. This finding has been correlated with later allograft dysfunction and loss, mostly in cases of concomitant interstitial inflammation and fibrosis (1). The landmark study by Nankivell et al., performed in recipients of organs from deceased young donors under early cysclosporin-based immunosuppression, suggested two distinct phases of injury involved in IF/TA: an early tubulo-interstitial damage from ischemic injury and allograft rejection and, beyond 1 year, microvascular, glomerular and additional tubulo interstitial injury interpreted as secondary CsA toxicity (2). Since this publication, chronic antibody-mediated rejection has been better identified as leading causes of late graft dysfunction. Moreover, a recent study showed that most cases of kidney graft loss have an identifiable cause that is not idiopathic IF/TA or CNI toxicity and that alloimmunity remains the most common mechanism leading to failure (3). Thus, with the current immunosuppressive regimens and the input of molecular phenotyping, one may question the natural history of IF/TA.