Chronic Allograft Nephropathy

Since the first successful kidney transplantation in 1954 between Identical twins, a new modality to treat patients with terminal kidney insufficiency was born. Although the results in the first decades were modest, continuous development has characterized this captivating field. A major advance was the introduction of the new immunosuppressant cyclosporine A in the early 1980s. The fundament of its success was the aptitude to improve kidney graft survival significantly over the first year, and calcineurin inhibitors are the cornerstone of immunosuppression even in the present decade. Chronic allograft nephropathy is a histopathological diagnosis used to denote features of chronic interstitial fibrosis and tubular atrophy within the renal allograft. It remains the most common cause of graft dysfunction and loss after renal transplantation. The term Chronic allograft nephropathy was proposed in 1991, and it replaced the previously used term “chronic rejection”. The intention was to unify chronic histological changes seen under light microscopy, such us interstitial fibrosis, tubular atrophy, transplant glomerulopathy and vasculopathy. The pathophysiology behind each of these features may nevertheless be different. The processes involved are approached by dividing them roughly into immunological and non-immunological factors, although they may be interrelated. In this chapter we will discuss the histological features, the pathogenesis, the different etiologies and the therapeutic possibilities in cases of chronic allograft nephropathy.