The term chronic allograft nephropathy (CAN) has long been used to describe the non-specific injury to kidney transplants that is the most common cause of late (>1 year post-transplant) allograft dysfunction.
With the 2007 Banff classification system, however, the consensus was to eliminate the term “CAN” from the transplant lingo, as it was felt that it diminishes attempts to determine the underlying cause of the histologic lesions. It replaces the term “CAN” with the histologically descriptive term, “interstitial fibrosis with tubular atrophy”, or “IFTA”.
One can even attempt to classify the IFTA into different subgroups according to the mechanism of injury (e.g. IFTA with calcineurin inhibitor toxicity; IFTA with chronic rejection, etc) though it is controversial whether one can really distinguish the mechanism of injury by the histologic pattern on biopsy. In addition, IFTA can also be classified based on the degree of interstitial fibrosis: Grade I (mild, affecting 6-25% of the cortical area), Grade II (moderate, affecting 25-50% of the cortical area), or Grade III (severe, affecting >50% of the cortical area).