Chronic renal transplant rejection is a major cause of late transplant failure. About 50% of graft losses after the first year are due to patient death with a functioning transplant. In the survivors, about 50% to 80% of grafts are lost due to chronic rejection [1]. The design of studies to decrease the incidence of chronic rejection is hampered by the very large number of patients and the long-term follow up required [2]. The identification of early surrogate biomarkers for chronic rejection is therefore of considerable interest.

Keywords: subclinical rejection, protocol biopsies, urine spectroskopy