BACKGROUND About 50% of kidney-transplant patients undergo organ rejection within 10 years. Chronic allograft nephropathy (CAN) represents the dominant cause of kidney transplant failure and accounts for 50-80% of graft loss in long-term surviving patients. CAN pathogenesis is multifactorial and not-completely elucidated; several reports indicate TGF-beta1 and platelet-derived growth factor (PDGF)-BB expression in CAN suggesting a possible role of these factors in the allograft arteriosclerosis and graft failure. METHODS We investigated the plasma expression concentrations of human growth factors with enzyme-linked immunosorbent assays and appropriate statistical analysis. RESULTS We present evidences showing statistically significant association of CAN with a specific balance between TGF Beat1 and PDGF-BB plasma concentrations, in 129 kidney-transplant patients and 15 healthy controls. Odds ratios were computed to correlate expression-levels with CAN occurrence. CONCLUSIONS We believe these data may suggest a novel non-invasive method to identify early molecular markers of graft deterioration.