Renal artery stenosis in kidney transplants: assessment of the risk factors

BACKGROUND Transplant renal artery stenosis (TRAS) is an important cause of hypertension and renal allograft dysfunction occurring in kidney transplant recipients. However, conflicting predisposing risk factors for TRAS have been reported in the literature. OBJECTIVE The aim of the present study was to assess the potential correlation between possible risk factors and TRAS in a group of living donor renal transplant recipients 1 year after the renal transplantation. METHODS We evaluated the presence of renal artery stenosis in 16 recipients who presented with refractory hypertension and/or allograft dysfunction 1 year after renal transplantation. Screening for TRAS was made by magnetic resonance angiography and diagnosis was confirmed by conventional renal angiography. Age, gender, history of acute rejection, plasma lipid profile, serum creatinine, blood urea nitrogen, serum uric acid, calcium phosphate (CaPO₄) product, alkaline phosphatase, fasting blood sugar, hemoglobin, and albumin were compared between the TRAS and non-TRAS groups. RESULTS Of 16 kidney transplant recipients, TRAS was diagnosed in three patients (two men and one woman). High levels of calcium, phosphorous, CaPO₄ product, and low-density lipoprotein (LDL) cholesterol were significantly correlated with the risk of TRAS 1 year after renal transplantation (P < 0.05). Serum level of uric acid tended to have a significant correlation (P = 0.051). CONCLUSION Correlation between high CaPO₄ product, LDL cholesterol, and perhaps uric acid and TRAS in living donor renal transplant recipients 1 year after renal transplantation might suggest the importance of early detection and tight control of these potential risk factors.