Cardiovascular diseases are the main causes of morbidity and mortality following renal transplantation. Atherosclerotic structural changes, which can be detected by high-resolution B-mode ultrasonography, begin before clinical findings. However, little is known about the extent of these abnormalities in children after renal transplantation. We aimed to determine early structural changes of large arteries in renal transplant recipients without cardiovascular disease and to evaluate the role of clinical and laboratory features on IMT of carotid arteries. IMT and hemoglobin, serum levels of creatinine, acute phase proteins, lipid profile, and homocysteine were examined in 24 asymptomatic renal transplant recipients (median age 16.5 yr; range 8-25), and 20 healthy controls (median age 16 yr; range 9-24). CCA and ICA were evaluated in patients and controls with a high-resolution B-mode ultrasonography in multiple projections to optimize detection of carotid IMT. Measurement of IMT of both CCA [0.36 mm (range 0.16-0.48) vs. 0.28 mm (range 0.21-0.35), p < 0.001] and ICA [0.27 mm (range 0.16-0.48) vs. 0.22 mm (range 0.1-0.26), p < 0.001] were significantly higher in renal recipients than in healthy controls. Among several parameters assessed, only significant correlations were found between duration of CRF, duration of dialysis prior to transplantation and ICA-IMT (p = 0.06 and p = 0.02, respectively) and between mean past serum calcium-phosphorus ion product and CCA-IMT (p = 0.002). In conclusion, our observations indicate that vascular changes begin early in the course of CRF and are directly related to time on CRF and dialysis. These changes can be detected by measuring CCA/ICA-IMT ultrasonographically. We suggest that early renal transplantation can potentially avoid long-term cardiovascular events in children with end stage kidney disease.