Role of penile vascular insufficiency in erectile dysfunction in renal transplant recipients

The objectives of this study were to define the role and haemodynamic features of penile vascular insufficiency in impotent renal transplant recipients (RTR) as well as to establish the possible vascular risk factors for impotence in these patients. A total of 54 RTR (35 impotent and 19 potent) and 21 potent healthy subjects were included in this study. All patients were assessed clinically and by measurement of serum creatinine, serum bilirubin, cyclosporine blood levels, haemoglobin and total serum cholesterol. All subjects were subjected to intracavernous injection of 20 microg prostaglandin E1 followed by colour Duplex sonographic examination. Our results showed that impotent RTR were significantly more likely than potent RTR to have hypertension, diabetes and hypercholesterolaemia (P<0.05). Arterial occlusive disease was identified in 42.9% of impotent RTR. Findings suggestive of veno-occlusive dysfunction were found in 68.6% and 26.3% of impotent and potent RTR, respectively (P=0.003). Unilateral ligation of the internal iliac artery has a negative role on haemodynamic parameters compared to unilateral end-to-side anastomosis to external iliac artery in impotent RTR (P<0.05). Impotent RTR receiving more than one antihypertensive drug showed significant decrease in basal peak systolic velocity (PSV), dynamic PSV, erectile angle and cavernosal artery diameter compared to those receiving one drug (P<0.05). In conclusion, penile vascular insufficiency appears to play a substantial role in the pathogenesis of impotence in transplant patients. Anastomosis of the graft to external iliac artery could preserve the potency to some degree. Antihypertensives should be reduced as much as possible to avoid their negative effects on erectile function.