Low-grade albuminuria reduction with angiotensin II type 1 receptor blocker in renal transplant recipients.

BACKGROUND: Microalbuminuria, defined as urine albumin to urine creatinine ratio of 30 to <300 mg/g, is an established risk factor for cardiovascular morbidity and mortality in the general population. Low-grade albuminuria (<30 mg/g) is considered a marker for subclinical vascular damage that predisposes to future cardiovascular diseases and death. Lowering urinary albumin excretion reduces the risk of cardiovascular disease. Our study was designed to evaluate the influence of angiotensin II type 1 receptor blocker (ARB) in normotensive renal transplant recipients with low-grade albuminuria. PATIENTS AND METHODS: Our 6-month prospective observation study used a randomized control and open-label design as we examined the effects of an ARB (valsartan) on blood pressure, urinary albumin excretion, hematocrit, serum potassium and estimated glomerular filtration rate (eGFR) in normotensive recipients with allografts of more than 1 year. A total of 35 renal transplant recipients were enrolled in this study. Patients were randomly assigned to 2 groups: ARB group (n=18), receiving 40-80 mg valsartan daily for 6 months, and the control group (n=17). RESULTS: In the ARB group, urine albumin excretion was significantly reduced from 25.9 ± 19.1 mg/g to 12.0 ± 9.6 mg/g at 6 months after administration. eGFR decreased slightly at 6 months after administration. However, no patients undergoing treatment for adverse effects required discontinuation of ARB. CONCLUSIONS: This study reveals that ARB is safe and reduces low-grade albuminuria in normotensive renal transplant recipients. Thus, early treatment of ARB in recipients with low-grade albuminuria may prevent cardiovascular disease after renal transplantation.

Pharmacokinetic study of interleukin-2 following intravenous injection in hemodialysis patients with renal cell carcinoma.

The purpose of the present study is to determine the change in blood concentration of interleukin-2 (IL-2) after intravenous injection in hemodialysis patients and to assess its safety. Four hemodialysis patients who underwent nephrectomy due to renal cell carcinoma were treated with IL-2 at a dose of 350 000-700 000 JRU by intravenous injection. Pharmacokinetic parameters were analyzed from the serum IL-2 concentration, which reached its peak just after the end of infusion, followed by biphasic elimination, and was below the detection limit in all patients at 24 h postinfusion. In comparison with patients with normal renal function, the volume of distribution in the serum compartment was almost comparable (3820 +/- 2020 mL). Clearance (50.47 +/- 11.50 mL/min) decreased to 40%, and the half-life of the distribution phase (0.45 +/- 0.19 h) and that of the terminal phase (1.72 +/- 0.20 h) were distinctly longer. The area under the blood concentration-time curve was about two-fold higher than that of non-hemodialysis patients. In all patients, there were no serious adverse reactions. The results of the present study suggest that intravenous IL-2 therapy can be safely performed in hemodialysis patients.

Kidney transplants from living related donors having double inferior vena cava.

We performed four living related kidney transplantations from donors with double inferior vena cava (D-IVC), in which the left kidney was selected in two cases and the right in two cases. By dissecting the right internal iliac vein and isolating the right external iliac vein, the surgical procedure of the recipient side was so devised as to avoid any complications. In one patient, the surgical procedure of the donor side was modified to extend the donor left renal vein by anastomosis of part of the donor IVC to the renal vein. In the other case, no special treatment was necessary due to the patient's slender physique. In all four cases, transplants were successfully performed. The following conclusions can be made from these results: If the donor has D-IVC, it is essential to carefully conduct pre-operative examinations including angiography and venography to investigate other possible anomalies and blood flow of the renal vein. In addition, the graft must be carefully selected so that it is not disadvantageous to the donor. If there is no disadvantage to the donor as to which kidney is selected, the kidney with the longer renal vein should be transplanted.

Nephrogenic diabetes insipidus due to hydronephrosis in a patient with a solitary kidney.

A 68-year-old man with a history of nephrectomy of the right kidney was admitted to our hospital with a 1-month history of polyuria (> 41 per day). He also exhibited hyposthenuria, which was unresponsive to treatment with exogenous vasopressin. Radiographic examination revealed partial obstruction of the left ureter and moderate hydronephrosis. The cause of the obstruction was cancer of the ureter. After drainage using a nephrostomy tube, the polyuria and hyposthenuria were gradually resolved. This is the first known case of nephrogenic diabetes insipidus due to hydronephrosis in a patient with a solitary kidney.

Results of cadaver kidney transplantation with right renal vein extension.

INTRODUCTION: Several methods to lengthen the renal vein of the allografts have been proposed in order to secure the surgeon's field of vision and to allow appropriate positioning of the graft. However, its safety and complications have not been clarified. Furthermore, its long- and short-term results have not been investigated. Therefore, we studied the results of this operative procedure to confirm the safety of the technique. METHODS: The right renal vein extension was utilized when the donated right kidney from a cadaver donor had sufficient length of the inferior vena cava wall. The results of 10 patients who received kidney transplantation with renal vein extension were examined. RESULTS: None of the patients had vascular complications. The transplanted kidney functioned in all patients; 3- and 5-year graft survival was 100 and 75.0%, respectively. CONCLUSIONS: The results confirmed that this technique was safe and without complications and did not affect the long- and short- term results of patients who received cadaver kidneys. Therefore, we conclude that it is appropriate to adapt this technique when the physician judges the long renal vein suitable for the procedure.

Cadaveric renal transplantation from a non-heart-beating pediatric donor into adult recipients.

INTRODUCTION: The use of cadaveric pediatric kidneys has been suggested as a means to overcome organ shortage, but is debated because of technical complications and an increased incidence of functional allograft impairment. METHODS: We experienced 2 cases of cadaveric renal transplantation from a non-heart-beating pediatric donor. RESULTS: In our cases, transplanted kidneys achieved good graft function and proteinuria due to glomerulosclerosis was not recognized. CONCLUSION: Previous reports indicate that in transplantation from pediatric donors into adults recipients, glomerular sclerosis occurs as the reason for impairment of grafts. Further, cadaveric renal transplantation from a non-heart-beating donor has a warm ischemia time and an increased risk of hyperfiltrated injury and graft failure. If transplantation of pediatric kidneys into adults from a non-heart-beating donor is performed, BMI and BSA must be carefully considered in the selection of recipients in order to avoid imbalance between nephron supply and metabolic demands and to insure successful, healthy grafts.

Role of renin-angiotensin system and nuclear factor-kappaB in the obstructed kidney of rats with unilateral ureteral obstruction.

The present study was conducted to elucidate the role of oxidative stress and nuclear factor-kappaB (NF-kappaB) in the beneficial effects of angiotensin receptor blockade on obstructive nephropathy. Unilateral ureteral occlusion in rats elicited tubulo-interstitial fibrosis with concomitant macrophage infiltration and increased expression of monocyte chemoattractant protein-1. These changes were accompanied by an induction of renal cortical lipid peroxidation and activation of NF-kappaB. Both an AT(1) antagonist, candesartan, and a NF-kappaB inhibitor, pyrrolidine dithiocarbamate, markedly attenuated these changes and to a similar extent. These results suggest that the beneficial effects of angiotensin blockade are mediated by the inhibition of oxidative stress and subsequent NF-kappaB activation in obstructive nephropathy.

Hepatocyte growth factor ameliorates renal hemodynamic disorder after ischemia/reperfusion.

Ischemic injury of the transplanted kidney is one of the causes of reduced graft survival. The purpose of the present experiment was to examine whether hepatocyte growth factor (HGF) would improve acute renal hemodynamic recovery immediately after cold ischemia. Addition of HGF to the preservation solution during 3 h cold ischemia of dog kidney accelerated both recovery of renal blood flow and glomerular filtration rate (GFR). It is suggested that HGF may be useful for preservation of excised kidney for transplantation. As intrarenal arterial infusion of HGF in normal dog kidney had no effects on renal hemodynamics, mechanisms other than direct vasodilator action of HGF appear to be operating in the protection.