Attitude to nephrolithiasis in the potential living kidney donor: a survey of the German kidney transplant centers and review of the literature.

Living donor kidney transplantation (LD-KTX) is increasing worldwide. With the prevalence of urolithiasis ranging between 4% and 15%, the number of donors with current nephrolithiasis or a history of the disease will increase as well. A questionnaire was sent to all German centers with LD-KTX programs (urologists and general surgeons). Answers were compared for differences between urological and surgical kidney transplant centers. Response rate was 74%. Nephrolithiasis at the time of KTX is an exclusion criterion at 36% of the German centers (58% urological/19% surgical, chi(2) = 4.65, p = 0.03, Fishers exact p = 0.05), 96% of the centers accept kidney donors with a history of nephrolithiasis. The length of the stone-free episode is regarded as relevant by 42% of all centers (58% urological vs. 32% surgical centers, p = ns). Stone composition is a criterion for 54% of centers (66% vs. 44%, p = ns). More than half of the centers accept a history of cystine stones, almost all centers of struvite and urate stones. Donors with current nephrolithiasis were less commonly accepted by urologists than by general surgeons. For almost all centers history of nephrolithiasis does not preclude living kidney donation. Stone composition proved to be of little relevance for decision making.

The impact of FTY720 (fingolimod) on vasodilatory function and arterial elasticity in renal transplant patients.

BACKGROUND: FTY720 has recently demonstrated a similar efficacy in prevention of acute graft rejection compared with mycophenolate mofetil (MMF) in a large phase III trial of de novo renal transplant recipients. Creatinine clearance, however, was significantly lower in FTY720-treated patients. In the present study, we examined the impact of FTY720 on vascular function in a subgroup of patients of this trial. METHODS: Eighteen patients (12 FTY720, 6 MMF) agreed to be enrolled for an analysis of vascular function. Vascular measurements were performed 1.5 years post-transplant and were repeated 3 months after conversion of the patients from FTY720 to MMF. Arterial stiffness was assessed as augmentation index (AI(75)); endothelium-dependent and -independent vasodilation were measured sonographically as flow-mediated dilation (FMD) and as vasodilation after application of glyceroltrinitrate (GTN). RESULTS: Conversion from 2.5 mg FTY720 to MMF led to a significant improvement of FMD (5.40 +/- 1.84 vs 7.77 +/- 3.36%, P 0.02). AI(75) and GTN tended to be higher after conversion without reaching significance (83 +/- 20.43 vs 78.69 +/- 15.39%, P 0.06; 13.76 +/- 4.52 vs 17.39 +/- 3.76%, P 0.07). In the MMF group, AI(75), FMD and GTN did not significantly change during the observation period. CONCLUSION: The present study constitutes the first analysis of the impact of FTY720 on vascular function in humans and reveals an improvement of arterial vasodilatory function after discontinuation of FTY720 in de novo renal transplant recipients on cyclosporine.

A simple, safe and effective citrate anticoagulation protocol for the genius dialysis system in acute renal failure.

BACKGROUND: The Genius dialysis system is a close loop dialysis batch system increasingly used as an intermittent hemodialysis device in intensive care units. The aim of this study was to test the safety and feasibility of a regional citrate anticoagulation protocol with respect to acid-base and electrolyte disarrangements in critically ill patients with acute renal failure. A standard heparin anticoagulation protocol served as control. METHODS AND RESULTS: In a cross-over study design, 27 acute renal failure patients were allocated to a citrate- and heparin-anticoagulated dialysis sessions (4-6 h). For citrate anticoagulation, a 4% sodium-citrate solution was infused into the arterial line of the extracorporeal circuit. A low calcium dialysate (1 mmol/l) was used for all dialysis sessions. Citrate dosing was adjusted according to the post-filter ionized calcium concentration (targeted values 0.5-0.7 mmol/l). There was no routine calcium substitution. Heparin anticoagulation was started with a heparin-loading dose followed by an individual, patient-adjusted continuous heparin infusion. Electrolyte disarrangements, namely hypernatremia, hypo- and hypercalcemia did not occur in either group. Although the highest bicarbonate levels were achieved during citrate anticoagulation (p = 0.021 versus heparin) the acid base values remained equilibrated in both groups. Filter longevity was excellent and the targeted dialysis time was achieved in all but 1 patient. Citrate anticoagulation was well tolerated with respect to cardiovascular hemodynamics. CONCLUSIONS: Citrate anticoagulation can be safely and effectively performed during intermittent Genius dialysis. Calcium supplementation is not routinely required.