Antonio Vilches

Conversion to Sirolimus Allows Preservation of Renal Function in Kidney and Kidney–Pancreas Allograft Recipients

The major causes of graft failure are chronic allograft nephropathy (CAN) and patient mortality. Sirolimus (SRL) is a powerful immunosuppressant with a less nephrotoxic profile as well as a lower incidence of cancer. The aim of this study was to evaluate the impact of conversion to SRL from calcineurin inhibitor (CNI)-based therapy in kidney (KT) and kidney-pancreas (SPK) allograft recipients. We analyzed renal function, allograft and patient survival, and SRL-associated adverse effects in 93 adult patients (86 KT and 7 SPK), who were converted to SRL between January 2001 and November 2008. The main reason for conversion was CAN (76; 9%) and 52 (7%) were receiving tacrolimus. Conversion occurred at a median 26.2 months. There was a significant improvement in creatinine clearance (CCr) at 6 months after conversion (CCr(baseline) 51.4 vs CCr(6m) 60.4 mL/min; P < .0001), without changes at 12 and 24 months. However, proteinuria increased significantly at 6 months compared with the baseline: 150 mg/24 hours (0-453) versus 0 mg/24 hours (range, 0-309), respectively (P < .0001), but did not progress at 12 or 24 months. At the same time we observed more extensive use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers: 60/5%; 65/3% and 70/2% at 6, 12, and 24 months. There were no changes in blood pressure control. Cholesterol significantly increased at 6 months (218.2 +/- 37 vs. 186.6 +/- 44 mg/dL; P < .0001). Graft and patient survivals at 4 years were 88% and 95%, respectively. Our experience suggested that conversion to SRL constituted a safe alternative with excellent results in patient and graft survival.

Nonprogrammed Vascular Access Is Associated With Greater Mortality in Patients Who Return to Hemodialysis With a Failing Renal Graft

Background In incident hemodialysis (HD) patients, the use of catheters is associated with a worse prognosis when compared with those with an arteriovenous fistula, but the role of vascular access (VA) type in the morbidity and mortality of patients returning to HD with a failing renal allograft is unknown. We aimed to determine the associations between the type of VA and mortality in this population. Methods This was a retrospective observational cohort study of 138 patients who initiated dialysis after kidney transplant failure between 1995 and 2014. We recorded access type, laboratory values at entry, stratified patients per risk, and determined the effect on mortality of programmed VA (PVA), (arteriovenous fistula or PTFE graft) and nonprogrammed VA (UPVA) (tunneled or nontunneled catheters) at the initiation of HD. Results Eighty-five (61.6%) and 53 (38.4%) patients initiated therapy with PVA and UPVA, respectively. Overall mortality was 14.6% at 1 year. Patients using catheters had greater mortality than those with a PVA (log rank P <0.0001). At 24 months, 7 patients died in PVA group versus 22 in UPVA group. Multivariate Cox analysis showed that initiation of HD with a catheter (hazard ratio, 5.90; 95%, confidence interval, 2.83-12.31) was independently associated with greater mortality after adjusting for confounders. Conclusions Nonprogrammed VA with a catheter predicted all-cause mortality among patients with transplant failure reentering HD.