Scott B. Campbell

Everolimus with Optimized Cyclosporine Dosing in Renal Transplant Recipients: 6-Month Safety and Efficacy Results of Two Randomized Studies

Two prospective, randomized studies evaluated everolimus 1.5 vs. 3 mg/day with steroids and low‐exposure cyclosporine (CsA) (C2 monitoring) in de novo renal transplant patients. Everolimus dosing was adjusted to maintain a minimum trough level of 3 ng/mL. Study 1 (A2306; n = 237) had no induction therapy; in Study 2 (A2307; n = 256) basiliximab was administered (Days 0 and 4). The primary endpoint was renal function at 6 months. CsA C2 target levels, initially 1200 ng/mL in Study 1 and 600 ng/mL in Study 2, were tapered over time post‐transplant. Median creatinine levels in Study 1 were 133 and 132 μmol/L at 6 months in the 1.5 and 3 mg/day groups, respectively, and 130 μmol/L in both groups in Study 2. Biopsy‐proven acute rejection (BPAR) occurred in 25.0% and 15.2% of patients in the 1.5 and 3 mg/day groups in Study 1, and 13.7% and 15.1% in Study 2. Incidence of BPAR was significantly higher in patients with an everolimus trough < 3 ng/mL. There were no significant between‐group differences in the composite endpoint of BPAR, graft loss or death, nor any significant between‐group differences in adverse events in either study. Concentration‐controlled everolimus with low‐exposure CsA provided effective protection against rejection with good renal function.

Comparing Mycophenolate Mofetil Regimens for de Novo Renal Transplant Recipients: The Fixed-Dose Concentration-Controlled Trial

Background. Fixed-dose mycophenolate mofetil (MMF) reduces the incidence of acute rejection after solid organ transplantation. The Fixed-Dose Concentration Controlled trial assessed the feasibility and potential benefit of therapeutic drug monitoring in patients receiving MMF after de novo renal transplant. Methods. Patients were randomized to a concentration-controlled (n=452; target exposure 45 mg hr/L) or a fixed-dose (n=449) MMF-containing regimen. The primary endpoint was treatment failure (a composite of biopsy-proven acute rejection [BPAR], graft loss, death, or MMF discontinuation) by 12 months posttransplantation. Results. Mycophenolic acid (MPA) exposures for both groups were similar at most time points and were below 30 mg hr/L in 37.3% of patients at day 3. There was no difference in the incidence of treatment failure (25.6% vs. 25.7%, P=0.81) or BPAR (14.9% vs. 15.5%, P>0.05) between the concentration-controlled and the fixed-dose groups, respectively. We did find a significant relationship between MPA-area under the concentration–time curve on day 3 and the incidence of BPAR in the first month (P=0.009) or in the first year posttransplantation (P=0.006). For later time points (day 10, month 1) there was no significant relationship between area under the concentration–time curve and BPAR (0.2572 and 0.5588, respectively). Conclusions. There was no difference in the incidence of treatment failure between the concentration-controlled and the fixed-dose groups. The applied protocol of MMF dose adjustments based on target MPA exposure was not successful, partly because physicians seemed reluctant to implement substantial dose changes. Current initial MMF doses underexpose more than 35% of patients early after transplantation, increasing the risk for BPAR.

Randomized controlled trial of sirolimus for renal transplant recipients at high risk for nonmelanoma skin cancer.

Sirolimus has antineoplastic effects and may reduce skin cancer rates in kidney transplant patients. This prospective, multicenter, randomized, open‐label, controlled trial randomized 86 kidney transplant recipients (≥1 year posttransplant) with history of nonmelanoma skin cancer (NMSC) to continue calcineurin inhibitor (CNI) or convert to sirolimus. Patients were stratified by number of NMSC lesions (0–5, 6–20) in previous year. Primary end point was number of biopsy‐confirmed new NMSC lesions per patient‐year. Yearly NMSC rate was significantly lower with sirolimus (1.31 vs. 2.48 lesions/patient‐year; p = 0.022). Squamous cell carcinoma occurred at a lower rate in the sirolimus versus CNI group (p = 0.038); basal cell carcinoma rate was similar in both. A lower proportion of patients receiving sirolimus developed new or recurrent NMSC (56.4% vs. 80.9%; p = 0.015) or new squamous cell carcinoma (41.0% vs. 70.2%; p = 0.006). No sirolimus patients and one CNI continuation patient experienced acute rejection. Incidence of treatment‐emergent adverse events was similar between groups; however, discontinuation rates related to adverse events were significantly higher with sirolimus (46.2% vs. 0%; p < 0.001). In kidney transplant recipients with history of NMSC, conversion from CNI to sirolimus reduced rates of NMSC, without increasing acute rejection risk.

Randomized, Controlled Trial of Topical Exit-Site Application of Honey (Medihoney) versus Mupirocin for the Prevention of Catheter-Associated Infections in Hemodialysis Patients

The clinical usefulness of hemodialysis catheters is limited by increased infectious morbidity and mortality. Topical antiseptic agents, such as mupirocin, are effective at reducing this risk but have been reported to select for antibiotic-resistant strains. The aim of the present study was to determine the efficacy and the safety of exit-site application of a standardized antibacterial honey versus mupirocin in preventing catheter-associated infections. A randomized, controlled trial was performed comparing the effect of thrice-weekly exit-site application of Medihoney versus mupirocin on infection rates in patients who were receiving hemodialysis via tunneled, cuffed central venous catheters. A total of 101 patients were enrolled. The incidences of catheter-associated bacteremias in honey-treated (n = 51) and mupirocin-treated (n = 50) patients were comparable (0.97 versus 0.85 episodes per 1000 catheter-days, respectively; NS). On Cox proportional hazards model analysis, the use of honey was not significantly associated with bacteremia-free survival (unadjusted hazard ratio, 0.94; 95% confidence interval, 0.27 to 3.24; P = 0.92). No exit-site infections occurred. During the study period, 2% of staphylococcal isolates within the hospital were mupirocin resistant. Thrice-weekly application of standardized antibacterial honey to hemodialysis catheter exit sites was safe, cheap, and effective and resulted in a comparable rate of catheter-associated infection to that obtained with mupirocin (although the study was not adequately powered to assess therapeutic equivalence). The effectiveness of honey against antibiotic-resistant microorganisms and its low likelihood of selecting for further resistant strains suggest that this agent may represent a satisfactory alternative means of chemoprophylaxis in patients with central venous catheters.

OBESITY IS ASSOCIATED WITH WORSENING CARDIOVASCULAR RISK FACTOR PROFILES AND PROTEINURIA PROGRESSION IN RENAL TRANSPLANT RECIPIENTS

Obesity is associated with adverse cardiovascular (CV) parameters and may be involved in the pathogenesis of allograft dysfunction in renal transplant recipients (RTR). We sought the spectrum of body mass index (BMI) and the relationships between BMI, CV parameters and allograft function in prevalent RTR. Data were collected at baseline and 2 years on 90 RTR (mean age 51 years, 53% male, median transplant duration 7 years), categorized by BMI (normal, BMI ≤ 24.9 kg/m2; pre‐obese, BMI 25–29.9 kg/m2; obese, BMI ≥ 30 kg/m2). Proteinuria and glomerular filtration rate (eGFRMDRD) were determined.

12-month safety and efficacy of everolimus with reduced exposure cyclosporine in de novo renal transplant recipients

The proliferation signal inhibitor everolimus (Certican), has demonstrated efficacy with full‐dose cyclosporine (CsA) (Neoral®). Two multicenter randomized controlled studies were performed to compare 12‐month efficacy and safety of everolimus 1.5 and 3.0 mg/day with reduced‐dose CsA. Study 1 enrolled 237 de novo renal allograft recipients, randomizing 222 nonblack patients to either everolimus 1.5 or 3.0 mg/day, with the Neoral® dose guided by C2 (monitoring of CsA concentration 2 h after dosing). Study 2 had a similar protocol, with basiliximab included, enrolling 256 recipients and randomizing 243 nonblack patients. In Study 1, there was a lower incidence of acute rejection in nonblack patients on 3 mg/day (16.4%) compared with 1.5 mg/day (25.9%), P = 0.08. In Study 2, the inclusion of basiliximab lowered the overall incidence of acute rejection; 14.3% of nonblack patients (3 mg/day) and 13.6% of nonblack patients (1.5 mg/day) had acute rejection by 12 months (P =0.891). Renal function was preserved throughout the study, with no differences observed between groups within studies. Everolimus was well tolerated with no significant differences between doses. Everolimus, in combination with reduced‐dose Neoral®, demonstrated efficacy and was well tolerated. Basiliximab allows for utilization of lower doses of everolimus with reduced dosing of Neoral®.

Kidney Transplant Rejection in Australia and New Zealand: Relationships Between Rejection and Graft Outcome

Although acute rejection rates have fallen over time, how this relates to graft outcomes is not known. Using data from the ANZDATA Registry, we examined associations of rejection within six months of transplantation with graft and patient outcomes among kidney‐only transplants performed between April 1997 and December 2004 in Australia and New Zealand. Associations of biopsy histology with outcomes of the rejection episode were also examined. Outcomes were examined among 4325 grafts with 1961 rejection episodes in total. Crude rejection rates have fallen by one‐third over that time, but rates of graft survival are constant. The occurrence of acute rejection was associated with an increased risk of graft loss after 6 months (HR, adjusted for donor and recipient characteristics, 1.69 [1.36–2.11], p < 0.001). Late rejection (first rejection ≥90 days) was associated with higher risk of graft loss (adjusted HR 2.46 [1.70–3.56], p < 0.001). Vascular rejection was also associated with a higher risk of graft loss 2.07 [95% CI 1.60–2.68], p < 0.001. The occurrence of acute rejection is associated with an ongoing increased risk of graft loss, particularly if that episode occurred late or included vascular rejection. The reduced rates of rejection have not been associated with improved graft survival.

Metabolic syndrome in severe chronic kidney disease: Prevalence, predictors, prognostic significance and effects of risk factor modification

Background:  Metabolic syndrome (MS) is a significant risk factor for cardiovascular disease, mortality and chronic kidney disease (CKD) in the general population. However, the prevalence, predictors, prognostic value and treatment of MS in the CKD population have not been rigorously studied.

Sclerosing Peritonitis: Identification of Diagnostic, Clinical, and Radiological Features

Sclerosing peritonitis is a rare, but serious complication of peritoneal dialysis. To attempt the early identification of patients at risk of developing this life-threatening problem, we performed a cross-sectional study of 15 patients: five had died of sclerosing peritonitis, four had stopped peritoneal dialysis because sclerosing peritonitis was suspected, and six were considered to be at increased risk because of more than 4 years on peritoneal dialysis. We examined the duration of dialysis, number of episodes of peritonitis, strength of peritoneal dialysis bags, the type of dialysate, and the use of beta blockers. We also used a number of radiologic investigations, including abdominal x-ray, a measure of colonic transit using radiopaque markers, abdominal ultrasound, and computed tomography scanning. Of the clinical features, only duration of dialysis could be shown to be an important risk factor. We identified a number of radiologic features that we believe to be early signs of peritoneal sclerosis. The two computed tomography scans that were available from the deceased patients demonstrated peritoneal thickening, as did those from three of the four living patients who stopped peritoneal dialysis with suspected disease and from two of the six patients who had been on peritoneal dialysis for over 4 years. Ultrasound demonstrated a characteristic trilaminar appearance in four patients, but was unable to be demonstrated without peritoneal fluid in situ. Delayed colon transit was demonstrated in three of the four living patients with clinically suspected disease. Radiologic screening to detect sclerosing peritonitis early in high-risk patients requires further study.

Impact of obesity on renal transplant outcomes

SUMMARY:  Obesity is a frequent and important consideration to be taken into account when assessing patient suitability for renal transplantation. In addition, posttransplant obesity continues to represent a significant challenge to health care professionals caring for renal transplant recipients. Despite the vast amount of evidence that exists on the effect of pretransplant obesity on renal transplant outcomes, there are still conflicting views regarding whether obese renal transplant recipients have a worse outcome, in terms of short‐ and long‐term graft survival and patient survival, compared with their non‐obese counterparts. It is well established that any association of obesity with reduced patient survival in renal transplant recipients is mediated in part by its clustering with traditional cardiovascular risk factors such as hypertension, dyslipidaemia, insulin resistance and posttransplant diabetes mellitus, but what is not understood is what mediates the association of obesity with graft failure. Whether it is the higher incidence of cardiovascular comorbidities jeopardising the graft or factors specific to obesity, such as hyperfiltration and glomerulopathy, that might be implicated, currently remains unknown. It can be concluded, however, that pre‐ and posttransplant obesity should be targeted as aggressively as the more well‐established cardiovascular risk factors in order to optimize long‐term renal transplant outcomes.