Achieving Chronic Kidney Disease Treatment Targets in Renal Transplant Recipients: Results From a Cross-Sectional Study in Spain

Bone Mineral Disease After Kidney Transplantation

Chronic kidney disease-mineral bone disorder (CKD-MBD) after kidney transplantation is a mix of pre-existing disorders and new alterations. The final consequences are reflected fundamentally as abnormal mineral metabolism (hypercalcemia, hypophosphatemia) and bone alterations [high or low bone turnover disease (as fibrous osteitis or adynamic bone disease), an eventual compromise of bone mineralization, decrease bone mineral density and bone fractures]. The major cause of post-transplantation hypercalcemia is the persistence of severe secondary hyperparathyroidism, and treatment options include calcimimetics or parathyroidectomy. On turn, hypophosphatemia is caused by both the persistence of high blood levels of PTH and/or high blood levels of FGF23, with its correction being very difficult to achieve. The most frequent bone morphology alteration is low bone turnover disease, while high-turnover osteopathy decreases in frequency after transplantation. Although the pathogenic mechanisms of these abnormalities have not been fully clarified, the available evidence suggests that there are a number of factors that play a very important role, such as immunosuppressive treatment, persistently high levels of PTH, vitamin D deficiency and hypophosphatemia. Fracture risk is four-fold higher in transplanted patients compared to general population. The most relevant risk factors for fracture in the kidney transplant population are diabetes mellitus, female sex, advanced age (especially > 65 years), dialysis vintage, high PTH levels and low phosphate levels, osteoporosis, pre-transplant stress fracture and high doses or prolonged steroids therapy. Treatment alternatives for CKD-MBD after transplantation include minimization of corticosteroids, use of calcium and vitamin D supplements, antiresorptives (bisphosphonates or Denosumab) and osteoformers (synthetic parathyroid hormone). As both mineral metabolism and bone disorders lead to increased morbidity and mortality, the presence of these changes after transplantation has to be prevented (if possible), minimized, diagnosed, and treated as soon as possible.

Clinical outcomes of incident peritoneal dialysis patients coming from kidney transplantation program: A case-control study

Introduction

Brazil ranks second in the absolute number of transplantations in the world. Despite improvements in graft survival, many patients will progress to graft loss and return to dialysis. Concerns exist regarding adverse clinical outcomes in this population when undergone peritoneal dialysis (PD).

Objective

To compare the occurrence of mortality, technique failure, and peritonitis among incident patients in PD coming from either Tx or pre-dialysis treatment.

Methodology

A retrospective study in which 47 adult patients with Tx failure (Tx group) were matched for age, gender, diabetes mellitus (DM), modality and start year of PD, with 1:1 predialysis patient (nTx group). The Fine-Gray competing risk model was used to analyze mortality and technique failure.

Results

Compared to nTx, the Tx group had a lower body mass index, serum potassium, and albumin concentrations. A higher ferritin level, transferrin saturation and the number of patients with positive serology for viral hepatitis were also observed in the Tx group. In the multivariate analysis, patients of the Tx group had 4.4-times higher risk of death (p = 0.007), with infection as the main cause. Technique failure and peritonitis were similar in both groups.

Conclusion

Previous Tx is a risk factor for mortality but not for technique failure or peritonitis in incident patients on a PD program.

Assessment of a Dedicated Transplant Low Clearance Clinic and Patient Outcomes on Dialysis After Renal Allograft Loss at 2 UK Transplant Centers

Background

Low clearance transplant clinics (LCTCs) are recommended for the management of recipients with a failing kidney transplant (RFKT) but data to support their use is limited. We conducted a retrospective study to assess management of RFKT at 2 transplant centers, 1 with a LCTC (center A) and 1 without (center B).

Methods

Patients who transitioned to an alternative form of renal replacement therapy (RRT) between January 1, 2012, and November 30, 2016, were included. Patients with graft failure within a year of transplantation or due to an unpredictable acute event were excluded. Clinical data were collected after review of medical records.

Results

One hundred seventy-nine patients (age, 48.6 ± 13.4 years, 99 [55.3%] male, and mean transplant duration 10.3 ± 7.8 years) were included. RRT counseling occurred in 79 (91%) and 68 (74%) patients at centers A and B (P = 0.003), at median 135 (61-319) and 133 (69-260) days before dialysis after graft loss (P = 0.92). Sixty-one (34.1%) patients were waitlisted for retransplantation; 18 (32.7%) nonwaitlisted patients were still undergoing workup at center A compared with 37 (58.7%) at center B (P = 0.028). Preemptive retransplantation occurred in 4 (4.6%) and 5 (5.4%) patients at centers A and B (P = 0.35). At 1 year after initiation of dialysis after graft loss, 11 (15.3%) and 11 (17.2%) patients were retransplanted (P = 0.12), and mortality was 6.6% overall.

Conclusions

A dedicated LCTC improved RRT counseling and transplant work-up but did not lead to improved rates of retransplantation. Earlier consideration of retransplantation in LCTCs is required to improve RFKT outcomes.

Early low-dose erythropoiesis-stimulating agent therapy and progression of moderate chronic kidney disease: a randomized, placebo-controlled trial

Background

It is unknown whether early intervention with low-dose erythropoiesis-stimulating agents (ESAs) in non-anaemic patients delays progression of chronic kidney disease (CKD).

Methods

In a single-blind, 24-month trial, adults with estimated glomerular filtration rate (eGFR) 30–59 mL/min/1.73 m2 and either Type 2 diabetes mellitus or previous kidney transplantation were randomized to low-dose continuous erythropoiesis receptor activator (CERA; monthly dose 30–75 µg; n = 115) or placebo (n = 120). The primary endpoint was the annual change in eGFR (abbreviated Modification of Diet in Renal Disease formula).

Results

Mean (standard deviation) eGFR was 40.7 (9.8) mL/min/1.73 m2 versus 39.8 (9.2) mL/min/1.73 m2 at baseline for CERA and placebo, respectively, and 39.0 (11.6) g/dL versus 39.7 (10.6) g/dL at the final visit. The median (interquartile range) annual reduction in eGFR was 0.5 (−2.2, 3.8) mL/min/1.73 m2 with CERA versus 0.4 (−2.0, 3.2) mL/min/1.73 m2 with placebo (P = 0.657). No significant difference in the annual change in eGFR was observed between treatment groups in the subpopulations with Type 2 diabetes or kidney transplant. Adverse events with a suspected relation to study drug occurred in 22.0% and 16.2% of patients randomized to CERA or placebo, respectively, and adverse events led to study drug discontinuation in 11.0% and 8.5% of patients.

Conclusions

Patients with moderate CKD and Type 2 diabetes or previous kidney transplantation showed stable renal function that was unaffected by administration of low-dose ESA. In addition, there was no clinically meaningful effect of 2-year low-dose ESA treatment on albuminuria, an important surrogate marker of kidney injury.

A systems-based approach to managing blood pressure in children following kidney transplantation

Hypertension is one of the most common and well-known complications following kidney transplantation in children. Yet, despite numerous available therapies many pediatric kidney transplant recipients continue to have poorly controlled blood pressure, suggesting that traditional approaches to blood pressure management in this population might be inadequate. Over the last two decades, the Chronic Care Model has been developed to improve chronic illness outcomes through delivery system design and clinical information systems that support patient self-management and provider decision-making. In this educational review we discuss key elements of managing blood pressure following pediatric kidney transplantation and suggest ways that they may be reliably implemented into clinical practice using principles from the Chronic Care Model.

Is Kidney Transplantation a Better State of CKD? Impact on Diagnosis and Management

Patients with CKD are at increased risk for cardiovascular events, hospitalizations, and mortality. Kidney transplantation (KTx) is the preferred treatment for end-stage kidney disease. Although comorbidities including anemia and bone and mineral disease improve or are even halted after KTx, kidney transplant recipients carry higher cardiovascular mortality risk than the general population, as well as an increased risk of infections, malignancies, fractures, and obesity. When comparing CKD with CKD after transplantation (CKD-T), the rate of decline of estimated glomerular filtration rate (eGFR) is significantly lower in CKD-T. Higher rate of decline of eGFR has been associated with increased risk of mortality. However, due to the significant increased risk of mortality due to cardiovascular events, infections, and malignancies, many kidney transplant recipients may not benefit of decline in the rate of eGFR. Patients with CKD-T are a unique subset of patients with multiple traditional and transplant-specific risk factors. Proper management and appropriate preventive health measures may improve long-term patient and allograft survival in patients with CKD-T.

Laboratory use of hepcidin in renal transplant recipients

Hepcidin is a small peptide with a critical role in cellular iron homeostasis, as it regulates utilization of stored iron and antimicrobial defense in inflammation (bacterial and fungal). Since it was isolated in 2000, and especially in the last decade, numerous studies aimed to evaluate the clinical use of plasma and urine hepcidin as a marker of anemia, especially anemia of chronic disease and post-transplant anemia (PTA). Hepcidin regulation is delicately tuned by two inflammatory pathways activated by interleukin-6 (IL-6) and bone morphogenic proteins (BMPs) and iron regulated pathway sensitive to circulating transferin-iron (TR-Fe) complex. BMP-mediated pathway and TR-Fe sensitive pathway seem to be connected by hemojuveline, a BMP co-factor that interacts with transferine receptor 2 (TRF2) in cases of high TR-Fe circulatory concentration. In addition to these regulatory mechanisms other regulators and signaling pathways are being extensively researched.
Hepcidin has been identified as an important contributor to morbidity and mortality in end stage renal disease (ESRD) but no such association has jet been found in case of PTA. However, there is an association between higher doses of erythropoiesis-stimulating agents (ESA) and mortality in the posttransplant period and the assumption that hepcidin might play a role in ESA resistance in PTA. Thus the review’s main goal was to summarize papers published on the association of hepcidin with PTA, give up-to-date information on hepcidin regulation and on potential therapeutics that optimize hepcidin regulation. We also compared the performances of tests for hepcidin determination and reviewed research on immunosuppressants’ (IS) effect on hepcidin concentration.

Mineral metabolism disorders, vertebral fractures and aortic calcifications in stable kidney transplant recipients: The role of gender (EMITRAL study)

BACKGROUND AND OBJECTIVES

The relationship between mineral metabolism disorders, bone fractures and vascular calcifications in kidney transplant recipients has not been established.

METHOD

We performed a cross-sectional study in 727 stable recipients from 28 Spanish transplant clinics. Mineral metabolism parameters, the semi-quantification of vertebral fractures and abdominal aortic calcifications were determined centrally.

RESULTS

Vitamin D deficiency (25OHD3<15ng/ml) was more common in female recipients at CKD-T stages I-III (29.6% vs 44.4%; p=0.003). The inverse and significant correlation between 25OHD3 and PTH was gender-specific and women exhibited a steeper slope than men (p=0.01). Vertebral fractures (VFx) with deformity grade ≥2 were observed in 15% of recipients. Factors related to VFx differed by gender; in males, age (OR 1.04; 95% CI 1.01-1.06) and CsA treatment (OR: 3.2; 95% CI: 1.6-6.3); in females, age (OR 1.07; 95% CI: 1.03-1.12) and PTH levels (OR per 100pg/ml increase: 1.27; 95% CI: 1.043-1.542). Abdominal aortic calcifications were common (67.2%) and related to classical risk factors but not to mineral metabolism parameters.

CONCLUSIONS

Vitamin D deficiency is more common among female kidney transplant recipients at earlier CKD-T stages, and it contributes to secondary hyperparathyroidism. Prevalent vertebral fractures are only related to high serum PTH levels in female recipients.

Association of Extrarenal Adverse Effects of Posttransplant Immunosuppression With Sex and ABCB1 Haplotypes

Extrarenal adverse effects (AEs) associated with calcineurin inhibitor (CNI) and mycophenolic acid (MPA) occur frequently but are unpredictable posttransplant complications. AEs may result from intracellular CNI accumulation and low activity of P-glycoprotein, encoded by the ABCB1 gene. Since ABCB1 single nucleotide polymorphisms (SNPs) and sex influence P-glycoprotein, we investigated haplotypes and extrarenal AEs. A prospective, cross-sectional study evaluated 149 patients receiving tacrolimus and enteric coated mycophenolate sodium or cyclosporine and mycophenolate mofetil. Immunosuppressive AE assessment determined individual and composite gastrointestinal, neurologic, aesthetic, and cumulative AEs. Lipids were quantitated after 12-hour fast. ABCB1 SNPs: c.1236C>T (rs1128503), c.2677G>T/A (rs2032582), and c.3435C>T (rs1045642) were determined with haplotype associations computed using the THESIAS program, and evaluated by immunosuppression, sex and race using multivariate general linear models. Tacrolimus patients exhibited more frequent and higher gastrointestinal AE scores compared with cyclosporine with association to CTT (P = 0.018) and sex (P = 0.01). Aesthetic AE score was 3 times greater for cyclosporine with TTC haplotype (P = 0.005). Females had higher gastrointestinal (P = 0.022), aesthetic (P < 0.001), neurologic (P = 0.022), and cumulative AE ratios (P < 0.001). Total cholesterol (TCHOL), low-density lipoproteins (LDL), and triglycerides were higher with cyclosporine. The TTC haplotype had higher TCHOL (P < 0.001) and LDL (P = 0.005). Higher triglyceride (P = 0.034) and lower high-density lipoproteins (P = 0.057) were associated with TTT with sex-adjusted analysis. ABCB1 haplotypes and sex were associated with extrarenal AEs. Using haplotypes, certain female patients manifested more AEs regardless of CNI. Haplotype testing may identify patients with greater susceptibility to AEs and facilitate CNI individualization.

Prevalence and predictors of aortic dilation as a novel cardiovascular complication in children with end-stage renal disease

Background: Cardiovascular disease is the leading cause of death in children with end-stage renal disease (ESRD). Isolated aortic dilation (AD) is rare in children. We aimed to determine the prevalence and the risk factors for AD in children with ESRD. Methods and study design: We reviewed records of all ESRD patients followed at our institution from January 2007 to October 2012. AD was defined as Z-score > 2 in the dimension of at least one of the following echocardiographic aortic parameters: annulus, root at the sinus, sino-tubular junction, ,or ascending aorta. Results: The records of 78 patients on dialysis and 19 kidney transplant recipients were available. 30 patients (30.9%) had AD. Multivariate analysis revealed independent associations of AD with body mass index (BMI) Z-score (OR = 0.52, 95% confidence interval (CI): 0.35 – 0.78) and ESRD secondary to glomerular disease (OR = 4.58, 95% CI: 1.45 – 14.46). We developed a classification and regression tree (CART) model to identify patients at low vs. high AD risk. Our model classified 62 patients of the cohort (64%) to be high- or low-risk, with a positive predictive value of 89% and a negative predictive value of 100%. Conclusion: Our data suggest that AD, as a possible marker of aortopathy and early aneurysm formation, is a novel and prevalent cardiovascular complication in ESRD children. Glomerular disease and low BMI Z-score appear to be potent predictors. CART modeling helps identify high-risk children, potentially guiding decisions regarding targeted echocardiographic evaluations.

The quality of cardiovascular disease care for adolescents with kidney disease: a Midwest Pediatric Nephrology Consortium study

BACKGROUND

Cardiovascular disease is the leading cause of increased mortality for adolescents with advanced kidney disease. The quality of preventive cardiovascular care may impact long-term outcomes for these patients.

METHODS

We reviewed the records of 196 consecutive adolescents from eight centers with pre-dialysis chronic kidney disease, on dialysis or with a kidney transplant, who transferred to adult-focused providers. We compared cardiovascular risk assessment and therapy within and across centers. Predictors of care were assessed using multilevel models.

RESULTS

Overall, 58 % (range 44-86 %; p = 0.08 for variance) of five recommended cardiovascular risk assessments were documented. Recommended therapy for six modifiable cardiovascular risk factors was documented 57 % (26-76 %; p = 0.09) of the time. Of these patients, 30 % (n = 59) were reported to go through formal transition which was independently associated with a 21 % increase in composite cardiovascular risk assessment (p < 0.001). Transfer after 2006 and kidney transplant status were also associated with increased cardiovascular risk assessment (p < 0.01 and p = 0.045, respectively).

CONCLUSIONS

Adolescents with kidney disease receive suboptimal preventive cardiovascular care, that may contribute to their high risk of future cardiovascular mortality. A great opportunity exists to improve outcomes for children with kidney disease by improving the reliability of preventive care that may include formal transition programs.

Reliable individualized monitoring improves cholesterol control in kidney transplant recipients

OBJECTIVE

To develop and evaluate a system for reliable and efficient individualized risk-based monitoring of cholesterol and 11 other tests after kidney transplantation in children.

METHODS

We identified system components that drive reliable individualized monitoring and used quality improvement methods to develop and implement interventions, including (1) monitoring schedules individualized by dyslipidemia risk assigned to each patient, (2) automated previsit decision support from our electronic medical record, (3) standardized work flow and responsibility, and (4) automated forwarding of results to providers. We measured the proportion of patients due for cholesterol testing who had it performed within 1 week of their clinic visit and the proportion of patients in our population who achieved low-density lipoprotein (LDL) cholesterol control at baseline and for 2 years after improved monitoring.

RESULTS

The proportion of visits in which cholesterol monitoring was completed when indicated improved from 80% to 98% within 8 months and was sustained for more than 1 year. The number of patients with controlled LDL (<130 mg/dL, 3.3 mmol/L) improved from 44 (71%) of 62 at the start of our project to 58 (94%) of 62 (P = .002) at an average follow-up of 24 months.

CONCLUSIONS

Using quality improvement and health information technology, we achieved sustained, reliable and efficient personalized monitoring of cholesterol and 11 other tests. This approach enabled substantial improvement in LDL cholesterol control. Structured methods of system redesign that leverage information technology systems hold promise for rapidly achieving reliable individualized care in other settings.

Clinical profile and post-transplant anaemia in renal transplant recipients restarting dialysis after a failed graft: changing trends between 2001 and 2009

BACKGROUND

The aim of this study was to compare the clinical profile, outcome and the prevalence and management of anaemia between two cohorts of renal transplant patients with graft failure restarting dialysis in 2001 and 2009.

METHODS

Cross-sectional, observational, retrospective and multicentre study of 397 patients in the 2001 cohort and 222 in the 2009 cohort. Data were recorded at 0, 3, 6, 9 and 12 months before the onset of dialysis resumption and during the first 90 days after restarting dialysis (mortality and hospital admission).

RESULTS

Patients in the 2009 cohort were older at the time of inclusion in the study and transplantation, and restarted dialysis therapy with a significantly better glomerular filtration rate. In both cohorts, there was a rapid deterioration of renal function with statistically significant differences in serum creatinine and glomerular filtration rate between the monthly intervals -12 and 0. The mean haemoglobin value at -12 months was 11.6 g/dL [7.2 mmol/L] in the 2001 cohort when compared with 12.3 g/dL [7.6 mmol/L] in the 2009 cohort, and at the time of restarting dialysis 9.6 g/dL [6.0 mmol/L] versus 10.6 g/dL [6.6 mmol/L]. The percentage of patients treated with erythropoiesis-stimulating agents, at any time during the 12 months before readmission to dialysis, increased significantly from 61.5% in the 2001 cohort to 96% in the 2009 cohort. There were no significant differences between the 2001 and 2009 cohorts in mortality rate (8.8 versus 9.0%) or hospital admission (31.5 versus 31.1%) during the study time.

CONCLUSIONS

At restarting dialysis, the proportion of patients with anaemia (and its severity) due to progressive graft nephropathy decreased over the past 8 years, increasing significantly the percentage of patients treated with erythropoietin. Differences in morbimortality after dialysis resumption were not observed, this is probably due to an increase in the age of donors and recipients.

Treatment of anemia with erythropoietin-stimulating agents in kidney transplant recipients and chronic kidney disease-another drawback of immunosuppression?

Anemia is more prevalent in allograft recipients compared with glomerular filtration rate (GFR) matched patients with chronic kidney diseases. There is a paucity of data concerning the correction of anemia in the posttransplant period with erythropoietin-stimulating agents (ESA). The aim of this study was to compare the iron status, kidney function, inflammatory state, use of drugs affecting erythropoiesis (immunosuppressants ACEi/ARB) and correction of anemia using ESA in a chronic kidney disease (CKD) population versus kidney transplant recipients. We included 67 patients treated with ESA including 17 after kidney transplantation. CKD Patients with native kidneys were significantly older than allograft recipients (mean age 69 versus 51 years; P < .001, and despite similar serum creatinine and iron parameters showed an estimated lower GFR (19 mL/min versus 23 mL/min; P < .05). Median time of ESA therapy was similar among patients with native kidney CKD versus kidney recipients, but they achieved a significantly higher hemoglobin (11.04 versus 10.36 g/dL; P < .05). There was no difference between patients administered or not a mammalian target of rapamycin antagonist. None of the patients with native kidney CKD received immunosuppressive therapy, but they were prescribed ACEi more often than kidney recipients. The higher degree of anemia in kidney allograft recipient is the most probably attributed to the use of immunosuppressive drugs, despite their better kidney function and comparable iron status. This study suggested that higher doses of ESA should be employed to anemia in kidney transplant recipients.

Anemia and erythrocytosis in patients after kidney transplantation

Anemia is a highly prevalent disorder in recipients of renal allografts. Despite its frequent occurrence, there is still uncertainty with regard to treatment targets and treatment options. This includes questions on appropriate iron management, the choice and dosage of erythropoietin stimulating agents, criteria for the timing of treatment initiation and the targeted hemoglobin values. The review summarizes available data on recent therapeutic strategies for post transplant anemia, as well as for post transplant erythrocytosis, another hematological disorder, that has decreased in recent years.

Diagnosis and prevention of chronic kidney allograft loss

Kidney transplantation is the best possible treatment for many patients with end-stage renal failure, but progressive dysfunction and eventual allograft loss with return to dialysis is associated with increased mortality and morbidity. Immune injury from acute or chronic rejection and non-immune causes, such as nephrotoxicity from calcineurin inhibitors, ischaemia-reperfusion injury, recurrent glomerular disease, and allograft BK viral infection, are potential threats. Serial monitoring of renal function enables early recognition of chronic allograft dysfunction, and investigations such as therapeutic drug concentrations, urinalysis, imaging, and a diagnostic biopsy should be undertaken before irreversible nephron loss has occurred. Specific interventions targeting the pathophysiological cause of dysfunction include strengthening of immunosuppression for chronic rejection, or calcineurin inhibitor minimisation, substitution, or elimination if nephrotoxicity dominates. Recommended proactive preventive measures are control of hypertension, proteinuria, dyslipidaemia, diabetes, smoking, and other comorbidities. Strategies to maintain transplant function and improve long-term graft survival are important goals of translational research.

Long-term graft function changes in kidney transplant recipients

Background. Monitoring changes in glomerular filtration rate (GFR) is the recommended method for assessing the progression of kidney disease. The aim of this study was to assess the decline of graft function defined by the annualized change in GFR and the factors which affect it.Methods. Four thousand four hundred and eighty-eight patients, transplanted during the years 1990, 1994, 1998 and 2002 in 34 centres in Spain with allograft survival of at least 1 year, were included in the study. GFR was estimated using the four-variable equation of the Modification of Diet in Renal Diseases (MDRD) study. Linear mixed effects model was applied to determine the relation between the covariates and the annualized change in GFR after transplantation.Results. The average GFR at 12 months was 51.4 +/- 18.9 mL/min/1.73 m(2); most patients were in stage 3 of chronic kidney disease classification. The average patient slope, calculated in a linear model with varying-intercept and varying-slope without covariates, was -1.12 +/- 0.05 mL/min/year (slope +/- standard error). Some variables were related to both the 12-month GFR (intercept) and the slope: recipient gender, hepatitis C virus (HCV) status, estimated GFR (eGFR) at 3 months and proteinuria at 12 months. Some variables were only related to the slope of eGFR: time on dialysis, primary renal disease and immunosuppression. Others affected only the 12-month GFR: donor age, delayed graft function, acute rejection and systolic blood pressure at 12 months. Higher graft function at 3 months had a negative impact on the GFR slope. Cyclosporine-based immunosuppression had a less favourable effect on the rates of change in allograft function.Conclusions. There was a slow decline in GFR. Poor graft function was not associated with an increased rate of decline of allograft function. Immunosuppression with cyclosporine displayed the worst declining GFR rate.

Immunosuppressive drugs in kidney transplantation: impact on patient survival, and incidence of cardiovascular disease, malignancy and infection

Renal transplant recipients have increased mortality rates when compared with the general population. The new immunosuppressive drugs have improved short-term patient survival up to 95% at 1-2 years, but these data have to be confirmed in long-term follow-up. Furthermore, no particular regimen has proved to be superior over others with regard to patient survival. Cardiovascular diseases are the most common cause of mortality in renal transplant recipients and while no immunosuppressive drug has been directly associated with cardiovascular events, immunosuppressive drugs have different impacts on traditional risk factors. Corticosteroids and ciclosporin are the agents with the most negative impact on weight gain, blood pressure and lipids. Tacrolimus increases the risk of new-onset diabetes mellitus. Sirolimus and everolimus have the most impact on risk factors for post-transplant hyperlipidaemia. Modifications in immunosuppression could improve the cardiovascular profile but there is little evidence regarding the beneficial effects of these changes on patient outcomes. Malignancies are also an increasing cause of mortality, overtaking cardiovascular disease in some series. Induction therapy, azathioprine and calcineurin inhibitors (CNIs) are probably the immunosuppressive agents most linked with post-transplant malignancies. Mycophenolate mofetil (MMF) has no negative impact on the incidence of malignancies. Target of rapamycin (mTOR) inhibitors have antioncogenic properties and they are associated with a lower incidence of malignancies. In addition, these agents have been recommended for use to decrease the dose or withdrawal of CNIs in patients with malignancies. Infections are still an important cause of morbidity and mortality in renal transplant recipients. Some immunosuppressive agents such as MMF increase the incidence of cytomegalovirus infection and the need for prophylactic measures in risk recipients. The use of potent immunosuppressive therapy has resulted in the appearance of BK virus nephropathy, which progresses to graft failure in a high percentage of patients. Although first associated with tacrolimus and MMF immunosuppression, recent data suggest that BK nephropathy appears with any kind of triple therapy. In conclusion, reducing risk factors for patient death should be a major target to improve outcomes after renal transplantation. Effort should be made to control cardiovascular diseases, malignancies and infections with improved use of immunosuppressive drugs. Preliminary results with belatacept suggest its safety and efficacy, and open new perspectives in the immunosuppression of de novo renal transplant recipients.

Two-year follow-up of a prospective study of circulating regulatory T cells in renal transplant patients

CD4(+)CD25(high)FOXP3(+) regulatory T cells (Tregs) are involved in alloreactivity and may be associated with protection from rejection. Their quantification in peripheral blood could guide clinicians in the management of renal transplant patients. Thus, we prospectively monitored the levels and in vitro suppression of circulating Tregs in 33 renal transplant patients from deceased donors within the first two yr of transplantation. Patients received maintenance immunosuppression with tacrolimus, mofetil mycophenolate and prednisolone. Results showed that peripheral blood Tregs were significantly lower six months after transplantation and recovered to almost basal levels at first post-transplant year. The number of circulating Tregs increased significantly over basal levels afterwards. The decrease in circulating Tregs at six months may be explained by the high load of tacrolimus, as demonstrated by the inverse correlation between the blood concentration of Tregs and tacrolimus. Likewise, nine patients treated with anti-CD25 antibodies showed higher numbers of Tregs at six months than those that did not, although differences were not observed later. In conclusion, circulating Tregs decrease in the first six months but recover thereafter up to two yr after kidney transplantation. Such a decrease is favored by high levels of tacrolimus but not by induction protocols with anti-CD25.