Conversion from cyclosporine to tacrolimus in patients at risk for chronic renal allograft failure: 60-month results of the CRAF Study. Transplantation. 2008;85:1261-1269. [PMID: 18475181 DOI: 10.1097/tp.0b013e31816b4388]

Immunosuppressive drug combinations after kidney transplantation and post-transplant diabetes: A systematic review and meta-analysis

Post-transplant diabetes mellitus (PTDM) is a frequent complication after kidney transplantation (KT). This systematic review investigated the effect of different immunosuppressive regimens on the risk of PTDM. We performed a systematic literature search in MEDLINE and CENTRAL for randomized controlled trials (RCTs) that included KT recipients with any immunosuppression and reported PTDM outcomes up to 1 October 2023. The analysis included 125 RCTs. We found no differences in PTDM risk within induction therapies. In de novo KT, there was an increased risk of developing PTDM with tacrolimus versus cyclosporin (RR 1.71, 95%CI [1.38-2.11]). No differences were observed between tacrolimus+mammalian target of rapamycin inhibitor (mTORi) and tacrolimus+MMF/MPA, but there was a tendency towards a higher risk of PTDM in the cyclosporin+mTORi group (RR 1.42, 95%CI [0.99-2.04]). Conversion from cyclosporin to an mTORi increased PTDM risk (RR 1.89, 95%CI [1.18-3.03]). De novo belatacept compared with a calcineurin inhibitor resulted in 50% lower risk of PTDM (RR 0.50, 95%CI [0.32-0.79]). Steroid avoidance resulted in 31% lower PTDM risk (RR 0.69, 95%CI [0.57-0.83]), whereas steroid withdrawal resulted in no differences. Immunosuppression should be decided on an individual basis, carefully weighing the risk of future PTDM and rejection.

Data mining and safety analysis of traditional immunosuppressive drugs: a pharmacovigilance investigation based on the FAERS database

OBJECTIVE

The purpose of this study aimed to explore the new and serious adverse events(AEs) of Tacrolimus(FK506), cyclosporine(CsA), azathioprine(AZA), mycophenolate mofetil(MMF), cyclophosphamide(CTX) and methotrexate(MTX), which have not been concerned.

METHODS

The FAERS data from January 2016 and December 2022 were selected for disproportionality analysis to discover the potential risks of traditional immunosuppressive drugs.

RESULTS

Compared with CsA, FK506 has more frequent transplant rejection, and is more related to renal impairment, COVID-19, cytomegalovirus infection and aspergillus infection. However, CsA has a high infection-related fatality rate. In addition, we also found some serious and rare AE in other drugs which were rarely reported in previous studies. For example, AZA is closely related to hepatosplenic T-cell lymphoma with high fatality rate and MTX is strongly related to hypofibrinogenemia.

CONCLUSION

The AEs report on this study confirmed that the results were basically consistent with the previous studies, but there were also some important safety signals that were inconsistent with or not mentioned in previous published studies.

EXPERT OPINION

The opinion section discusses some of the limitations and shortcomings, proposing the areas where more effort should be invested in order to improve the safety of immunosuppressive drugs.

Type 1 and other types of diabetes mellitus in the perioperative period. What the anaesthetist should know

Diabetes mellitus is often treated as a uniform disease in the perioperative period. Type 2 diabetes is most commonly encountered, and only a minority of surgical patients have been diagnosed with another type of diabetes. Patients with a specific type of diabetes can be particularly prone to perioperative glycaemic dysregulation. In addition, certain type-related features and pitfalls should be taken into account in the operating theatre. In this narrative review, we discuss characteristics of types of diabetes other than type 2 diabetes relevant to the anaesthetist, based on available literature and data from our clinic.

Early Conversion to Tacrolimus Vs Cyclosporine Continuation in Normally Functioning Kidney Allograft: A Single-Center Study

This study evaluated the effectiveness of early pre-emptive conversion from cyclosporine to tacrolimus in kidney transplant patients with normal graft function and in the absence of adverse effects of the initial cyclosporine. A historical cohort study of 166 patients who received deceased-donor kidney transplant between 2011 to 2017 was conducted. All the patients had been treated with cyclosporine (Sandimmune®) during their immediate post-transplantation period. At the time of hospital discharge, the patients were divided into 2 groups: patients with continued cyclosporine (Sandimmune®) treatment (n = 125) and the patients whose treatments converted from cyclosporine to tacrolimus (Prograf®) at discharge (n = 41). The 1-year graft function (p = 0.074), acute rejection (p = 0.566), and graft loss (p = 0.566) were not significantly different between two groups. The patients on tacrolimus had lower levels of cholesterol (p = 0.002) and diastolic blood pressure (p = 0.015). The long-term follow-up showed no significant difference in graft loss (p = 0.566). The patients received tacrolimus had higher all-cause mortality within the first year posttransplantation (p = 0.002) as well as long-term follow-up (p = 0.001). The continuation of initial cyclosporine might be a good option when the graft function is acceptable and the adverse effects are absent.

Kidney Allograft Fibrosis: Diagnostic and Therapeutic Strategies

Interstitial fibrosis with tubule atrophy (IF/TA) is the response to virtually any sustained kidney injury and correlates inversely with kidney function and allograft survival. IF/TA is driven by various pathways that include hypoxia, renin-angiotensin-aldosterone system, transforming growth factor (TGF)-β signaling, cellular rejection, inflammation and others. In this review we will focus on key pathways in the progress of renal fibrosis, diagnosis and therapy of allograft fibrosis. This review discusses the role and origin of myofibroblasts as matrix producing cells and therapeutic targets in renal fibrosis with a particular focus on renal allografts. We summarize current trends to use multi-omic approaches to identify new biomarkers for IF/TA detection and to predict allograft survival. Furthermore, we review current imaging strategies that might help to identify and follow-up IF/TA complementary or as alternative to invasive biopsies. We further discuss current clinical trials and therapeutic strategies to treat kidney fibrosis.Supplemental Visual Abstract; http://links.lww.com/TP/C141.

The impact of functional delayed graft function in the modern era of kidney transplantation - A retrospective study

The dialysis-based definition of Delayed Graft Function (dDGF) is not necessarily objective as it depends on the individual physician's decision. The functional definition of DGF (fDGF, the failure of serum creatinine to decrease by at least 10% daily on 3 consecutive days during the first week post-transplant), may be more sensitive to reflect recovery after the ischemia-reperfusion injury. We retrospectively analyzed both definitions in 253 deceased donor kidney transplant recipients for predicting death-censored graft failure as primary outcome, using eGFR < 25 ml/min/1.73 m² as a surrogate end-point for graft failure. Secondary outcome was a composite outcome that included graft failure as above and also patient's death. Median follow-up was 3.22 [2.38-4.21] years. Seventy-nine patients developed dDGF (31.2%) and 127 developed fDGF (50.2%). Sixty-three patients fulfilled criteria for both definitions (24.9%). At multivariable analysis, the two definitions were significantly associated with the primary [HR (95%CI) 2.07 (1.09-3.94), P = 0.026 for fDGF and HR (95%CI) 2.41 (1.33-4.37), P = 0.004 for dDGF] and the secondary composite outcome [HR (95%CI) 1.58 (1.01-2.51), P = 0.047 for fDGF and HR (95%CI) 1.67 (1.05-2.66), P = 0.028 for dDGF]. Patients who met criteria for both definitions had the worst prognosis, with a three-year estimates (95%CI) of survival from the primary and secondary outcomes of 2.31 (2.02-2.59) and 2.20 (1.91-2.49) years for fDGF+/dDGF+, in comparison with the other groups (P < 0.01 for trend). fDGF provides supplementary information about graft outcomes on top of the dDGF definition in a modern series of kidney transplantation.

Long-term Trends in the Clinicopathologic Features of Kidney Transplant Recipients With Graft Dysfunction

BACKGROUND

Graft biopsy is the gold standard for the differential diagnosis of graft dysfunction. The time interval between transplant surgery and biopsy often provides clinicians with diagnostic clues. However, the clinicopathologic features of late graft biopsy, especially those obtained at more than 5 years after kidney transplant, are not well understood.

MATERIALS AND METHODS

We retrospectively collected graft biopsy tissues obtained from kidney transplant recipients who underwent indication biopsy between February 2012 and March 2017. Patients were divided according to their post-transplant period, and their clinical characteristics, pathologic diagnosis, and Banff scores were compared across groups.

RESULTS

A total of 410 indication biopsy specimens obtained from 321 kidney transplant recipients were analyzed in this study. Overall, the incidence of T cell-mediated rejection, borderline rejection, and BK virus-associated nephropathy decreased while that of antibody-mediated rejection, nonspecific interstitial fibrosis and tubular atrophy, and glomerulonephritis increased over time. Most samples obtained over 5 years after kidney transplant exhibited chronic glomerular and tubulointerstitial injuries irrespective of their pathologic diagnosis. In patients whose post-transplant period was less than 5 years, urine protein-to-creatinine ratio was significantly elevated in the glomerulonephritis and chronic active antibody-mediated rejection groups only. In contrast, patients who underwent graft biopsy more than 5 years after kidney transplant showed significantly high levels of proteinuria irrespective of the pathologic diagnosis, and there was no statistical difference between groups.

CONCLUSION

We demonstrated that the etiology of graft dysfunction is largely influenced by the biopsy time point.

Impact of Conversion From Cyclosporine to Tacrolimus on Glucose Metabolism and Cardiovascular Risk Profiles in Long-Term Stable Kidney Transplant Recipients

BACKGROUND

Compared to tacrolimus, cyclosporine increases cardiovascular risk. Furthermore, tacrolimus has a negative effect on glucose metabolism compared to cyclosporine. This study investigated the effect of the conversion from cyclosporine to tacrolimus for immunosuppressive therapy on glucose metabolism and cardiovascular risk profiles in long-term stable kidney transplant recipients (KTRs).

METHODS

In this prospective, open-label, single-arm study, 36 KTRs were enrolled; 3 were excluded. Patients were evaluated for glucose metabolism and cardiovascular risk factors at baseline, 3, and 6 months after conversion of medication. Serial changes were analyzed by repeated analysis of variance.

RESULTS

The mean duration from transplantation was 12.6 ± 4.0 years and baseline serum creatinine levels were 1.10 ± .23 mg/dL. After conversion, fasting plasma glucose levels increased sequentially from 101.7 ± 18.5 to 107.4 ± 21.3 mg/dL (P = .007), and glycated hemoglobin levels increased from 5.7 ± .8 to 6.0 ± 1.2% (P = .016). Among cardiovascular risk factors, fibrinogen levels were decreased (P = .015), but other factors, including blood pressure and lipid profile, did not change (all P > .05). There was no change in renal function, including serum creatinine (P = .611) and urine protein-to-creatinine ratio (P = .092). Body mass index levels were decreased (P = .037) and body weight tended to decrease (P = .063).

CONCLUSIONS

Switching immunosuppressant therapy to tacrolimus has an apparent negative effect on glucose metabolism and imparts an unclear advantage on cardiovascular risk profiles for long-term stable KTRs.

Conversion From Cyclosporine to Once-Daily Tacrolimus on 50:1 mg Basis: A Short-Term Pilot Study

OBJECTIVES

In addition to graft dysfunction, renal transplant recipients on cyclosporine may be switched to tacrolimus to reduce its drug-related secondary clinical effects and undesirable cosmetic side effects. However, the dose level of once-daily tacrolimus for these patients has yet to be established. The objective of this prospective study was to confirm the safety of converting stable renal transplant recipients on cyclosporine to once-daily tacrolimus at a 50:1 mg ratio.

MATERIALS AND METHODS

Our study enrolled 17 patients receiving cyclosporine who were observed for 3 months. Graft biopsies did not reveal any acute rejection, and the conversion ratio to once-daily tacrolimus was 50:1 mg. Dose adjustments were made to achieve a target tacrolimus trough concentration of 3 to 5 ng/mL at 2 weeks, and graft biopsies were taken after the 3-month observation period.

RESULTS

Dose adjustment was required in 7 recipients (41.2%) within 3 months of conversion. None of the recipients had acute cellular rejection or C4d deposition, and the mean estimated glomerular filtration rate of 38.7 ± 11.0 mL/min/1.73 m2 at baseline was significantly improved to 42.0 ± 10.0 mL/min/1.73 m2 at month 3.

CONCLUSIONS

Although recipients of renal transplant can be forced to discontinue cyclosporine administration due to undesirable adverse effects, our study showed that a once-daily dose of tacrolimus may be safe when administered at a conversion ratio of 50:1.

Biomarkers for individualized dosage adjustments in immunosuppressive therapy using calcineurin inhibitors after organ transplantation

Calcineurin inhibitors (CNIs), such as cyclosporine A and tacrolimus, are widely used immunosuppressive agents for the prevention of post-transplantation rejection and have improved 1-year graft survival rates by up to 90%. However, CNIs can induce severe reactions, such as acute or chronic allograft nephropathy, hypertension, and neurotoxicity. Because CNIs have varied bioavailabilities, narrow therapeutic ranges, and individual propensities for toxic effects, therapeutic drug monitoring is necessary for all CNIs. Identifying the genetic polymorphisms in drug-metabolizing enzymes will help to determine personalized dosage regimens for CNIs, as CNIs are substrates for CYP3A5 and P-glycoprotein (P-gp, MDR1). CNIs are often concomitantly administered with voriconazole or proton pump inhibitors (PPIs), giving rise to drug interaction problems. Voriconazole and PPIs can increase the blood concentrations of CNIs, and both are primarily metabolized by CYP2C19. Thus, it is expected that interactions between CNIs and voriconazole or PPI would be affected by CYP2C19 and CYP3A5 polymorphisms. CNI-induced acute kidney injury (AKI) is a serious complication of transplantations. Neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (KIM-1) are noninvasive urinary biomarkers that are believed to be highly sensitive to CNI-induced AKI. In this article, we review the adverse events and pharmacokinetics of CNIs and the biomarkers related to CNIs, including CYP3A5, CYP2C19, MDR1, NGAL, and KIM-1. We hope that these data will help to identify the optimal biomarkers for monitoring CNI-based immunosuppressive therapy after organ transplantation.

Adverse Events under Tacrolimus and Cyclosporine in the First 3 Years Post-Renal Transplantation in Children

BACKGROUND

Progress in immunosuppression has reduced acute rejection, graft loss and mortality after renal transplantation. Adverse drug reactions are well described in adults but few data are available in children. Our objectives were to analyse the adverse events reported in the first 3 years post-transplantation in children receiving tacrolimus or cyclosporine-based immunosuppression and compare them with the information of the Summary of Product Characteristics.

METHODS

This retrospective study included all children who underwent a renal transplant at Hospital Robert Debré between 2002 and 2015. Initial immunosuppression was based on induction, calcineurin inhibitor, mycophenolate mofetil and corticosteroids. Adverse events were collected from medical records and coded using the Medical Dictionary for Regulatory Activities and the implications of tacrolimus and cyclosporine analysed. Statistical analyses were performed using SAS 9.4.

RESULTS

One hundred and twenty-five children were included. During the observation period [2.7 years (0.6-4.3)], 105 patients received tacrolimus and 39 received cyclosporine. The incidence rate for gastrointestinal disorders was 0.128 and 0.056 by patient-years of exposure (p < 0.05), under tacrolimus and cyclosporine schedules. For neutropenia, it was 0.064 and 0.014 (p < 0.05). The frequencies of toxic nephropathy and gastrointestinal pain were higher than those in the Summary of Product Characteristics of tacrolimus (> 20%) and cyclosporine (> 10%). Cosmetic events for cyclosporine and neutropenia for tacrolimus were frequently observed (18 and 14.3%, respectively), although uncommon in the Summary of Product Characteristics.

CONCLUSIONS

The exposure-adjusted incidence rate of gastrointestinal disorders and neutropenia was higher in children under the tacrolimus schedule. Our findings contribute to the evaluation of the benefit-risk balance of immunosuppressive therapy following paediatric renal transplantation.

Successful treatment of recurrent immunoglobulin a nephropathy using steroid pulse therapy plus tonsillectomy 10 years after kidney transplantation: a case presentation

Background

Both prevention and treatment of recurrent immunoglobulin A nephropathy (IgAN) in kidney transplant recipients are important since recurrent IgAN seems to affect long-term graft survival. We present here a case of recurrent IgAN that was successfully treated using steroid pulse therapy plus tonsillectomy 10 years after kidney transplantation.

Case presentation

A 46-year-old male was admitted for an episode biopsy with a serum creatinine level of 1.8 mg/dl and proteinuria (0.7 g/day). Histological features showed recurrent IgAN (only focal segmental mesangial proliferation) and severe arteriolar hyalinosis partly associated with calcineurin inhibitor toxicity, with limited interstitial fibrosis and tubular atrophy (5%) (IF/TA) 8 years after transplantation. Sodium restriction and conversion from cyclosporine to tacrolimus successfully reduced his proteinuria to the level of 0.15 g/day. However, 2 years later, his proteinuria increased again (1.0 g/day) and a second episode biopsy showed global mesangial proliferation with glomerular endocapillary and extracapillary proliferation accompanied by progressive IF/TA (20%). The steroid pulse therapy plus tonsillectomy successfully decreased his proteinuria and he achieved clinical remission 3 years after this treatment.

Conclusion

This case, presented with a review of relevant literature, demonstrates the difficulty and importance of the treatment of recurrent IgAN and calcineurin inhibitor arteriolopathy, especially in long-term kidney allograft management.

Tacrolimus Versus Cyclosporine as Primary Immunosuppressant After Renal Transplantation: A Meta-Analysis and Economics Evaluation

Tacrolimus and cyclosporine are the major immunosuppressants for renal transplantation. Several studies have compared these 2 drugs, but the outcomes were not consistent. The aim of this study was to evaluate the efficacy, safety, and pharmacoeconomics of cyclosporine and tacrolimus in the treatment of renal transplantation and provide evidence for the selection of essential drugs. Trials were identified through a computerized literature search of PubMed, EMBASE, Cochrane Controlled Trials Register, Cochrane Renal Group Specialized Register of randomized controlled trials, and Chinese Biomedical database. Two independent reviewers assessed trials for eligibility and quality and then extracted data. Data were extracted for patient and graft mortality, acute rejection, and adverse events. Dichotomous outcomes were reported as relative risk with 95% confidence intervals. A decision tree model was populated with data from a literature review and used to estimate costs and quality-adjusted life years gained and incremental cost-effectiveness. Altogether, 6137 patients from 27 randomized controlled trials were included. The results of our analysis were that tacrolimus reduced the risks after renal transplantation of patient mortality, graft loss, acute rejection, and hypercholesterolemia. Nevertheless, tacrolimus increased the risk of new-onset diabetes. Pharmacoeconomic analysis showed that tacrolimus represented a more cost-effective treatment than does cyclosporine for the prevention of adverse events following renal transplant. Tacrolimus is an effective and safe immunosuppressive agent and it may be more cost-effective than cyclosporine for the primary prevention of graft rejection in renal transplant recipients. However, new-onset diabetes should be closely monitored during the medication period.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Late Conversion of Kidney Transplant Recipients from Ciclosporin to Tacrolimus Improves Graft Function: Results from a Randomized Controlled Trial

Background

Tacrolimus (TAC) to ciclosporin A (CSA) conversion studies in stable kidney transplant recipients have reported varying effects on graft function. Here we study graft function (eGFR) trajectories using linear mixed models, which provide effect estimates on both slope and baseline level of GFR and offer increased statistical power.

Methods

Secondary analysis of a randomized controlled trial of CSA treated kidney transplant recipients with stable graft function assigned to receive 0.1 mg/kg/day TAC (target 5–8 ng/ml) or to continue CSA based immunosuppression (target 70–150 ng/ml) at a 2:1 ratio. Renal graft function was estimated via the MDRD (eGFR_MDRD) and CKD-EPI (eGFR_CKD-EPI) formulas.

Results

Forty-five patients continued CSA and 96 patients were converted to TAC with a median follow up of 24 months. Baseline demographics (except for recipient age) including native kidney disease, transplant characteristics, kidney graft function, medication use and comorbid conditions did not differ between groups. In respect to long-term renal graft function, linear mixed models showed significantly improved eGFR trajectories (eGFR_MDRD: p<0.001, eGFR_CKD-EPI: p<0.001) in the TAC versus CSA group over 24 months of follow up. Estimated eGFR_CKD-EPI group differences between TAC and CSA were −3.49 (p = 0.019) at 3 months, −5.50 (p<0.001) at 12 months, and −4.48 ml/min/1.73m² (p = 0.003) at 24 months of follow up. Baseline eGFR was a significant predictor of eGFR trajectories (eGFR_MDRD: p<0.001, eGFR_CKD-EPI: p<0.001). Significant effects for randomization group were evident despite short-term trough levels in the supratherapeutic range (27% (n = 26) of TAC patients at week one). Median TAC trough levels were within target range at week 4 after conversion.

Conclusion

Conversion of CSA treated kidney transplant recipients with stable graft function to TAC (target 5–8 ng/ml) showed significantly improved long-term eGFR trajectories when compared to CSA maintenance (target 70–150 ng/ml).

Trial Registration

ClinicalTrials.gov NCT00182559 EudraCT identifier: 2004-004209-98

Effect of low-dose tacrolimus with mycophenolate mofetil on renal function following liver transplantation

AIM: To determine whether low-dose tacrolimus (TAC) combined with mycophenolate mofetil (MMF) is a safe approach to decrease the incidence of chronic kidney disease (CKD) in liver transplantation (LT) recipients.

METHODS: We analyzed the medical records of 689 patients who underwent LT between March 1999 and December 2012 in a single Chinese center. Immunosuppression was initiated with a calcineurin inhibitor (TAC or CSA) and prednisone with or without MMF. CKD is defined by the glomerular filtration rate (GFR), estimated by an abbreviated Modification of Diet in Renal Disease formula, < 60 mL/min per 1.73 m² for at least 3 consecutive months after LT. Individuals with TAC trough concentrations ≤ 8 ng/mL at 3 mo after LT were defined as the low-dose group. The incidence of CKD within 5 years was compared between the TAC group and the CSA group, as well as between four subgroups (low-dose and high-dose TAC groups with or without MMF).

RESULTS: No difference regarding the occurrence of pre-LT renal dysfunction or that of post-LT rejection was found between the TAC and CSA groups or between the four subgroups. With a definition of GFR < 60 mL/min per 1.73 m², the overall incidence of CKD was significantly higher in the CSA group than in the TAC group. The incidence of CKD in the low-dose TAC + MMF group (7.7%) was significantly lower than that observed in the low-dose TAC group (15.9%), high-dose TAC group (24.6%) and high-dose TAC + MMF group (18.5%). The cumulative 1-, 3- and 5-year incidence rates of CKD were 12.7%, 14.5% and 16.7%, respectively. The cumulative 5-year survival rates were 61.7% and 82.2% in patients with or without CKD, respectively.

CONCLUSION: In LT patients, the choice of immunosuppressive therapy appears to affect renal function and patient survival.

Calcineurin inhibitor sparing strategies in renal transplantation, part one: Late sparing strategies

Kidney transplantation improves quality of life and reduces the risk of mortality. A majority of the success of kidney transplantation is attributable to the calcineurin inhibitors (CNIs), cyclosporine and tacrolimus, and their ability to reduce acute rejection rates. However, long-term graft survival rates have not improved over time, and although controversial, evidence does suggest a role of chronic CNI toxicity in this failure to improve outcomes. Consequently, there is interest in reducing or removing CNIs from immunosuppressive regimens in an attempt to improve outcomes. Several strategies exist to spare calcineurin inhibitors, including use of agents such as mycophenolate mofetil (MMF), mycophenolate sodium (MPS), sirolimus, everolimus or belatacept to facilitate late calcineurin inhibitor withdrawal, beyond 6 mo post-transplant; or using these agents to plan early withdrawal within 6 mo; or to avoid the CNIs all together using CNI-free regimens. Although numerous reviews have been written on this topic, practice varies significantly between centers. This review organizes the data based on patient characteristics (i.e., the baseline immunosuppressive regimen) as a means to aid the practicing clinician in caring for their patients, by matching up their situation with the relevant literature. The current review, the first in a series of two, examines the potential of immunosuppressive agents to facilitate late CNI withdrawal beyond 6 mo post-transplant, and has demonstrated that the strongest evidence resides with MMF/MPS. MMF or MPS can be successfully introduced/maintained to facilitate late CNI withdrawal and improve renal function in the setting of graft deterioration, albeit with an increased risk of acute rejection and infection. Additional benefits may include improved blood pressure, lipid profile and serum glucose. Sirolimus has less data directly comparing CNI withdrawal to an active CNI-containing regimen, but modest improvement in short-term renal function is possible, with an increased risk of proteinuria, especially in the setting of baseline renal dysfunction and/or proteinuria. Renal outcomes may be improved when sirolimus is used in combination with MMF. Although data with everolimus is less robust, results appear similar to those observed with sirolimus.

Calcineurin inhibitor nephrotoxicity: a review and perspective of the evidence

BACKGROUND

There is no doubt that acute calcineurin inhibitor (CNI) nephrotoxicity exists; however, chronic CNI nephrotoxicity is questionable at best.

METHODS

We reviewed the literature to identify original articles related to the use of CNIs in renal and nonrenal solid organ transplantation in order to examine the available evidence about their chronic nephrotoxicity and contribution to graft failure.

RESULTS

Early clinical experience and animal studies support the evidence of CNI nephrotoxicity. These findings evolved into the dogma that CNI nephrotoxicity is the major cause of late renal allograft failure. However, in transplanted kidneys the specific role of chronic CNI nephrotoxicity has been questioned. The emerging literature clearly highlights the lack of solid evidence for the role of CNIs as the sole and major injurious agents that cause chronic renal dysfunction and subsequent graft failure. Most of the evidence available to date is against complete CNI avoidance, and minimization appears to be a more viable strategy. It is becoming increasingly clear that the typical pathological lesions linked to chronic CNI use are highly nonspecific, and most of the chronic changes that have been attributed to chronic CNI nephrotoxicity are the consequences of previously unrecognized immunologic injuries. One needs to keep in mind that the potential risk of side effects of CNI use should be balanced against the risk of rejection.

CONCLUSIONS

More research should focus on addressing the true causes of chronic graft dysfunction rather than focusing on the overexaggerated contribution of CNIs to late graft loss.

Cellular and physiological mechanisms of new-onset diabetes mellitus after solid organ transplantation

New-onset diabetes after transplantation is recognized as one of the metabolic consequences which may increase the risk of morbidity and mortality after solid organ transplantation. The pathophysiology of new-onset diabetes after transplantation has not been clearly defined and may resemble that of Type 2 diabetes, characterized by predominantly insulin resistance or defective insulin secretion, or both. This review aims to summarize the current state of knowledge regarding the prevalence, consequences, pathogenesis, and management of new-onset diabetes after transplantation, with a major focus on the possible mechanisms involved in the pathogenesis of the disorder. The aetiology of new-onset diabetes after transplantation is multifactorial, with diabetogenic immunosuppressive drugs playing a major role. Multiple cellular and physiologic mechanisms are involved in the process. Selection of an appropriate maintenance immunosuppressive regimen should involve balancing the risk of patient and graft survival vs. the potential for new-onset diabetes after transplantation.

Changes in serial B-type natriuretic peptide level independently predict cardiac allograft rejection

BACKGROUND

Despite positive associations with rejection, the clinical value of B-type natriuretic peptide (BNP) monitoring in heart transplant recipients has not been established. We sought to determine the predictive value of changes in serial BNP level for identifying patients with acute allograft rejection.

METHODS

BNP, hemodynamics and biopsies were obtained for 205 transplant recipients who underwent a total of 4,007 endomyocardial biopsy procedures. Samples analyzed were collected ≥ 180 days post-transplant, without evidence of rejection on the immediately preceding biopsy. Using a repeated-measures multivariate model, we assessed the association of change in BNP with Grade ≥ 3A (2R) rejection. We also determined predictive values of various cut-off thresholds of change in serial BNP levels to predict Grade ≥ 3A rejection.

RESULTS

There were 47 episodes of Grade ≥ 3A rejection among the 1,350 samples analyzed. Median change in serial BNP (ΔBNP) for those with Grade ≥ 3A rejection was 20 pg/ml (IQR -26 to 169 pg/ml) and among those with Grade <3A rejection was -4 pg/ml (IQR -34 to 22 pg/ml, p = 0.003). On multivariate analysis, ΔBNP remained the most potent independent predictor of Grade ≥ 3A rejection (p = 0.001). ΔBNP >100 pg/ml predicted increased risk of Grade ≥ 3A rejection (OR = 5.3, p < 0.001) with high specificity (93.3%) and positive predictive value (13.0%) and excellent negative predictive value (97.3%).

CONCLUSIONS

Change in serial BNP level is an independent predictor of cardiac allograft rejection. With wide availability, rapid turnaround, low cost, favorable positive predictive value and excellent negative predictive value, serial BNP monitoring has several advantages for non-invasive monitoring of heart transplant recipients for acute cardiac allograft rejection.

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.

Quantitative proteomic analysis of cyclosporine-induced toxicity in a human kidney cell line and comparison with tacrolimus

The calcineurin-inhibitors (CNIs) cyclosporine (CsA) and tacrolimus (TAC) remain the pillars of modern immunosuppression regimens used in solid organ transplantation. Nephrotoxicity is an adverse effect that limits their successful use. The precise molecular mechanisms underlying this nephrotoxicity remain unclear. Using SILAC together with LC-MALDI-TOF/TOF, we investigated the CNIs-induced proteomic perturbations in renal cells. Among the 495 proteins quantifiable in both forward and reverse SILAC, 69 displayed CsA-induced perturbations: proteins involved in ER-stress/protein folding, apoptosis, metabolism/transport or cytoskeleton pathways were up-regulated, while cyclophilin B as well as nuclear and RNA-processing proteins were down-regulated. Co-administration of CsA with the antioxidant N-acetylcysteine significantly decreased lipid peroxidation and also partially corrected the CsA-induced unfolded protein response. TAC toxicity profile was apparently different from that of CsA, especially without perturbation of cyclophilins A and B, up-regulation of ER-chaperones nor down-regulation of a number of nuclear proteins. These results provide a new insight and are consistent with recent data regarding the molecular mechanisms of CNIs-induced nephrotoxicity. Our findings offer new directions for future research aiming to identify specific biomarkers of CsA nephrotoxicity.

Cardiovascular diseases after kidney transplantation in Korea

Cardiovascular disease (CVD) is the leading cause of death in renal allograft recipients with functioning graft. Our study aimed to determine the incidence and the risk factors of cardiovascular disease after renal transplantation in Korea. We retrospectively analyzed 430 adult recipients who underwent kidney transplantation between January 1997 and February 2007. CVD was defined as a composite outcome of ischemic heart disease, cerebrovascular accident and peripheral vascular disease. Mean age of recipients was 40.0±11.8 yr. Mean duration of follow-up was 72±39 months. The cumulative incidence of CVD after renal transplantation was 2.4% at 5 yr, 5.4% at 10 yr and 11.4% at 12 yr. Multivariate analysis revealed that recipient's age, diabetes mellitus and duration of dialysis before transplantation were associated with post-transplant CVD (hazard ratio 1.843 [95% CI, 1.005-3.381], 3.846 [95% CI, 1.025-14.432] and 3.394 [95% CI, 1.728-6.665] respectively). In conclusion, old age, duration of dialysis and diabetes mellitus are important risk factors for post-transplant CVD, although the incidence of post-renal transplant CVD is lower in Korea than that in western countries.

Treatment strategies to minimize or prevent chronic allograft dysfunction in pediatric renal transplant recipients: an overview

Long-term allograft survival poses a major problem in pediatric renal transplantation, with allograft nephropathy being the principal cause of graft failure after the first post-transplant year. The mechanisms of nephron loss resulting in graft dysfunction are multiple, comprising both immunologic factors such as acute and chronic antibody- or T-cell-mediated rejection and non-immunologic components. The latter include peri-transplant injuries and renovascular lesions (renal artery stenosis, thrombosis) as well as cardiovascular risk factors such as arterial hypertension and hyperlipidemia. Another relevant issue leading to progressive nephron loss and declining kidney transplant function is acute and chronic nephrotoxicity induced by the calcineurin inhibitors (CNIs) ciclosporin (cyclosporine microemulsion) and tacrolimus. Furthermore, the presence of an abnormal lower urinary tract as well as bacterial (recurrent pyelonephritis) and viral (cytomegalovirus [CMV], polyomavirus [BK virus; BKV]) infections are crucial factors involved in the incidence of chronic allograft dysfunction and graft failure. Renovascular lesions and lower urinary tract obstruction are typical indicators for surgical intervention. The aim of treatment in pediatric patients with renal failure secondary to a dysfunctional lower urinary tract is to create a sterile, continent, and nonrefluxive reservoir. Surgical techniques such as bladder augmentation and the introduction of intermittent catheterization and anticholinergic therapy have significantly improved graft outcome. Arterial hypertension, another factor responsible for graft function deterioration in pediatric renal transplant recipients, is controlled preferably by the use of angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists, which are known to possess nephroprotective properties in addition to their potent antihypertensive effects. Although treatment of subclinical rejection with augmented immunosuppression has been associated with better graft survival, an increase of the immunosuppressive level to avoid subclinical rejection should be weighed against the risk of infection. The majority of viral infections affecting kidney allografts are caused by CMV and BKV. Antiviral CMV prophylaxis or pre-emptive therapy with ganciclovir has been shown to have beneficial effects in the pediatric renal transplant population. Treatment of BKV-induced nephropathy is based on reduction of the immunosuppressant therapy, although specific antiviral agents such as cidofovir and leflunomide are known to inhibit BKV. However, cidofovir itself is nephrotoxic and should therefore be administered cautiously to pediatric renal transplant patients. Since CNIs are likewise known for their nephrotoxic effects, especially with long-term use, alteration of the immunosuppressant regimen is necessary in case of deteriorating graft function due to CNI-induced histopathologic changes. Complete CNI avoidance seems inappropriate because, in this situation in pediatric renal transplant recipients, other relatively potent immunosuppressant agents such as lymphocyte-depleting antibodies, which are frequently accompanied by a higher incidence of infections, are needed for rejection prophylaxis. CNI withdrawal and switching of the immunosuppressant regimen from CNI therapy to sirolimus may be an option for some pediatric renal transplant patients with less advanced graft function deterioration. Nevertheless, potential adverse events such as aggravation of proteinuria, hyperlipidemia, myelosuppression, and hypergonadotropic hypogonadism have to be considered, and controlled studies are lacking. At present, an immunosuppressant maintenance therapy composed of low-dose tacrolimus or ciclosporin (CNI minimization) and mycophenolate mofetil with low-dose corticosteroids appears to be the most promising strategy to adopt in pediatric renal transplant recipients at low or normal immunologic risk.

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.

KDIGO clinical practice guideline for the care of kidney transplant recipients

The 2009 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline on the monitoring, management, and treatment of kidney transplant recipients is intended to assist the practitioner caring for adults and children after kidney transplantation. The guideline development process followed an evidence-based approach, and management recommendations are based on systematic reviews of relevant treatment trials. Critical appraisal of the quality of the evidence and the strength of recommendations followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach. The guideline makes recommendations for immunosuppression, graft monitoring, as well as prevention and treatment of infection, cardiovascular disease, malignancy, and other complications that are common in kidney transplant recipients, including hematological and bone disorders. Limitations of the evidence, especially on the lack of definitive clinical outcome trials, are discussed and suggestions are provided for future research.

Renal function and cardiovascular risk profile after conversion from ciclosporin to tacrolimus: prospective study in 80 liver transplant recipients

BACKGROUND

Increased risk of cardiovascular and cerebrovascular disease in liver transplant recipients results in particular from the side effects of calcineurin inhibitor-based immunosuppressive therapy. Several studies have demonstrated a more favourable outcome for patients receiving tacrolimus (TAC) as compared with ciclosporin (CS).

AIM

To investigate the effects of conversion from CS to TAC on cardiovascular risk factors and renal function in liver transplant recipients.

METHODS

In a prospective study, all except two patients had chronic kidney disease stages 2-4 (n = 80), according to estimated glomerular filtration rate using the abbreviated Modification of Diet in Renal Disease equation.

RESULTS

Conversion was accompanied with a mean decrease of total cholesterol from 194.6 +/- 54.0 mg/dL to 175.8 +/- 44.2 mg/dL (P < 0.001), low density lipoprotein cholesterol from 106.7 +/- 39.2 mg/dL to 90.9 +/- 28.6 mg/dL (P < 0.001) and mean arterial blood pressure values from 102.2 +/- 13.2 mm Hg to 95.9 +/- 11.7 mm Hg (P < 0.001). Renal function remained stable. No cases of de novo diabetes mellitus were identified. The Framingham risk score was significantly reduced from 5.2 +/- 4.4 at baseline to 4.4 +/- 5.3 after 12 months (P = 0.006).

CONCLUSIONS

Conversion from CS to TAC has been shown to improve the cardiovascular risk profile and may retard further decline of renal function after liver transplantation.

Dyslipidemia following kidney transplantation: diagnosis and treatment

Lipid abnormalities are a common complication of kidney transplantation, occurring in up to 60% of patients. In fact, impairment of lipid metabolism is often present before renal transplantation due to the uremic state. After transplantation and recovery of renal function, lipid disturbances usually persist but show a different profile due to the various effects of immunosuppressive drugs on lipid metabolism. Actually, steroids, calcineurin inhibitors, and mammalian target of rapamycin inhibitors usually lead to quantitative and qualitative abnormalities of very low-density, low-density, and high-density lipoproteins. As cardiovascular diseases remain the leading cause of death in renal transplant recipients, management of dyslipidemia and other traditional risk factors, such as smoking, arterial hypertension, diabetes mellitus, and obesity, is of great importance to prevent cardiovascular complications and chronic allograft dysfunction. This review addresses the causes of dyslipidemia, the role of immunosuppressive drugs, and current recommendations to manage lipid disorders in renal transplant recipients.

Calcineurin inhibitor nephrotoxicity

The use of the calcineurin inhibitors cyclosporine and tacrolimus led to major advances in the field of transplantation, with excellent short-term outcome. However, the chronic nephrotoxicity of these drugs is the Achilles' heel of current immunosuppressive regimens. In this review, the authors summarize the clinical features and histologic appearance of both acute and chronic calcineurin inhibitor nephrotoxicity in renal and nonrenal transplantation, together with the pitfalls in its diagnosis. The authors also review the available literature on the physiologic and molecular mechanisms underlying acute and chronic calcineurin inhibitor nephrotoxicity, and demonstrate that its development is related to both reversible alterations and irreversible damage to all compartments of the kidneys, including glomeruli, arterioles, and tubulo-interstitium. The main question--whether nephrotoxicity is secondary to the actions of cyclosporine and tacrolimus on the calcineurin-NFAT pathway--remains largely unanswered. The authors critically review the current evidence relating systemic blood levels of cyclosporine and tacrolimus to calcineurin inhibitor nephrotoxicity, and summarize the data suggesting that local exposure to cyclosporine or tacrolimus could be more important than systemic exposure. Finally, other local susceptibility factors for calcineurin inhibitor nephrotoxicity are reviewed, including variability in P-glycoprotein and CYP3A4/5 expression or activity, older kidney age, salt depletion, the use of nonsteroidal anti-inflammatory drugs, and genetic polymorphisms in genes like TGF-beta and ACE. Better insight into the mechanisms underlying calcineurin inhibitor nephrotoxicity might pave the way toward more targeted therapy or prevention of calcineurin inhibitor nephrotoxicity.

Five-year study of tacrolimus as secondary intervention versus continuation of cyclosporine in renal transplant patients at risk for chronic renal allograft failure

BACKGROUND

Chronic allograft nephropathy is the most frequent cause of long-term kidney allograft loss. Studies are desperately needed to improve long-term survival. Tacrolimus has been associated with less rejection and better kidney function compared with cyclosporine in clinical trials. This study tested the hypothesis that conversion from cyclosporine to tacrolimus might improve long-term outcomes in patients with chronic allograft damage.

METHODS

In this multicenter Canadian clinical trial, cyclosporine-treated patients with biopsy-proven chronic allograft nephropathy and impaired renal function were randomly assigned (2:1) to convert to tacrolimus or continue on cyclosporine therapy. A total of 106 (70 tacrolimus and 36 cyclosporine treated) patients were followed-up for up to 5 years. The primary outcome was graft survival.

RESULTS

In an intention to treat analysis, subsequent graft (73% vs. 81%, P=0.2835, log-rank test) and patient survival (91% vs. 92%, P=0.8668, log-rank test) were not different between the tacrolimus and cyclosporine groups, respectively. Changes in Chronic Allograft Damage Index scores on protocol biopsies from baseline to 3 years were not different (+0.4+/-1.8 vs. +1.3+/-3.2, P=0.5910, cyclosporine vs. tacrolimus, respectively). There were no significant differences in biopsy-proven acute rejection (6 [8.6%] vs. 2 [5.6%], tacrolimus vs. cyclosporine, respectively, P=0.5906).

CONCLUSIONS

In this study, patients with chronic allograft damage converted from cyclosporine to tacrolimus demonstrated no apparent benefit.