西罗莫司替代钙调磷酸酶抑制剂方案治疗肾移植后“爬行肌酐”患者的疗效观察（附28例报告）

目的探讨采用西罗莫司替代钙调磷酸酶抑制剂（CNI）方案治疗肾移植后＂爬行肌酐＂患者的临床疗效。方法具有＂爬行肌酐＂表现的28例患者中,术后采用以环孢素（CsA）为主的三联免疫抑制方案20例,采用以他克莫司（FK506）为主的三联免疫抑制方案8例。患者确诊后即停用CsA或FK506,24h后给予西罗莫司,初始剂量6mg,维持剂量为2mg/d,以后根据西罗莫司的血药浓度来调整剂量,使其血药谷浓度维持在5～9μg/L,药物替代前后麦考酚吗乙酯（MMF）及肾上腺皮质激素（激素）的用量不变。随访6个月,定期观察移植物肾功能,记录排斥反应的发生情况,并监测血常规、血糖、血脂、肝功能等指标。结果移植物肾功能明显改善16例,患者的血清肌酐（Scr）由替代前（205±20）μmo1/L降为替代后的（153±18）μmo1/L,内生肌酐清除率（Ccr）由（51±3）ml/min升高为（56±3）ml/min（均为P〈0.05）;移植物肾功能维持稳定8例,移植物肾功能继续恶化2例。治疗中,1例发生急性排斥反应,移植肾失功并恢复血液透析,1例西罗莫司替代后出现明显骨髓抑制而放弃替代治疗,恢复替代前的免疫抑制方案。结论西罗莫司替代CNI治疗肾移植后＂爬行肌酐＂患者是一种比较安全并有效的方法,可明显改善移植物肾功能,但会使患者血脂升高。     

Kidney transplantation with sirolimus and mycophenolate mofetil-based immunosuppression: 5-year results of a randomized prospective trial compared to calcineurin inhibitor drugs

BACKGROUND: We report the 5-year outcomes from a randomized prospective trial in primary adult renal allograft recipients, designed to evaluate calcineurin inhibitor (CNI)-free immunosuppression on kidney transplant function. METHODS: Sixty-one patients were randomized to either sirolimus (n=31) or cyclosporine (n=30) after basiliximab induction and mycophenolate mofetil (MMF) with steroids. Sirolimus was concentration controlled at 10-12 ng/mL for at least 6 months. RESULTS: After 5 years, sirolimus-MMF-steroids compared to cyclosporine-MMF-steroids provides similar patient survival (87.1 vs. 90%, P=0.681), acute rejection rates (12.9 vs. 23.3%, P=0.22), total cholesterol (209.1 vs. 204.3 mg/dL, P=0.973), urine protein/creatinine ratios (0.398 vs. 0.478 mg/dL, P=0.72), and overall medical and surgical morbidity (P=NS). Although unadjusted patient survival was similar, sirolimus based CNI-free patients had longer death censored graft survival (96.4 vs. 76.7%, P=0.0265), higher glomerular filtration rate (GFR) by the abbreviated Modified Diet in Renal Disease (66.7 vs. 50.7 cc/min, P=0.0075), and fewer graft losses from chronic allograft nephropathy. The Banff chronic scores at two years were strong predictors of 5-year GFR. At 5 years, there were six de novo (three solid organ, three skin) cancers in the CNI group and only two de novo (one skin, one leukemia, no solid organ) cancers in the sirolimus group (P=NS). CONCLUSIONS: This study of low to moderate risk patients demonstrates that excellent 5-year kidney transplant outcomes can be achieved without CNI drugs, when therapeutic drug monitoring of sirolimus is employed. The application of CNI drug avoidance protocols to high-risk recipients (retransplants, highly sensitized, etc.), extrarenal allograft recipients, or alternative drug regimens such as steroid or MMF elimination should be subjected to controlled trials.     

Sirolimus and mycophenolate mofetil as calcineurin inhibitor-free immunosuppression in a cardiac transplant patient with chronic renal failure.

Chronic renal failure triggered by calcineurin inhibitor (CNI)-based immunosuppression is a common complication after cardiac transplantation. Sirolimus and mycophenolate mofetil (MMF) are 2 newer immunosuppressive agents with no documented nephrotoxic side effects. This case report describes a patient with ongoing chronic renal failure 10 months after cardiac transplantation on cyclosporine-based immunosuppressive therapy. Conversion of the immunosuppressive regimen from cyclosporine to sirolimus and MMF resulted in freedom from acute rejection, excellent cardiac graft function and consistently improved renal function. This case illustrates the beneficial potential of sirolimus and MMF as CNI-free and safe long-term immunosuppression in a patient with chronic renal failure after heart transplantation.     

Proteinuria Developing After Clinical Islet Transplantation Resolves with Sirolimus Withdrawal and Increased Tacrolimus Dosing

Sirolimus is a potent immunosuppressant, which may permit the avoidance of nephrotoxic calcineurin inhibitors (CNI). However, cases of proteinuria associated with sirolimus have been reported following renal transplantation. Here, we report three cases of proteinuria (1, 2 and 7 g/day) developing during therapy with sirolimus plus low-dose tacrolimus following clinical islet transplantation (CIT) in type I diabetic subjects. The proteinuria resolved after discontinuation of sirolimus, substituted by mycophenolate mofetil (MMF) combined with an increased dose of tacrolimus. A renal biopsy in one case indicated only the presence of diabetic glomerulopathy. Five other CIT recipients developed microalbuminuria while on sirolimus which all resolved after switching to tacrolimus and MMF. The resolution of proteinuria from the native kidneys of CIT recipients after the discontinuation sirolimus suggests that, at least in some individuals, sirolimus itself may have adverse renal effects. Sirolimus should be used cautiously with close monitoring for proteinuria or renal dysfunction.     

肝移植后因药物不良反应暂停及转换钙调磷酸酶抑制剂的单中心经验

目的 研究肝移植术后暂停及转换钙调磷酸酶抑制剂(CNI)对控制感染和改善受损肾功能的作用.方法 回顾性分析单中心施行的947例原位肝移植的资料,分为2个阶段,第1阶段(2002年1月至2007年12月)有234例肝移植术后发生感染的患者,第2阶段(2008年1月至2010年12月)有101例.2个阶段共有329例受者因CNI肾毒性而造成肾功能损害,其中将CNI转换为SRL者40例(转换组),其余289例采取CNI减量+吗替麦考酚酯(MMF)加量方案(减量组).结果 肝移植术后存活超过1、3和5年者CNI的应用率分别为95.8%、95.3%和97.5%.第2阶段共有17例受者短期停用免疫抑制剂,停药的主要原因是细菌(部分合并真菌)感染(88.2%);2个阶段共有48例患者将CNI转换为SRL,换药主要原因是肾功能损害(83.3%).第2阶段感染患者中短期暂停CNI者15例,占14.9%(15/101),CNI暂停后感染控制的有效率为73.3%(11/15),排斥反应发生率为6.7%(1/15).第2阶段感染患者的累积存活率明显高于第1阶段(P＜0.05).转换组CNI转换前肾小球滤过率为(0.82±0.24)ml/s,CNI转换后6周时为(1.28±0.31)ml/s,6个月时为(1.36±0.32)ml/s,转换后6周和6个月时高于转换前(P＜0.05).CNI调整后6个月时,转换组患者存活率为85.0%,减量组为83.7%(P＞0.05).结论 肝移植术后患者发生感染及肾功能损害时可采取CNI减量甚至短时间停用CNI,或转换使用SRL,此方案是安全、有效的.

Abstract：

Objective To report the results of a single-center, retrospective study on the effect of calcineurin inhibitors (CNI) withdraw for controlling infections and conversion to sirolimus (SRL)for ameliorating renal dysfunction. Methods A total of 947 liver transplant cases from 2002 to 2010were divided into two eras (Jan. 2002 to Dec. 2007 and Jan. 2008 to Dec. 2010). There were 234cases of infections after liver transplantation (LT) in the first era and 101 cases in the second era. And of 329 cases of CNI-related renal dysfunction after LT in two eras, 40 cases (converting group) had converted CNI to SRL, while 289 cases (reducing group) adopted protocol of CNI reducing and mycophenolate mofetil (MMF) raising. Results CNI-based IS took up 95.8 %, 95. 3 %, 97. 5 % of the IS protocols with recipient survival time longer than 1, 3, and 5 years. The primary cause for CNI withdraw was infection (88. 2 %, 15/17) in the second era, and renal dysfunction for conversion to SRL in the two eras (83. 3 %, 40/48). In the second era, 14. 9% (15/101) of the cases of infections after LT experienced CNI withdraw. Of the 15 patients, 11 had effectively controlled the infection (77. 3 %) while rejection rate was 6. 7 % (1/15). The cumulative survival rate of the second era was significantly higher than the first era (P＜0. 05). The glomerular filtration rate (GFR) of converting group at 6th week and 6th month was statistically elevated as compared with that before conversion,respectively (1.28 ± 0. 31, 1.36 ± 0. 32 mL/s vs. 0. 82 ± 0. 24 mL/s, P＜0. 05). Six months after CNI adjustments, survival rate of converting group and reducing group was 85. 0% and 83. 7 %,respectively (P＞0. 05). Conclusion Reducing or even short-term withdraw of CNI may allow the better control of infections after LT, and the conversion from CNI to SRL can ameliorate the CNIrelated nephrotoxicity. These individually tailored IS protocols will benefit the long term survival for LT.     

Calcineurin inhibitor substitution with sirolimus vs. reduced-dose calcineurin inhibitor plus sirolimus is associated with improved renal dysfunction in heart transplant patients

Heart transplant (HTx) patients are at risk of developing renal dysfunction. Sirolimus has been used as an alternative for calcineurin inhibitors (CNI) in transplant patients with renal dysfunction. Recent data suggest that the combination of sirolimus with a CNI is associated with a deterioration of renal function in renal transplant patients. The purpose of the present study was to compare the effect on the creatinine clearance (CrCl) of heart transplant (HTx) patients with renal dysfunction (RD) on CNI-based sirolimus-free regimens of conversion to either reduced-dose CNI plus sirolimus or outright substitution of CNI with sirolimus. We retrospectively identified 29 treatment switches for 26 patients with RD defined as a decline in the CrCl > 25% post-HTx. Treatment switches were divided into two groups. Group 1 included 13 switches in 13 patients (four women, nine men, age 62 +/- 10 yr) in whom sirolimus replaced CNI. Group 2 included 16 switches in 15 patients [two women, 13 men (one man underwent two such switches), age 61 +/- 9 yr] in whom CNI dose was reduced and sirolimus was added. Two men appear in both groups. Average follow-up was 10.4 +/- 3.2 months. Overall mortality, rejection, and side-effects rates were comparable between groups. At 12-months post-switch, the mean CrCl had increased from 48 +/- 15 at time of treatment switch to 56 +/- 22 mL/min in group 1 and decreased from 53 +/- 19 to 47 +/- 17 mL/min in group 2 (p = 0.02). In conclusion, substitution of CNI with sirolimus provided improved renal recovery compared with lower-dose CNI plus sirolimus in HTx patients with renal dysfunction.     

Long-term effects on renal function of dose-reduced calcineurin inhibitor and sirolimus in cardiac transplant patients

Calcineurin inhibitor (CNI)-associated renal insufficiency is common after cardiac transplantation (CTX); however, the addition of sirolimus allows for CNI dose reduction and this strategy may limit CNI renal toxicity. This study examines the long-term effects of such a strategy. METHODS: Patients from a single center who had CTX from 1990 to 2007 and who were converted to sirolimus and a dose-reduced CNI were compared to group-matched controls maintained on CNI and an antiproliferative agent. RESULTS: One hundred and fifty-five patients (79 sirolimus and 76 controls) were included and had similar baseline characteristics. Sirolimus was started a mean of 1429 d post-CTX and maintained for a mean of 823 d. Reason for conversion to sirolimus was renal insufficiency (34%), vasculopathy (29%), recurrent rejection (19%), and other (18%). The eGFR was not different between groups at baseline (44.7 mL/min/1.73 m(2) vs. 46.0, p = 0.64) or at any point during follow-up: 90 d, 180 d, 1 yr, 2 yr, and 3 yr. conclusion: Patients converted to a regimen of sirolimus and a dosed-reduced CNI have stable renal function over the following three yr, but do not have an improvement in renal outcomes compared to patients maintained on full dose CNI.     

Calcineurin-inhibitor-sparing immunosuppressive protocols

Calcineurin inhibitors (CNI) have played an important role in improving graft survival. However, the balance between preventing immunologic allograft losses and the management of CNI-related nephrotoxicity is still an issue in renal transplantation. There are three major CNI-sparing strategies. CNI MINIMIZATION: The advent of mycophenolate mofetil (MMF) allows cyclosporine (CsA) reduction to ameliorate renal function in patients with chronic renal allograft dysfunction, without increasing acute rejection rates. In combination with mTOR inhibitors, very low CNI levels may be sufficient to prevent acute rejection. However, in this association, CNI nephrotoxicity is magnified by pharmacokinetic interaction. CNI WITHDRAWAL: CNI withdrawal has been attempted in regimens containing MMF or sirolimus (SRL). Introduction of MMF in patients with chronic allograft nephropathy (CAN) followed by CNI withdrawal resulted in stabilization or improvement of renal function and hypertension profile, although there is some risk of acute rejection. In regimes based on SRL, CNI withdrawal is a safety strategy, achieving a sustained improvement of renal function, histology, and graft survival. There is not consensus at all whether MMF should be added or not in patients converted from CNI to mTOR inhibitor. CNI AVOIDANCE: Polyclonal-based regimens with MMF and steroids have shown acceptable acute rejection rates, but high rates of cytomegalovirus (CMV) and opportunistic infections. Conversely, anti-IL-2R in combination with MMF and steroids resulted in 50% incidence of acute rejection, thus suggesting that CNI avoidance is not feasible in a regimen based on MMF. Alternatively, a protocol based on anti-IL-2R induction therapy combined with SRL, MMF, and prednisone has shown an efficient prevention of acute rejection, higher creatinine clearance and lower rate of CAN in comparison with a group treated with CNI. New strategies using costimulation blockade may help in the development of safe CNI-free regimens. In summary, in renal transplantation the new immunosuppressive medications have made feasible old aspirations such as minimization, withdrawal, or even avoidance of CNI.     

Is sirolimus a safe alternative to reduce or eliminate calcineurin inhibitors in chronic allograft nephropathy in kidney transplantation?

PURPOSE: We evaluate whether cyclosporine (CsA) or tacrolimus (FK) could be reduced or eliminated after sirolimus was added in chronic allograft nephropathy (CAN). By reducing doses of CsA or FK, we expected that renal function would improve. METHOD AND MATERIAL: Twenty-one patients with CAN had sirolimus added as an immunosuppressive agent. We evaluated the creatinine (Cr) level 3 months after addition. The doses of CsA and FK were decreased gradually and then eliminated over a course of 4 to 6 weeks. If the Cr level rose rapidly or other prominent signs of rejection occurred; low-dose CsA or FK would be added per protocol. We evaluated the duration of engraftment before sirolimus and the Cr level when it was added. RESULTS: Renal function improved in 13 of 21 cases. The improvement in Cr ranged from 12.5% maximally to 1.84% minimally. Seven of 13 cases still required low-dose CsA. The average duration of engraftment before sirolimus was 13.66 +/- 10.80 months. The average Cr level before sirolimus was 1.65 +/- 0.56 mg/dL. In the other eight cases, the Cr level kept rising from 5.1% to 20.4%. The average duration of engraftment was 88.38 +/- 42.21 months. The average Cr level before sirolimus was 2.85 +/- 0.54 mg/dL. Hyperuricemia was noted in 31.3% and hyperlipidemia in 68.8%. CONCLUSION: Sirolimus is a safe alternative to reduce or eliminate CsA or FK in CAN. In cases with a long duration of engraftment and high Cr level, sirolimus might have some effect as a substitute for CNI and thus prevent further nephrotoxicity.     

Mycophenolate mofetil-based immunosuppression with sirolimus in renal transplantation: a randomized, controlled Spare-the-Nephron trial

As part of the Spare-the-Nephron trial, we evaluated the combination mycophenolate mofetil (MMF) and sirolimus (SRL) as a calcineurin inhibitor (CNI)-free regimen for the preservation of renal function in renal allograft recipients. This 2-year, open-label, multicenter trial randomized 299 patients of which 151 were maintained on MMF and a CNI, 148 on MMF plus SRL (n=120, tacrolimus; n=31, cyclosporine). Baseline characteristics including measured (iothalamate) glomerular filtration rate (GFR) were similar between groups. After 1 year, the mean percentage change from baseline in the primary end point of measured GFR was significantly higher in the MMF/SRL group compared with the MMF/CNI group. After 2 years, the change was indistinguishable. Calculated creatinine clearance and GFR were significantly greater with MMF/SRL at 2 years within which biopsy-proven acute rejection (BPAR) occurred in 14 MMF/SRL-treated patients (3 graft losses) and in 17 receiving the MMF/CNI (6 graft losses). Significantly, no patients receiving MMF/SRL but five treated with MMF/CNI died. Thus, compared with MMF/CNI treatment, a 2-year regimen of MMF/SRL resulted in similar measures of renal function but with fewer deaths and a trend to less BPAR and graft loss.     

Initial experience with sirolimus and mycophenolate mofetil for renal rescue from cyclosporine nephrotoxicity after heart transplantation

Calcineurin inhibitors (CNIs) have become the cornerstone of immunosuppressive regimens following heart transplantation, but their use is associated with nephrotoxicity. We evaluated a CNI elimination protocol in 14 patients with renal impairment at 48.3 +/- 36.0 months after heart transplantation. The mean serum creatinine was 321 +/- 107 micromol/L; cyclosporine (n=13) or tacrolimus (n=1) was discontinued with sirolimus commenced immediately, initially aiming for a target trough level of 16 (12 to 20) ng/mL. If patients were not receiving mycophenolate (MMF) this was initiated at 1 g bid. The transfer period was covered with a tapering course of corticosteroids. In addition to monitoring clinical status, hematology, biochemistry, and sirolimus levels, graft function was assessed by echocardiography, ECG, and, where indicated, endomyocardial biopsy. Renal function improved in 12 patients (with 6 having a greater than 40% decrease in serum creatinine), remained unchanged in 1, and deteriorated in 1. Two patients who were converted at 15 and 139 months after transplantation experienced grade 3A rejection. One patient experienced a fall in ejection fraction without histologic evidence of rejection. Sirolimus was discontinued in three patients because of side effects: bone marrow suppression, presumed lymphocytic pneumonitis, and generalized acneform rash complicated by an axillary abcess; 50% of patients continue on sirolimus. In conclusion, withdrawal of CNIs after heart transplantation resulted in an improvement in renal function in most patients: 43% experienced a substantial improvement. CNI elimination protocols need to be refined to reduce the risk of breakthrough rejection and to minimize side effects while protecting renal function after heart transplantation.     

Conversion to sirolimus-based immunosuppression in maintenance liver transplantation patients.

Sirolimus (SRL) has been proposed to replace calcineurin inhibitors (CNI) in case of CNI-induced toxicity. The aim of this study was to evaluate the efficacy and safety of conversion from CNI to SRL in maintenance liver transplantation (LT) patients. Between 2002 and 2006, conversion was performed in 48 patients (17 female, 31 male; mean age 57 +/- 10 yr) after a median delay of 19.4 months (range 0.2-173 months) after LT. Indication for conversion was renal impairment (RI) (78%), CNI neurotoxicity (13%), or post-LT cancer (9%). Median follow-up was 22.6 +/- 11 months. Median SRL dosage and trough levels were 2.4 +/- 1.3 mg and 8.1 +/- 2.7 microg/L. Immunosuppression consisted of SRL alone (33%), or SRL + mycophenolate mofetil (MMF) (39%), SRL + prednisone (15%), SRL + CNI (4%), or SRL + MMF + prednisone (8%). Mean glomerular filtration rate (GFR) improved from 33 to 48 mL/minute in patients with severe RI (P = 0.022) and from 56 to 74 mL/minute in patients with moderate RI (P = 0.0001). After conversion, main complications were albuminuria (36%), hyperlipidemia (49%), dermatitis (14%), edema (14%), oral ulcers (12%), joint pain (4%), infection (2%), and pneumonia (2%). Acute rejection (AR) occurred in 17% of the patients. SRL was withdrawn in 17% of the patients. In conclusion, conversion from CNI to SRL is safe and is associated with significant renal function improvement.     

Recovery of Renal Function in Heart Transplantation Patients After Conversion From a Calcineurin Inhibitor-Based Therapy to Sirolimus

Background

Renal failure is the most important comorbidity in patients with heart transplantation, it is associated with increased mortality. The major cause of renal dysfunction is the toxic effects of calcineurin inhibitors (CNI). Sirolimus, a proliferation signal inhibitor, is an imunossupressant recently introduced in cardiac transplantation. Its nonnephrotoxic properties make it an attractive immunosuppressive agent for patients with renal dysfunction. In this study, we evaluated the improvement in renal function after switching the CNI to sirolimus among patients with new-onset kidney dysfunction after heart transplantation.

Methods

The study included orthotopic cardiac transplant (OHT) patients who required discontinuation of CNI due to worsening renal function (creatinine clearance < 50 mL/min). We excluded subjects who had another indication for initiation of sirolimus, that is, rejection, malignancy, or allograft vasculopathy. The patients were followed for 6 months. The creatinine clearance (CrCl) was estimated according to the Cockcroft-Gault equation using the baseline weight and the serum creatinine at the time of introduction of sirolimus and 6 months there after. Nine patients were included, 7 (78%) were males and the overall mean age was 60.1 ± 12.3 years and time since transplantation 8.7 ± 6.1 years. The allograft was beyond 1 year in all patients. There was a significant improvement in the serum creatinine (2.98 ± 0.9 to 1.69 ± 0.5 mg/dL, P = .01) and CrCl (24.9 ± 6.5 to 45.7 ± 17.2 mL/min, P = .005) at 6 months follow-up.

Conclusion

The replacement of CNI by sirolimus for imunosuppressive therapy for patients with renal failure after OHT was associated with a significant improvement in renal function after 6 months.     

Conversion to sirolimus in pediatric renal transplantation recipients

We retrospectively evaluated the efficacy and safety of sirolimus (SRL) in 16 pediatric renal transplant recipients, who were 9.4 +/- 4.1 years of age when they first received SRL. The indications for SRL therapy were rescue from steroid-resistant acute rejection (31.3%), neoplasia (31.3%), diabetes (12.5%), polyomavirus-associated nephropathy (6.3%), chronic allograft dysfunction (6.3%), calcineurin inhibitor nephrotoxicity (6.3%), and hemolytic uremic syndrome (6.3%). Mean follow-up after the switch to SRL was 17.7 +/- 15 months. The final immunosuppression was CNI + SRL + prednisone (PRED) in five patients, SRL + PRED in six, SRL + mycophenolate mofetil (MMF) + PRED in four, and SRL + MMF in one. The use of SRL in these selected pediatric renal recipients was successful, except when creatinine was high at the moment of conversion. Further studies are necessary to assess the beneficial outcomes versus adverse events among the pediatric transplant population receiving SRL for immunosuppression.     

肝移植后并发他克莫司不良反应者的西罗莫司单药转换治疗14例

目的 总结出现钙调磷酸酶抑制剂(CNI)相关并发症的患者采用西罗莫司(SRL)单药转换治疗的体会.方法 肝移植患者14例,其中因CNI类药物致肾功能受损而行转换治疗者13例,因移植后血糖升高而行转换治疗者1例.转换治疗前,患者采用他克莫司(Tac)和糖皮质激素预防排斥反应,部分患者还加用霉酚酸酯.进行转换治疗后,初次给予SRL 4 mg/d;1周内给予SRL 1～2 mg/d,同时Tac的用量减至原来的一半;治疗1周后,根据血SRL浓度调整其剂量,维持血SRL浓度谷值为5～10μg/L,于转换治疗后1～2周完全撤除Tac.观察患者转换治疗后并发症的改善情况,肾功能、肝功能和急性排斥反应的发生情况及药物不良反应等.结果 转换治疗前,13例肾功能受损者的血肌酐为(158.3±41.6)μmol/L,随访结束时降低到(103.7±21.2)μmol/L;另1例血糖升高者在转换治疗后血糖得到有效控制,胰岛素用量由转换前的80 IU/L减少至24 IU/L.转换治疗后6个月内,14例中有2例(14.3%)发生急性排斥反应,治疗后均逆转.随访过程中,4例出现血脂升高,4例出现贫血或血小板减少,5例出现溃疡型口疮,但无患者因SRL不良反应而终止转换治疗.结论 肝移植术后出现CNI相关并发症的患者可以采用SRL单药转换治疗.     

Poor tolerance of sirolimus in a steroid avoidance regimen for renal transplantation

Vascular disease and chronic allograft nephropathy have prompted re-evaluation of steroids and calcineurin inhibitors (CNIs) in renal transplantation. Sirolimus (SRL) can facilitate early CNI withdrawal. We report on the Early CNI and Steroid Elimination in Leeds (ECSEL) study, which was terminated early due to poor tolerability of SRL. Basiliximab/methylprednisolone induction was used, then 2 months of tacrolimus (TAC) and mycophenolate mofetil (MMF) treatment. A total of 51 patients were randomized to continue TAC/MMF or switch to SRL/MMF. In ECSEL1, patients were switched at 2 months (n=10). In ECSEL2, SRL was introduced at months 4-6 and TAC was tapered (n=13). Median overall follow up was 701 days. All 10 ECSEL1 and 10 of 13 (77%) ECSEL2 patients discontinued SRL due to adverse events, including leucopenia, rash, mucosal ulceration, arthralgia, and possible pneumonitis. Mean end-of-study creatinine was comparable in all groups. Sirolimus should be used with caution in complete CNI and steroid withdrawal, due to the resultant intolerable adverse event profile.     

Sirolimus Does Not Exhibit Nephrotoxicity Compared to Cyclosporine in Renal Transplant Recipients

Sirolimus and cyclosporine (CsA) prevent acute rejection in man when used as primary therapies in triple drug regimens. Sirolimus does not act via the calcineurin pathway and therefore is not expected to produce the same renal side-effects. This paper presents the pooled 2-year data analysis of renal function parameters from two open-label, randomized, multicenter studies. Patients (18-68 years) receiving a primary renal allograft were randomized to receive concentration-controlled sirolimus (n = 81) or CsA (n = 80), in combination with azathioprine and steroids (n = 83), or mycophenolate mofetil (MMF) and steroids (n = 78). From week 10 through year 2, calculated glomerular filtration rate (GFR) was significantly higher in sirolimus--than in CsA-treated patients (69.3 vs. 56.8 mL/min, at 2 years, p = 0.004). Serum uric acid was significantly higher in the CsA-treated patients and magnesium was significantly lower; these parameters were more likely to be within normal limits in the sirolimus group. Mean serum potassium and phosphorus were lower in sirolimus-treated patients. In conclusion, sirolimus, when administered as primary therapy in combination with azathioprine or MMF, has a favorable safety profile compared to CsA with regards to renal function.     

Optimizing the clinical utility of sirolimus‐based immunosuppression for kidney transplantation

While calcineurin inhibitors (CNIs) are effective for preventing acute rejection in kidney transplant recipients, long‐term use may cause chronic kidney injury and is associated with increased risks of cardiovascular events, cancer, and infection‐associated death. Immunosuppression strategies are needed to balance risks of acute and subclinical rejection with long‐term benefits of improved kidney function. Sirolimus, an inhibitor of mammalian target of rapamycin, is used for immunosuppression in kidney transplantation. Its clinical utility has evolved, over more than 15 years, including de novo sirolimus with and without concomitant CNIs and conversion from CNI‐based regimens to sirolimus. Sirolimus‐containing regimens are associated with preservation of good renal function, with promising characteristics for improving long‐term graft and patient survival, including antiviral and anticancer effects. Based on clinical evidence, use of low‐dose sirolimus in a de novo approach with tacrolimus/steroids in the immediate posttransplantation period is appropriate. A feasible alternative is a long term, CNI‐free combination with mycophenolate mofetil (following CNI‐to‐sirolimus conversion at 3‐6 months). These strategies are appropriate for a broad range of patients with various levels of immunologic risk, including those receiving expanded criteria donor kidneys or at increased risk of delayed graft function, particular challenges in Latin America and other global regions.     

Conversion from calcineurin inhibitors to sirolimus in kidney transplant patients reduces the urinary transforming growth factor-beta1 concentration

INTRODUCTION: Chronic allograft dysfunction (CAD) is the main cause of late transplant failure. Although several etiologies have been postulated, toxicity for calcineurin inhibitors (CNIs) is one of the most important causes of CAD, characterized by arteriolar hyalinosis, luminal narrowing, increased glomerulosclerosis, and tubulointerstitial damage. It's known that in transplant patients with CAD, fibrogenic mediators such as transforming growth factor beta (TGF-beta) are increased. Sirolimus is an immunosuppressive agent with a distinct mechanism of action compared with CNI. AIM: This study assessed variations in levels of fibrogenic mediators among CAD patients treated with CNIs, before and after conversion to sirolimus. PATIENTS AND METHODS: We studied twelve renal transplant patients with CAD on CNI treatment. TGF-beta in plasma and urine, endothelin-1, and vascular endothelial growth factor (VEGF) were studied before and 8 months after conversion to sirolimus treatment. RESULTS: TGF-beta urine levels decreased from 24.7 +/- 11.2 to 12.8 +/- 5.1 ng/24 h (P = .049). In plasma, a similar decrease trend was observed (22.2 +/- 32 to 10.3 +/- 3 ng/mL), although it was not significant (P = .079). Endothelin-1 showed a decrease (8.1 +/- 3 to 5.2 +/- 1.1 pmol/L; P = .1) and VEGF in plasma increased from 34.3 +/- 37 to 92.2 +/- 86 pg/mL (P = .051). CONCLUSIONS: Patients undergoing conversion from CNI to sirolimus treatment for CAD presented a significant decrease in TGF-beta urine levels, representing a decreased mediator of the CAD fibrogenic process.     

肝移植术后长期存活慢性肾功能损害受者的免疫抑制方案个体化应用

目的探讨肝移植术后长期存活慢性肾功能损害受者应用个体化免疫抑制方案的疗效。方法选择18岁以上、肝移植术后2年以上、入组前采用以他克莫司(FK506)为基础免疫抑制方案、肝功能正常而肾功能损害的受者,共32例。根据免疫功能评分和白细胞计数制定个体化免疫抑制方案,以FK06用量最小化为原则,转换为麦考酚吗乙酯(MMF)或西罗莫司,并调整其用量。调整后至少每个月随访1次,进行肝功能、肾功能、血常规检查和免疫功能评估。结果 32例受者经个体化免疫抑制方案治疗,随访(24.3±7.6)个月,个体化治疗后各时段的肾小球滤过率(GFR)均较此前有明显提高(均为P<0.01),以调整用药后1个月最明显。无发生排斥反应。结论根据免疫功能评分和白细胞计数制定个体化免疫方案,使FK506用量最小化,可以有效改善肝移植术后长期存活的受者的肾功能,并不增加排斥反应的发生率。