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.     

将钙调磷酸酶抑制剂转换为西罗莫司在慢性移植肾肾病中的临床治疗效果

目的 探讨慢性移植肾肾病(CAN)患者将免疫抑制方案中钙调磷酸酶抑制剂(CNI)转换为西罗莫司(SRL)的有效性及安全性.方法 选取72例经移植肾活检证实发生CAN的受者,其中35例将免疫抑制方案中CNI转换为SRL(SRL组),其余37例继续原CNI方案(CNI组).另取10例因其他原因将CNI转换为SRL治疗的受者,将45例转换为SRL的患者分为A组[血肌酐(SCr)＜120 μmol/L),B组(SCr为120～200 μol/L,且Banff分级为Ⅰ～Ⅱ级),C组(SCr为120～200 μmol/L,且Banff分级在Ⅱ级以上),D组(SCr＞200 μmol/L).随访期为24个月,检测各组随访期内的各临床指标.结果 转换治疗前,两组间SCr和肾小球滤过率(eGFR)的差异无统计学意义(P＞0.05);转换治疗后24个月内,SRL组SCr水平和eGFR较CNI组明显改善(P＜0.05),而CNI组的移植肾功能有逐渐衰退的趋势.SRL组尿蛋白及血脂明显上升(P＜0.05),而CNI组变化不大;SRL组血小板计数较CNI组明显下降(P＜0.05),两组间其他指标的差异无统计学意义(P＞0.05).A组患者各指标在转换治疗前后的变化并不大,B组患者的肾功能及蛋白尿有改善明显,C组和D组患者肾功能有不同程度衰退情况,且蛋白尿加重.结论 SRL转换治疗对于稳定及改善CAN患者的移植肾功能是有效、安全的,CAN早期进行转换(SCr＜200 μmol/L)效果明显.     

移植肾功能减退受者使用西罗莫司替代钙调磷酸酶抑制剂的转换治疗

目的研究肾移植术后移植肾功能减退的受者将钙调磷酸酶抑制剂（CNI）转换为西罗莫司（SRL）治疗后的有效性及安全性。方法对45例肾移植术后以CNI为主要免疫抑制剂的移植肾功能减退受者（在过去6个月内血肌酐浓度上升超过20％或达到176-308μmol／L）采用以SRL替换CNI的转换治疗。转换治疗时距离患者肾移植术后6～44个月，平均13．24-月。转换治疗方案采取CNI快速减量并停用，与其联合应用的其他免疫抑制剂在转换期间剂量维持不变，SRL首剂单次口服负荷剂量为4～6mg／d，维持剂量1～2mg／d。随访6个月，观察其临床效果和不良反应。结果SRL的血药浓度维持在4～8μg／L。血清肌酐在转换治疗前为（242．15±73．04）μmol／L，转换治疗后3个月和6个月时分别下降至（188．32±58．96）μmol／L和（173．36±58．08）μmol／L（P〈0．05）。转换治疗后3个月时血尿素氮、血红蛋白和血清钙浓度明显下降，转换治疗后6个月时血清钾和钙浓度明显下降（P〈0．05）。在转换治疗期间所有患者均未发生排斥反应，人、肾存活率100％；有3例患者并发感染，经抗生素治疗后好转。结论肾移植术后发生移植肾功能减退或慢性移植肾肾病的受者，用SRL替换CNI是一种安全有效的治疗方案。     

西罗莫司替代钙调磷酸酶抑制剂治疗肾移植后慢性移植肾肾病

目的 探讨采用西罗莫司（SRL）替换钙调磷酸酶抑制剂（CNI）治疗肾移植术后慢性移植肾肾病（CAN）的有效性和安全性。方法 在42例肾移植术后发生CAN的患者中，有32例采用以环孢素A（CsA）为主的免疫抑制方案；10例采用以他克莫司（FK506）为主的免疫抑制方案。将患者的CsA或FK506替换为SRL，停用CNI 12h后口服SRL，SRL的初始剂量为4mg，然后改为2mg／d，以后根据SRL的血药谷值浓度调整其使用剂量，使其血药谷值浓度维持在5～8μg／L。药物替换前、后霉酚酸酯和激素的用量不变。所有患者均随访1年，观察血肌酐、肌酐清除率的变化并监测血常规、血糖、血脂、肝功能等指标。结果 SRL替换CNI治疗1年后，25例患者的移植肾功能明显改善，替换治疗3～20周后移植肾功能好转；10例患者的移植肾功能维持稳定；但7例患者的肾功能继续恶化。替换治疗后，患者血肌酐从替换前的（218±14）μmol／L降为（187±11）μmol／L，肌酐清除率从替换前的（0．83±0．03）ml／s升高为（0．90±0．03）ml／s，替换前后比较，差异有统计学意义（P〈0．05）。所有患者均未发生急性排斥反应和肿瘤等不良反应。结论 SRL替换CNI治疗慢性移植肾肾病是安全有效的，该方案的副作用主要是血脂增高。     

哪些患者可以从转换西罗莫司中受益?

目的 评价西罗莫司(SRL)替代钙调磷酸酶抑制剂(CNl)类药物的安全性和可行性.方法肾移植术后>3个月,以CNI为基础免疫抑制剂患者157例,按转换SRL的原因分A组(计划性转换,62例)、B组(SCr升高,50例)、C组(高胆红素,37例)和D组(肿瘤,8例),以SRL为基础免疫抑制剂,撤除CNI类药物,观察急性排斥反应和不良事件发生率,随访时间为6个月. 结果 移植肾和患者均存活.发生急性排斥反应2例.SCr和尿酸在转换后1个月开始下降,而肌酐清除率(CCr)开始升高,转换前后尿酸比较差异有统计学意义(P<0.01).A组转换前和转换后1个月SCr分别为99.04、91.86 μmol/L,转换前后比较差异有统计学意义(P<0.01);CCr转换前为70.50ml/min,转换后升至78.27 ml/min.B组转换前和转换后1个月SCr分别为142.96、128.15/μmol/L,CCr分别为47.66、53.38 ml/min.C组SCr分别为97.09、88.34 μmol/L,CCr分别为69.38、75.66 ml/min.D组SCr分别为97.46、88.91 gmol/L,CCr分别为62.29、67.64 ml/min.C组总胆红素和直接胆红素分别由转换前的平均30.45和15.15 μmol/L降至转换后12.13和3.70μmol/L,转换前后比较差异有统计学意义(P<0.01).转换后主要不良事件包括:发热11例(7.0%);总胆固醇和甘油三酯升高者分别由转换前的36例(22.9%)和57例(36.3%)增至转换后的58例(36.9%)和73例(46.5%);转换前有蛋白尿13例(8.3%),转换后增至18例(11.5%). 结论 肾移植术后早期将CNI类药物转换为SRL安全、有效.SCr已升高者要尽早转换SRL治疗,CNI导致高胆红素、高尿酸血症和移植后肿瘤患者均可从转换SRL中受益.     

钙调磷酸酶抑制剂转换为西罗莫司治疗慢性移植物肾病的疗效研究

目的探讨钙调磷酸酶抑制剂(CNI)转换为西罗莫司治疗慢性移植物肾病(chronic allograft nephropathy,CAN)的疗效及不良反应。方法回顾性研究对象为2005年1月至2010年12月在西安交通大学医学院第一附属医院肾移植科随访的95例肾移植后并发CAN患者,术后均接受CNI为主的免疫抑制剂方案。所有患者均签署知情同意书,符合医学伦理学规定。患者确诊CAN后将CNI转换为西罗莫司。记录西罗莫司的维持剂量及血药浓度水平,了解转换治疗后血清肌酐(Scr)的变化,根据转换前Scr水平高低分为两组,Scr≥266μmol/L为Scr高水平组(22例),Scr<266μmol/L为Scr低水平组(73例);比较两组转换治疗后Scr变化幅度的差异;了解转换治疗的不良反应。结果 95例患者的随访时间6～48个月,西罗莫司的维持剂量为0.5～4mg/d(中位数为1.5mg/d),血药浓度为1.3～12ng/ml(中位数为5.4ng/ml)。Scr低水平组转换治疗效果明显高于Scr高水平组(P<0.05)。95例患者均未发生急性排斥反应。新发或蛋白尿加重32例(34%),新发或高脂血症加重25例(26%),1例患者发生肺部感染,经对症治疗后均治愈或缓解。结论 CNI类药物转换为西罗莫司治疗CAN是安全有效的,转换前Scr水平较低者的治疗效果优于转换前Scr水平较高者,转换后的主要并发症是蛋白尿和高脂血症。     

转换西罗莫司治疗肾移植后高胆红素血症的临床观察

目的：对转换西罗莫司（SRL）并撤除钙调磷酸酶抑制剂（CNI）类药物对高胆红素血症影响及其安全性和可行性进行临床观察。方法：2006年2月～2007年11月对肾移植后伴有高胆红素血症患者37例转换SRL并撤除CNI类药物，观察转换后总胆红素（TB）水平变化、血清肌酐（Scr）变化和不良事件发生情况。结果：TB和直接胆红素（DB）由转换前的30．45μmol／L和10．10μmol／L下降至转换后的12．13μmol／L和3．7μmol／L（P〈0．01）。Scr和血尿酸（Ua）转换后较转换前均有较明显降低，肌酐清除率（Ccr）有所提高。移植肾和患者全部存活。不良事件主要为高脂血症。结论：转换SRI．治疗肾移植后高胆红素血症是有效和安全的。     

肾移植后泌尿系统肿瘤患者应用西罗莫司替代钙调磷酸酶抑制剂九例

目的 探讨肾移植术后发生泌尿系统肿瘤的患者采用西罗莫司（SRL）替代钙调磷酸酶抑制剂（CNI）的有效性及安全性。方法 将9例肾移植术后发生泌尿系统肿瘤患者的CNI转换为SRL。所有患者停用CNI 12h后使用SRL，首次负荷剂量为3～4mg，维持剂量为0．5～1．5mg／d，以后根据SRL的血药浓度调整使用剂量。将SRL的血药浓度维持于：术后1年内6～10μg／L，1～2年4～8μg／L，2年以后3～6μg／L。药物转换过程中，监测患者的肿瘤复发情况，观察移植肾功能及排斥反应，统计药物的不良反应及药物转换前、后治疗费用的变化。结果 9例患者经药物转换后有8例病情稳定，肿瘤复发率明显降低。仅有1例患者肿瘤复发，于药物转换后12个月死亡。所有患者肾功能保持稳定并有所改善，均无明显不良反应发生，治疗费用也较药物转换前有不同程度的下降。结论 肾移植后发生泌尿系统肿瘤的患者使用SRL是安全和有效的，同时也可减少治疗费用。     

肾移植后发生尿路上皮肿瘤的患者转换西罗莫司治疗的临床观察

目的 观察肾移植后发生尿路上皮肿瘤的患者使用西罗莫司(SRL)联合低剂量钙调磷酸酶抑制剂(CNI)免疫抑制方案的有效性和安全性.方法 对15例肾移植后发生尿路上皮肿瘤的患者调整免疫抑制方案,采用SRL替代霉酚酸酯(或硫唑嘌呤).SRL的初始负荷剂量为2 mg,次日剂量为1 mg,之后根据SRL血药浓度调整维持剂量,使血药浓度维持在4～6μg/L;在其血药浓度稳定后将CNI减少至原用量的1/3.全部肿瘤患者均行手术治疗并辅以局部灌注化疗.转换SRL期间观察患者肿瘤的复发情况、移植肾功能及不良反应.结果 对15例患者随访2年中,9例肿瘤无复发;6例复发,其中2例复发2次,4例复发1次.在复发的患者中,4例肿瘤病理分级较转换SRL前降低,2例与转换前相同.所有复发的患者均再次行手术治疗.所有患者在使用SRL期间均未出现急性排斥反应,且其中11例患者肾功能指标较治疗前下降,4例肾功能保持稳定.转换治疗过程中出现高脂血症12例,不明原因发热4例,血小板减少3例,关节疼痛2例,所有不良反应经对症治疗后症状均有所好转.结论 肾移植后发生尿路上皮肿瘤的患者使用SRL联合低剂量CNI的免疫抑制方案是安全和有效的.     

免疫抑制剂对肾移植受者外周血单个核细胞Foxp3 mRNA表达的影响

目的 探讨免疫抑制剂对肾移植受者外周血单个核细胞中叉状头螺旋转录因子Foxp3 mRNA表达的影响.方法 采用实时荧光定量PCR法检测钙调磷酸蛋白酶抑制剂(CNI)组、雷帕霉素组、终末期肾病组以及正常对照组新鲜外周血单个核细胞中Foxp3 mRNA的表达水平,苦味酸法检测同期血肌酐浓度,比较各组间Foxp3 mRNA表达水平和肌酐浓度的差异.结果 CNI组(0.1089±0.0967)的外周血Foxp3 mRNA表达水平低于雷帕霉素组(1.1264±0.6565)、正常对照组(0.9380±0.3614)和终末期肾病组(1.1200±0.5703),差异均有统计学意义(均P<0.01).雷帕霉素组[(173.58±44.65) μmol/L]与CNI组[(150.45±46.21)μmol/L]血肌酐浓度差异无统计学意义(P>0.05).结论 CNI类免疫抑制剂抑制了肾移植后免疫耐受的诱导,而雷帕霉素可能参与了免疫耐受的诱导和维持.     

Conversion to sirolimus of patients with chronic allograft nephropathy—a retrospective analysis of outcome and influencing factors

Purpose

The purpose of this study was to analyse the outcome and its influencing factors in patients whose therapy was converted from calcineurin inhibitors (CNI) to sirolimus (SRL) due to chronic allograft nephropathy (CAN).

Materials and methods

Therapies of 78 patients (44 men) with CAN from three European transplant centres were converted from CNI therapy to SRL and followed 24 months. Slopes for creatinine clearance before and after conversion were calculated. Influencing factors were analysed by a multivariance analysis.

Results

The slope of the creatinine clearance improved significantly (?0.90 vs. ?0.34 ml min^?1 month^?1; p?<?0.01). In patients whose therapy was converted from cyclosporine A (CyA) to SRL, the slope improved significantly, whereas conversion from Tacrolimus (Tac) to SRL did not affect the slope. The benefit was more pronounced in (1) patients with low or moderate baseline creatinine clearance, (2) patients receiving SRL after conversion without additional mycophenolate mofetil and (3) patients with low or moderate proteinuria.

Conclusion

Conversion from CyA to SRL but not from Tac to CRL is associated with a reduced loss of renal allograft function in patients with CAN.     

The effect of sirolimus in the development of chronic allograft nephropathy

PURPOSE: The effect of sirolimus (SRL) in renal function was studied in renal transplant recipients. PATIENTS AND METHODS: We studied 20 patients who underwent live related kidney transplantation 1 to 2 years prior under cyclosporine (CsA) treatment and displayed serum creatinine values between 2 and 3 mg/dL. The patients were randomized into 2 groups prospectively. The calcineurin inhibitors (CNI) group continued taking CsA; the SRL group underwent a switch from CsA to SRL. Biopsies were performed to assess chronic allograft nephropathy (CAN) findings and TGFbeta1 in the transplanted kidneys at the beginning and the end of the study. Creatinine clearance, serum creatinine, and proteinuria values were detected in the beginning as well as at 1, 3, 6, and 12 months later. RESULTS: At the beginning of the study, the creatinine clearance and serum creatinine levels were 52.21 mL/min and 2.05 mg/dL in the CNI group and 47.76 mL/min and 2.13 mg/dL in the SRL group, respectively. At 12 months, these values were 48.11 mL/min and 2.57 mg/dL in the CNI group and 50.45 mL/min and 2.12 mg/dL in the SRL group, respectively. Creatinine clearance values between the 2 groups at 12 months were statistically different. Although it was not significant, there was a tendency toward decreases inflammatory infiltration and TGFbeta1 levels in the SRL group compared with the CNI group on the second biopsies. CONCLUSION: Pathologic findings of CAN development, serum creatinine, and creatinine clearance values were ameliorated in the SRL group. We concluded that SRL positively affected long-term graft survival.     

Conversion from a calcineurin inhibitor-based immunosuppressive regimen to everolimus in renal transplant recipients: effect on renal function and proteinuria

New immunosuppressive agents are being actively researched to avoid complications of chronic allograft nephropathy (CAN), calcineurin inhibitor (CNI) nephrotoxicity, and posttransplantation cancer. The family of mTOR inhibitors offers a unique immunosuppressive opportunity to avoid CNI toxicity and reduce the incidence of malignancy. Nevertheless, increasing data have demonstrated that sirolimus (SRL), the first mTOR introduced in the treatment of solid organ transplant recipients, induces proteinuria, an adverse event that could produce deterioration of long-term renal function. In this short-term study of patients followed for 1 to 16 months, we examined changes in renal function and proteinuria among renal transplant recipients converted from a CNI-based regimen to an everolimus (EVL)-based one, a recently introduced mTOR inhibitor. Our data showed that renal function can be optimized after conversion to EVL by up to 42% in recipients showing CAN grade 1 or 2, or CNI nephrotoxicity. Importantly, patients who improved their creatinine clearance did not show increased proteinuria measured in a voided specimen as the ratio of urinary protein and creatinine concentration (P/C). These results, if confirmed with long-term follow-up and a larger number of patients, would allow us to consider EVL as a promising agent for maintenance immunosuppressive regimens in kidney transplantation.     

在移植肾功能稳定的受者中主动撤除环孢素A的临床研究

目的 研究在移植肾功能稳定的受者中主动撤除环孢素A(CSA)对急性排斥反应发生率及肾功能的影响.方法 选择35例肾功能稳定的肾移植受者,其中尸体肾移植23例,亲属活体肾移植12例.除2例为再次肾移植外,其余均为初次肾移植.分别在肾移植术后6个月～6年时停用CsA,平均为术后(13.3±9.1)个月.撤除CsA后免疫抑制方案为:霉酚酸酯(MMF)+西罗莫司(SRL)+泼尼松(Pred).撤除CsA前有9例做了移植肾穿刺活检,8例测定了抗HLA抗体.结果 对35例受者随访6个月～4.5年,平均14.8个月.撤除CsA前、后血肌酐平均值分别为(88.1±15.5)μmol/L和(92.3±23.7)/μmol/L(P0.05).撤除CsA后,有2例经活检证实发生急性排斥反应,治疗后均逆转;CsA所致的毒副作用,如牙龈增生、糖耐量异常和多毛症等明显改善.9例移植肾活检中,有3例肾功能正常的受者已出现轻度慢性移植肾肾病表现.抗HLA抗体检测中,7例阴性者在撤除CsA前、后肾功能无明显变化.1例抗HLA抗体呈强阳性者在撤除CsA后进展为慢性移植肾肾病,恢复血液透析.结论 对移植肾功能稳定的受者在移植6个月后撤除CsA,转换为"霉酚酸酯+西罗莫司+泼尼松"的免疫抑制方案是安全的,不增加急性排斥反应风险;撤除CsA有利于消除一些与其相关的毒副作用;对抗HLA抗体呈强阳性者.撤除CsA后很难改变肾功能的进展.     

慢性肾功能损伤的肝移植受者转换为西罗莫司治疗的疗效观察

目的 观察慢性肾功能损伤的肝移植受者转换为西罗莫司治疗的疗效.方法 应用钙调磷酸酶抑制剂(CNI)并伴有慢性肾功能损伤的肝移植受者23例(其中19例应用他克莫司,4例应用环孢素A)转换为西罗莫司(SRL)治疗.SRL的起始剂量为4mg/d,次日为2 mg/d,应用高压液相色谱法测定全血SRL浓度,当血SRL浓度达5～8 μg/L后,停用CNI类药物,同时服用吗替麦考酚酯,1 g/d.记录受者入组前的基础血清肌酐(Cr)、肌酐清除率、肾小球滤过率(GFR),并分别于用药后第1、3、6、12和24个月时监测血SRL浓度、Cr、肌酐清除率、GFR,同时监测受者体重、血压、血细胞计数、肝功能和肝脏生化指标、血脂、尿蛋白.于用药后12个月时行肝脏穿刺活检确认有无排斥反应.结果 23例平均随访29.4个月,随访期内死亡2例,另21例于用药后1、3、6、12和24月时的Cr分别为(147.40±23.36)、(152.60±20.08)、(150.20±22.64)、(137.60±18.09)、(138.30±17.04)μmol/L,与Cr的基础值[(158.91±29.13)μmol/L]相比较,1、12、24个月时的差异有统计学意义(P＜0.05).用药后1、3、6、12和24月时的肌酐清除率分别为(0.97±0.18)、(0.99±0.14)、(1.00±0.17)、(1.07±0.29)、(1.14±0.12)ml/s,与基础肌酐清除率[(0.91±0.14)ml/s]相比较,1、12、24个月时的差异有统计学意义(P＜0.05).用药后1、3、6、12和24月时的GFR分别为(0.80±0.15)、(0.78±0.11)、(0.75±0.12)、(0.84±0.10)、(0.94±0.13),与基础GFR[(0.71±0.11)ml/s]相比较,1、12、24个月时的差异有统计学意义(P＜0.05).应用SRL后第1、3、6、12和24个月时,Cr≤123μmol/L者所占的比例分别为38.1％、33.3％、28.6％、47.6％和52.4％.随访期内无受者发生排斥反应.结论 慢性肾功能损伤的肝移植受者转换为西罗莫司治疗可改善其肾功能.转换治疗未增加排斥反应的发生率.     

Conversion to Sirolimus in Renal Transplant Recipients: A Single‐Center Experience

Maintenance immunosuppression with calcineurin inhibitors (CNI) following renal transplantation is associated with nephrotoxicity and accelerated graft loss. Sirolimus (SRL) is a nonnephrotoxic immunosuppressive agent. We retrospectively analyzed our experience with kidney transplant recipients who were converted from CNI to SRL. A total of 58 renal transplant recipients were converted from CNI to SRL. SRL was started at a dose of 0.075 mg/kg and, at the same time, CNI dose was reduced by 50% daily for 3 days. SRL trough levels were targeted between 8 and 12 ng/mL. When target trough levels were achieved, CNI was withdrawn. The main indications for switching were posttransplant malignancies (n = 32) and chronic allograft nephropathy (CAN) (n = 10). The mean time from transplantation to conversion was 84 ± 71 months. Mean serum creatinine level was 1.63 ± 0.52 mg/dL before conversion. Serum creatinine levels at the 1, 3, 6 months, and 1, 2, 3 years after conversion were 1.64 ± 0.58 mg/dL (P = 0.67), 1.52 ± 0.53 mg/dL (P = 0.414), 1.62 ± 0.62 mg/dL (P = 0.734), and 1.48 ± 0.58 mg/dL (P = 0.065), 1.58 ± 0.53 mg/dL (P = 0.854), 1.88 ± 0.77 mg/dL (P = 0.083), respectively. Daily proteinuria levels increased from 0.04 ± 0.11 g/day at baseline to 0.55 ± 1.33 g/day (P = 0.037) after conversion, in the responders group. In the nonresponders group, baseline proteinuria was 0.13 ± 0.25 g/day, and increased to 1.44 ± 2.44 g/day after conversion (P = 0.008). SRL was discontinued in 16 patients (31%) because of the occurrence of severe side effects. The proportion of patients remaining on SRL therapy over time was 43.1% at 1 year, 15.5% at 2 years after conversion, and 10.3% at 3 years after conversion. SRL conversion may be very useful in patients suffering from neoplasia; however, frequent side effects related with this intervention should be considered, and routine conversion from CNI to SRL to reduce nephrotoxicity should be discouraged.     

Predictors of Success in Conversion from Calcineurin Inhibitor to Sirolimus in Chronic Allograft Dysfunction

Chronic allograft dysfunction (CAD) is a major cause of graft loss in long-term kidney transplant recipients. To identify predictors of successful conversion from calcineurin inhibitor (CNI) to sirolimus (SRL) we investigated 59 renal transplant patients with CAD without histological signs of acute rejection. They received 12-15 mg SRL once, then 4-5 mg/day, target trough level 8-12 ng/mL. CNI dose was reduced by 50% simultaneously, and withdrawn at 1-2 months. Concomitant immunosuppression remained unchanged. After 1 year patient survival was 100% and graft survival 92%. In responders (54%) creatinine improved (2.75 +/- 0.75 to 2.22 +/- 0.64 mg/dL; p < 0.01). In nonresponders (46%) creatinine deteriorated (3.15 +/- 1.02 to 4.44 +/- 1.60 mg/dL; p < 0.01). Baseline renal function did not differ, however, baseline proteinuria (519 +/- 516 vs. 1532 +/- 867 mg/day, p < 0.01), histological grade of chronic allograft nephropathy (CAN) (1.2 +/- 0.5 vs. 1.9 +/- 0.6; p < 0.01), grade of vascular fibrous intimal thickening (1.2 +/- 0.7 vs. 1.7 +/- 0.7; p = 0.048) and number of acute rejections before conversion (0.73 +/- 0.69 vs. 1.27 +/- 0.96; p < 0.05) differed significantly between responders and nonresponders. In a multivariate analysis low proteinuria was the only independent variable. Proteinuria below 800 mg/day has a positive predictive value of 90%. Proteinuria at conversion below 800 mg/day is the only independent predictor for positive outcome in conversion from CNI to SRL in CAD.     

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.