Arteriolopathy in non-episode biopsies of renal transplant allograft

Purpose. We have been performing protocol biopsies since 1995 to predict the outcome of renal allograft. However, histopathological findings in renal allograft with stable function remain unclear. For this reason, we performed non-episode biopsy on long-surviving renal allograft and investigated the histopathological changes. Among the several diseases seen in non-episode biopsies, arteriolopathy, such as drug-induced nephropathy, is one of the most frequent diseases. However, it is unrelated to the dosage and the concentration of cyclosporine or tacrolimus. Consequently, we evaluated the clinicopathological findings of arteriolopathy in this study in order to clarify whether cyclosporine (CsA) or tacrolimus (FK506) is responsible for these findings. Materials and methods. We defined non-episode biopsy as a case with a serum creatinine level less than 2.0 mg/dL and containing less than 500 mg/dL of urinary protein. Final results showed that 71 cases were identified as non-episode biopsy. We then evaluated the histopathological findings and the clinical characteristics of these cases. Results. Thirty-two of the 71 non-episode biopsy specimens showed findings of arteriolopathy. The frequency and the severity of arteriolopathy are not concerned with dosage and concentration of CsA or FK506. The arteriolopathy seen in non-episode biopsy was related to the time of the biopsy and the kidney age. Arteriolopathy in non-episode biopsy also had a relationship with hypertension, suggesting that it is important to strictly control blood pressure for graft survival.     

Glucose metabolism in liver transplant recipients treated with FK 506 or cyclosporin in the European multicentre study

Abstract From September 1990 to January 1992, 545 liver transplant patients were randomised to treatment with either FK 506 and prednisolone or a conventional cyclosporin-based immunosuppressive regimen (CBIR). Eight European centres participated in the study. Adverse events were reported as defined by each centre. Hyperglycaemia was reported as an adverse event in 30.7% of patients receiving FK 506 compared with 20.5% in the CBIR group ( P < 0.01). Diabetes mellitus was reported in 17.2% of patients treated with FK 506 and 9.5% of CBIR-treated patients ( P < 0.05). Treatment with insulin was required in 12.0% of patients in the DK 506 treatment group and in 5% in the CBIR group at 6 months. Initially, higher doses of FK 506 were used. During the study, the protocol was changed to allow a lower dose of FK 506. When the early and late cohorts of patients were compared, the incidence of diabetes mellitus fell from 23.9% to 10.5% in FK 506-treated patients but remained relatively constant in the CBIR group (10.4% to 8.7%). The median cumulative doses of i.v. and p. o. corticosteroids were significantly greater in the CBIR group. Thus, in the overall series, the incidence of diabetes mellitus was significantly greater in the FK 506 group as compared with the CBIR group. However, when a lower FK 506 dose was used during the second half of the study, the difference in the incidence of diabetes mellitus disappeared.     

Rescue therapy with tacrolimus (FK 506) in renal transplant recipients -a Scandinavian multicenter analysis

Abstract All renal allograft recipients ( n = 32) in Sweden and Norway who were converted from cy-closporin(CyA)-based immunosuppression to FK 506 (tacrolimus) between October 1992 and June 1995 were analyzed retrospectively. The reasons for conversion were acute refractory rejection ( n = 21), chronic rejection ( n = 4), and suspected CyA toxicity ( n = 6); one patient was converted for psychological reasons. The mean time from transplantation to conversion was 29 (range 1–243) weeks and there was a mean follow-up of 46 (2–143) weeks. Overall graft survival was 59 %, with graft survival 52 % in patients converted because of acute rejection, 50 % in patients converted because of chronic rejection, and 83 % in patients converted because of CyA toxicity. There was no significant correlation between preconversion serum creatinine and outcome. Seventy-two percent of the patients had significant side effects during FK 506 treatment, the most frequent ones being neurological and gastrointestinal symptoms. These improved after dose reduction. Two patients became overimmunosup-pressed and developed lymphoma. One patient died of the primary kidney disease, hemolytic uraemic syndrome. We conclude that FK 506 therapy is able to salvage kidneys with acute refractory rejection and that it is an alternative in patients with CyA toxicity. However, the risk of overimmunosuppression must be considered.     

Rescue therapy with tacrolimus (FK 506) in renal transplant recipients —a Scandinavian multicenter analysis

All renal allograft recipients (n = 32) in Sweden and Norway who were converted from cyclosporin(CyA)-based immunosuppression to FK 506 (tacrolimus) between October 1992 and June 1995 were analyzed retrospectively. The reasons for conversion were acute refractory rejection (n = 21), chronic rejection (n = 4), and suspected CyA toxicity (n = 6); one patient was converted for psychological reasons. The mean time from transplantation to conversion was 29 (range 1–243) weeks and there was a mean follow-up of 46 (2–143) weeks. Overall graft survival was 59%, with graft survival 52% in patients converted because of acute rejection, 50% in patients converted because of chronic rejection, and 83% in patients converted because of CyA toxicity. There was no significant correlation between preconversion serum creatinine and outcome. Seventy-two percent of the patients had significant side effects during FK 506 treatment, the most frequent ones being neurological and gastrointestinal symptoms. These improved after dose reduction. Two patients became overimmunosuppressed and developed lymphoma. One patient died of the primary kidney disease, hemolytic uraemic syndrome. We conclude that FK 506 therapy is able to salvage kidneys with acute refractory rejection and that it is an alternative in patients with CyA toxicity. However, the risk of overimmunosuppression must be considered.     

Bone mass and mineral metabolism in liver transplant patients treated with FK506 or cyclosporine A

The purpose of this study was to compare the effects of Cyclosporine A (CyA) and FK506 on bone mass and mineral metabolism in liver transplantation (LT) patients. A prospective study was performed on 18 male patients who underwent LT treated with CyA, and 7 LT patients who received FK506. Bone mineral density (BMD) of the lumbar spine and proximal femur (DPX-L) was measured before and at 6, 12, and 24 months after transplantation. Moreover, intact parathyroid hormone (PTH) and 25-hydroxyvitamin D (25OHD) levels were determined at the same time. The cumulative dose of glucocorticoids was calculated in all patients. At 6 months, lumbar BMD decreased 5.2 ± 1.2 % (P=0.0005) and 2.9 ± 2.1 % (p=ns) in CyA and FK506 groups, respectively. Lumbar BMD reached baseline values at 1 year in the FK506 group and 2 years after LT in the CyA group. Moreover, significant intergroup differences in femoral neck BMD changes after 2 years of transplant were observed (CyA: −5.2 ± 1.97 versus FK506: +1.55 ± 2.2 %;P=0.039). In the first year posttransplant both groups showed a marked increase in PTH and 25OHD levels. The mean cumulative dose of glucocorticoids was higher in the CyA group (CyA group 11.06 ± 0.46 g versus FK 506 group 6.71 ± 0.42 g;P<0.001), and multiple linear regression analysis showed a negative correlation between BMD changes at the lumbar spine and mean cumulative dose of glucocorticoids (P=0.022). In conclusion, our data suggest that after liver transplantation treatment with FK506 shows a more favorable long-term effect on bone mass evolution than CyA therapy. These differences seem to be associated with the lower dose of glucocorticoids used in the FK506 group.     

Comparison of short and long-term renal function in liver transplant patients receiving cyclosporin or FK 506

Abstract Long-term renal function was compared in 49 liver recipients [25 patients received cyclosporin (CyA) and 24 patients received FK 5061 followed for a period of 1 year. Creatinine (CR) and glome-rular filtration rate (GFR) pre-transplantation (pre-Tx) and at 1, 3, 5, and 12 months post-Tx were recorded, as well as incidences of hyperkalemia, post-Tx hypertension, and insulin-dependent diabetes mellitus (IDDM) in the two groups. At 1 year post-Tx, the mean Cr had risen from baseline by 56% and 60% in the FK and CyA groups, respectively; the mean GFR had dropped by 32% in FK patients and by 27 % in CyA patients. Acute nephrotoxicity occurred in 1/25 CyA patients (217 required dialysis) and 9/26 FK patients (7/9 required dialysis; 211 were switched to CyA). None remained on dialysis at 3 months. Renal insufficiency persisted at 1 year in 7/16 patients with early toxicity (CyA, 4; FK, 3) and in 3 of the remaining 36 pts ( P < 0.001). Hyperkalemia occurred in 4/25 CyA, and in 12/24 FK patients ( P < 0.025), post-Tx hypertension occurred in 15 CyA, and 7 FK patients ( P < 0.05), and IDDM occurred in 4 CyA and 7 FK patients ( P = ns). FK 506 and CyA, thus, exerted similar chronic renal effects. Although acute renal insufficiency improved upon dose reduction, renal impairment was permanent in some cases.     

FK506和环孢素A对肾移植患者血脂影响的比较

目的：比较FK506和环孢素A(CsA)对肾移植患者术后脂质代谢的影响。方法：将以FK506或CsA为主要免疫抑制剂的肾移植患者209例分成FK506组和CsA组,对两组术后3个月、6个月和1年的血脂变化进行比较。结果：CsA组治疗术后血脂增高的比例均明显高于FK506组,且CsA组患者的治疗前、后血脂水平亦有明显差异。结论：肾移植患者治疗应用FK506比CsA可能会有效地降低高脂血症的发生率。     

Interaction of cyclosporine and FK506 with diuretics in transplant patients

BACKGROUND: The calcineurin inhibitors cyclosporine and FK506 are widely used for immunosuppression in solid organ transplantation. One of the side effects of these agents is renal magnesium wasting. The site of action and molecular mechanism of this effect are not known. We hypothesized that agents such as diuretics that cause renal magnesium wasting through a similar action would not have an additive effect on magnesium deficiency with calcineurin inhibitors. METHODS: The records of 50 heart transplant patients on calcineurin inhibitors were reviewed to determine levels of serum magnesium and required replacement dose of magnesium, diuretic usage, and other laboratory values. RESULTS: Loop diuretics did not change either the magnesium level or magnesium replacement requirements in patients on calcineurin inhibitors. In contrast, the thiazide diuretic resulted in an increase in serum magnesium and a decrease in magnesium replacement. Results were similar when the cyclosporine or FK506 groups were evaluated alone. Patients taking FK506 had lower serum magnesium values and higher requirements for magnesium replacement compared with patients taking cyclosporine. CONCLUSION: We conclude that calcineurin inhibitors and loop diuretics have a similar site of action.     

Clinical and Histopathologic Examination of Renal Allografts Treated with Tacrolimus (FK506) for at Least One Year

Background : We clinically and pathologically analyzed renal allografts from 19 renal transplant patients treated with tacrolimus (FK506) for more than 1 year.
Methods : Twenty-six renal allograft biopsy specimens from 19 renal transplant patients who underwent transplantations between 1991 and 1 993 were evaluated. Thirteen biopsies were performed from stable functioning renal allografts with informed consent (nonepisode biopsy) and the other 13 were from dysfunctional renal allografts with a clinical indication for biopsy (episode biopsy).
Results : The main pathologic diagnoses (some overlap) were acute rejection (AR; n = 4), chronic rejection (CR;n = 5), AR + CR(n=4), recurrent IgA nephropathy (n = 5), normal findings (n = 2), minimal-type chronic FK506 nephropathy (n = 9), and mild-type FK506 nephropathy (n = 11). Of the nonepisode biopsies, 7 and 4 biopsies showed minimal-type and mild-type chronic FK506 nephropathy, respectively. Chronic FK506 nephropathy consisted of rough and foamy tubular vacuolization (5 biopsies), arteriolopathy (angio-degeneration of the arteriolar wall; 20 biopsies), focal segmental glomerulosclerosis (4 biopsies) and the striped form of interstitial fibrosis (11 biopsies). The serum creatinine levels of patients in the mild-type chronic FK506 nephropathy group, which included 7 episode biopsies, were statistically higher than those in the minimum-type chronic FK506-nephropathy group (P < 0.001).
Conclusions : This study demonstrates that chronic FK506 nephropathy consists primarily of arteriolopathy manifesting as insudative hyalinosis of the arteriolar wall, and suggests that mild-type chronic FK506 nephropathy is a condition which may lead to deterioration of renal allograft function.     

肾移植术后长期应用他克莫司的临床观察

目的　探讨肾移植术后长期应用他克莫司 (FK5 0 6 )的临床疗效和安全性。方法　对肾移植术后符合入选条件的 12 6例服用FK5 0 6和 10 9例服用环孢素A(CsA)的患者进行为期 3年的随访。详细记录了患者的服药剂量、FK5 0 6和CsA谷值浓度 ,观察排斥反应、毒副反应发生率 ,计算人 /肾存活率。结果　FK5 0 6组和CsA组 1、3年人 /肾存活率分别为 :98.4 % / 96 .8%、95 .2 % / 90 .5 %和 97.2 % / 96 .3%、94 .4 % / 89.0 % ;急性排斥反应发生率分别为 :13.5 %和 19.3% (P <0 .0 5 ) ;慢性排斥反应发生率分别为 :3.2 %和 8.3% (P <0 .0 5 ) ;糖代谢紊乱发生率分别为 :16 .7%和 9.2 % (P<0 .0 5 ) ;神经精神毒性分别为 :14 .3%和 12 .0 % ;肝功能损害分别为 :6 .3%和 10 .1% (P <0 .0 5 ) ;肾功能损害分别为 :3.2 %和 8.3% (P <0 .0 5 ) ;脱发分别为 :5 .6 %和 0 (P <0 .0 5 ) ;感染分别为 :7.1%和 6 .4 %。结论　FK5 0 6长期使用疗效确切 ,毒副反应发生率较低。     

Tacrolimus and cyclosporine efficacy in high-risk kidney transplantation on behalf of the European Multicentre Tacrolimus (FK506) Renal Study Group

Abstract The efficacy and safety of tacrolimus- and cyclosporine-based immunosuppressive regimens were compared in a prospectively defined subgroup of kidney transplant recipients from the European, open, multicentre, 2:1 randomised, parallel group study. Patients were stratified as high risk for immunological events if they had a panel-reactive antibodies grade greater than 80% and/or a previous transplant functional for less than 1 year. The primary efficacy variables evaluated were the incidence of acute rejection, steroid usage and patient and graft survival. Safety was assessed based on adverse events and laboratory evaluations. At 1 year, the tacrolimus group ( n = 22) had a lower incidence of biopsy-proven acute rejection (31.8%) and a higher graft survival (86.0%) than the 11 patients in the cyclosporine group (54.5 % and 72.0 %, respectively). The frequencies of adverse events were similar between the two groups. The tacrolimus regimen appears more beneficial for high risk patients than cyclosporine.     

TIRC7 is induced in rejected human kidneys and anti-TIRC7 mAb with FK506 prolongs survival of kidney allografts in rats

TIRC7 delivers essential signals during immune activation as antibodies targeting TIRC7 inhibit lymphocyte proliferation and Th1 cytokine expression in vitro and prolonged kidney and heart allograft survival in vivo. Immunohistochemical analysis of biopsy specimens from human renal allografts undergoing rejection despite treatment with Calcineurin inhibitors (CI) showed elevated TIRC7 expression. Accordingly, with a view to clinical application, we evaluated the therapeutic effect of a chimerized anti-TIRC7 mAb in combination with Tacrolimus (FK506) using a rat kidney transplantation model (DA to Lewis). The combination of sub-therapeutic doses of both compounds significantly (p<0.05) prolonged the median graft survival to 19.5 days compared to monotherapy with FK506 (median survival, 7d) or mAb against TIRC7 (7d). These results suggest a potential synergism of anti-TIRC7 mAb and FK506 action, which could be developed into a novel combination therapy in the clinic by lowering side effects of present CI treatment. Moreover, the identification of TIRC7 in graft infiltrating lymphocytes might serve as a diagnostic marker to detect allograft rejection.     

Diabetes as a complication of tacrolimus (FK506) in pediatric renal transplant patients

Three cases of insulin-requiring diabetes mellitus associated with tacrolimus (FK506) therapy in pediatric renal transplant patients are presented. New-onset diabetes mellitus has been reported with tacrolimus therapy post liver and kidney transplants in up to 12% of adult patients, but is thought to be rare in pediatrics. Although insulin requirement with tacrolimus therapy has been occasionally reported in adolescent patients post liver transplant, only a single case in a pediatric kidney transplant recipient has been previously documented. These cases illustrate the significant diabetogenic effect of tacrolimus in pediatric renal transplant patients. As the use of tacrolimus becomes more prevalent in pediatric kidney transplantation, pediatric nephrologists should be aware of this potential complication.     

Hyperlipidemia in pediatric kidney transplant recipients treated with cyclosporine

Hyperlipidemia is a risk factor for cardiovascular disease in adult kidney transplant (Tx) recipients. We sought to determine the prevalence of, and the risk factors associated with, hyperlipidemia in pediatric kidney Tx recipients on cyclosporine (CsA). We identified 59 patients (mean age 8.2+/-5.7 years) transplanted between 1 January 1991 and 31 December 1993. Pre Tx, 34% had elevated total cholesterol [TC >200 mg/dl (5.17 mmol/l)]; 54% had elevated triglycerides [TG >200 mg/dl (2.26 mmol/L)]. Mean TG was higher pre Tx in dialysis (versus nondialysis) patients: 306 mg/dl (3.46 mmol/l) versus 228 mg/dl (2.58 mmol/l) ( P=0.04). Mean TC was higher in peritoneal dialysis than hemodialysis patients: 222 mg/dl (5.74 mmol/l) versus 169 mg/dl (4.37 mmol/l) ( P=0.03). Pre Tx and 3-year values correlated (TC, r=0.49, P=0.0008; TG, r=0.41, P=0.001); 3- and 5-year TC values correlated ( r=0.57, P=0.003). At 5 years post Tx, 41% of the recipients had elevated TC; 14% had elevated TG. Recipients with elevated TC had higher mean CsA concentrations at 1 year post Tx ( P=0.03). Recipients with elevated TG tended to receive more prednisone ( P=0.06). At 5 years post Tx, recipients had a high prevalence of hyperlipidemia. The identification and treatment of hyperlipidemia should be included in pediatric kidney Tx protocols.     

Pharmacological preconditioning with low-dose cyclosporine or FK506 reduces subsequent ischemia/reperfusion injury in rat kidney.

BACKGROUND: Ischemia/reperfusion (I/R) injury in the early posttransplant period is closely associated with delayed recovery of graft function, increased acute rejection, and late allograft dysfunction. Pharmacological preconditioning with low-dose cyclosporine (CsA) or FK506 was performed to induce ischemic tolerance in rat kidney with I/R injury. METHODS: Low-dose CsA (3 mg/kg, administered i.v.) or FK506 (0.3 mg/kg i.v.) were used to induce ischemic tolerance in Sprague-Dawley rats, and the induction of heat shock protein (hsp) 70 by CsA or FK506 was evaluated overtime. Rats were pretreated with CsA or FK506 6 hr before I/R injury when hsp70 was maximally expressed, and were killed 24 hr later. The effect of pharmacological preconditioning on subsequent I/R injury was evaluated in terms of renal function, histopathology score, assays for apoptosis (DNA fragmentation analysis, TUNEL staining, expressions of pro-apoptotic genes, and caspase activity), and the expression of inflammatory cytokine genes (interleukin-1 and tumor necrosis factor-alpha). RESULTS: Preconditioning with low-dose CsA or FK506 significantly improved renal function and renal histology, compared to rats with I/R injury. Apoptotic cell death (typical DNA laddering and increased TUNEL-positive cells) in rat kidneys with I/R injury, was decreased by pretreatment with low-dose CsA or FK506. Increased expression of pro-apoptotic genes (Fas, Fas-ligand, caspase 1 and 3) and activated caspases in ischemic rat kidneys were decreased after CsA or FK506 pretreatment. CONCLUSIONS: Pretreatment with low-dose CsA or FK506 prevents subsequent I/R injury, and this effect may be related to the induction of hsp70. Pretreatment of renal donors with low-dose CsA or FK506 may result in an improvement in immediate posttransplant function.