A prospective randomized trial of FK506-based immunosuppression after renal transplantation

Blood concentrations of tacrolimus upon conversion from rabeprazole to vonoprazan in renal transplant recipients: Correlation with cytochrome P450 gene polymorphisms

We evaluated the impact of vonoprazan on blood concentrations of tacrolimus via a retrospective analysis of 52 renal transplant recipients who took tacrolimus and converted from rabeprazole to vonoprazan between August 2018 and September 2019. We compared tacrolimus trough levels upon conversion among groups that were classified based on cytochrome P450 (CYP) gene polymorphisms. CYP3A5 groups were heterozygous or homozygous for CYP3A5∗1 and CYP3A5∗3 alleles. CYP2C19 genotypes were classified as extensive (∗1/∗1), intermediate (∗1/∗2 and ∗1/∗3) or poor metabolizers (∗2/∗2, ∗2/∗3 and ∗3/∗3). Tacrolimus trough levels increased only 0.3 ng/mL upon conversion in the CYP3A5∗3/∗3 group: 5.8 [3.4-7.2] vs 6.1 [3.8-7.9]; p = 0.06. No statistically significance changes in tacrolimus levels also occurred in the CYP3A5∗1/∗1 or CYP3A5∗1/∗3 groups. Subgroup analyses of CYP3A5∗3/∗3 demonstrated low changes for all three CYP2C19 subgroups: 5.2 [4.3-6.5] vs 6.2 [4.3-7.9]; p = 0.07, 6.1 [3.4-7.2] vs 6.7 [4.6-7.9]; p = 0.12 and 5.4 [3.6-6.5] vs 4.7 [3.8-6.3]; p = 1.00, respectively. Conversion to vonoprazan thus resulted in little increase of tacrolimus trough levels, even in the group predicted to be most susceptible (CYP3A5∗3/∗3 and 2C19∗1/∗1), thus supporting the safety of concomitant use of vonoprazan with tacrolimus.

Overview of Immunosuppressive Therapy in Solid Organ Transplantation

Mechanisms of rejection, new pharmacologic approaches, and genomic medicine are major foci for current research in transplantation. It is hoped that these new agents and personalized immunosuppression will provide for less toxic regimens that are effective in preventing both acute and chronic allograft rejection. Until new agents are available, practitioners must use various combinations of currently approved agents to find the best regimens for improved long-term outcomes.

Hypomagnesemia and increased risk of new-onset diabetes mellitus after transplantation in pediatric renal transplant recipients

BACKGROUND

New-onset diabetes after transplantation (NODAT) is a significant co-morbidity following kidney transplantation. Lower post-transplant serum magnesium levels have been found to be an independent risk factor for NODAT in adult kidney transplant recipients.

METHODS

We undertook a retrospective analysis of risk factors for NODAT in pediatric renal transplant recipients at our institution with the aim of determining if hypomagnesemia confers a significant risk of developing NODAT in this patient population.

RESULTS

A total of 173 children with a median age at transplantation of 7.0 (range 1.3-17.5) years were included. Hypomagnesemia was found to be a significant independent risk factor for NODAT (p = 0.01). High trough tacrolimus levels were also independently associated with NODAT (p < 0.001). There was no significant association between NODAT and body mass index at the time of transplantation, monthly cumulative steroid dose or post-transplant cytomegalovirus viremia (p = 0.9, 0.6 and 0.7, respectively).

CONCLUSIONS

This study identifies hypomagnesemia as a significant independent risk factor for the development of NODAT in pediatric renal transplant recipients. Given the clear association between hypomagnesemia and NODAT in both adults and children following renal transplantation, further studies are merited to clarify the etiology of this association and to examine the effect of magnesium supplementation on NODAT.

Steroid avoidance or withdrawal for kidney transplant recipients

BACKGROUND

Steroid-sparing strategies have been attempted in recent decades to avoid morbidity from long-term steroid intake among kidney transplant recipients. Previous systematic reviews of steroid withdrawal after kidney transplantation have shown a significant increase in acute rejection. There are various protocols to withdraw steroids after kidney transplantation and their possible benefits or harms are subject to systematic review. This is an update of a review first published in 2009.

OBJECTIVES

To evaluate the benefits and harms of steroid withdrawal or avoidance for kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 15 February 2016 through contact with the Information Specialist using search terms relevant to this review.

SELECTION CRITERIA

All randomised and quasi-randomised controlled trials (RCTs) in which steroids were avoided or withdrawn at any time point after kidney transplantation were included.

DATA COLLECTION AND ANALYSIS

Assessment of risk of bias and data extraction was performed by two authors independently and disagreement resolved by discussion. Statistical analyses were performed using the random-effects model and dichotomous outcomes were reported as relative risk (RR) and continuous outcomes as mean difference (MD) with 95% confidence intervals.

MAIN RESULTS

We included 48 studies (224 reports) that involved 7803 randomised participants. Of these, three studies were conducted in children (346 participants). The 2009 review included 30 studies (94 reports, 5949 participants). Risk of bias was assessed as low for sequence generation in 19 studies and allocation concealment in 14 studies. Incomplete outcome data were adequately addressed in 22 studies and 37 were free of selective reporting.The 48 included studies evaluated three different comparisons: steroid avoidance or withdrawal compared with steroid maintenance, and steroid avoidance compared with steroid withdrawal. For the adult studies there was no significant difference in patient mortality either in studies comparing steroid withdrawal versus steroid maintenance (10 studies, 1913 participants, death at one year post transplantation: RR 0.68, 95% CI 0.36 to 1.30) or in studies comparing steroid avoidance versus steroid maintenance (10 studies, 1462 participants, death at one year after transplantation: RR 0.96, 95% CI 0.52 to 1.80). Similarly no significant difference in graft loss was found comparing steroid withdrawal versus steroid maintenance (8 studies, 1817 participants, graft loss excluding death with functioning graft at one year after transplantation: RR 1.17, 95% CI 0.72 to 1.92) and comparing steroid avoidance versus steroid maintenance (7 studies, 1211 participants, graft loss excluding death with functioning graft at one year after transplantation: RR 1.09, 95% CI 0.64 to 1.86). The risk of acute rejection significantly increased in patients treated with steroids for less than 14 days after transplantation (7 studies, 835 participants: RR 1.58, 95% CI 1.08 to 2.30) and in patients who were withdrawn from steroids at a later time point after transplantation (10 studies, 1913 participants, RR 1.77, 95% CI 1.20 to 2.61). There was no evidence to suggest a difference in harmful events, such as infection and malignancy, in adult kidney transplant recipients. The effect of steroid withdrawal in children is unclear.

AUTHORS' CONCLUSIONS

This updated review increases the evidence that steroid avoidance and withdrawal after kidney transplantation significantly increase the risk of acute rejection. There was no evidence to suggest a difference in patient mortality or graft loss up to five year after transplantation, but long-term consequences of steroid avoidance and withdrawal remain unclear until today, because prospective long-term studies have not been conducted.

Tacrolimus in transplant rejection

INTRODUCTION

Renal transplantation is the best therapy for patients with end-stage renal disease. To avoid graft rejection, adequate immunosuppressive therapy is crucial. Tacrolimus is approved for prophylaxis of transplant rejection in liver, kidney or heart allograft recipients and for the treatment of allograft rejection resistant to treatment with other immunosuppressive medicinal products.

AREAS COVERED

The objective of this review is to summarize the clinical efficacy of tacrolimus in renal transplantation with special emphasis on acute rejection, refractory rejection and nephrotoxicity and post-transplant diabetes mellitus as typical adverse effects of the drug.

EXPERT OPINION

Since its approval in 1994, tacrolimus has proven its efficacy as a cornerstone of modern immunosuppressive therapy not only in numerous randomized clinical trials but also in standard clinical care. Compared with cyclosporine, the use of tacrolimus in renal transplant recipients is associated with a reduced risk for acute rejection, a reduction in the occurrence of steroid-resistant rejection and a better graft function. The avoidance of nephrotoxicity and especially post-transplant diabetes mellitus are of major interest in long-term care of renal transplant recipients.

Distinct effects of omeprazole and rabeprazole on the tacrolimus blood concentration in a kidney transplant recipient

Proton-pump inhibitors (PPIs, e.g. omeprazole and rabeprazole) are often administered to transplant patients as a treatment or prophylaxis for ulcers after surgery. Since tacrolimus and PPIs share the CYP3A4 system for metabolism, pharmacokinetic interactions are anticipated when they are administered simultaneously. We present a Japanese male patient who underwent a living-donor kidney transplantation having received tacrolimus, mycophenolate mofetil, and prednisolone for immunosuppression. The concentration/dose (C/D) ratio for tacrolimus was markedly higher during the period of treatment with omeprazole than ranitidine or rabeprazole. The results of liver functional tests were within the normal range during the use of these three antacid drugs. Since the higher C/D ratio for tacrolimus when omeprazole was being administered did not result from a decrease in the elimination of tacrolimus due to hepatic dysfunction, drug interaction between omeprazole and tacrolimus was strongly suspected. The present case indicates that rabeprazole can be used safely in place of omeprazole in kidney transplant recipients receiving tacrolimus.

Immunosuppressive drug-induced diabetes

Post-transplant diabetes mellitus (PTDM) has emerged as a major adverse effect of immunosuppressive drugs (ISD). As recipients of organ transplants survive longer, the complications of diabetes mellitus have assumed greater importance. The predominant factor for causing PTDM by corticosteroids seems to be the aggravation of insulin resistance, however several studies have displayed deleterious effects on insulin secretion and beta-cells. Calcineurin inhibitors induce PTDM by a number of mechanisms, including decreased insulin secretion and a direct toxic effect on the pancreatic beta-cells. Recent in vitro studies stress on the increased apoptosis of beta-cells when exposed to these drugs. Studies involving other immunosuppressive agents (mycophenolate mofetil [MMF], sirolimus) are scarcer and lead to conflicting results, while daclizumab seems to have a neutral effect. Clinical studies have consistently shown a greater potential of tacrolimus to induce PTDM compared with cyclosporine. Reducing PTDM incidence is a feasible goal while using corticosteroid-sparing regimens and/or lower tacrolimus trough levels. In patients developing PTDM, conversion from tacrolimus to cyclosporine could improve or reverse glucose tolerance abnormalities. In the absence of well-designed studies in this specific indication, treatment of PTDM is based on the same principles as type 2 diabetes mellitus. Thiazolidinediones do not display any pharmacological interaction with calcineurin inhibitors, but their safety and efficacy in PTDM need to be confirmed in large-scale randomized trials. Use of sulfonylureas has to be cautious regarding the suspected interaction of some of them with calcineurin inhibitors. If needed, insulin regimens have to be adapted in patients who display the particular glycaemic profile of corticosteroid-induced diabetes. Incretin-based therapies, due to their specific action on beta-cell apoptosis and proliferation, raise promises that have to be confirmed in clinical studies. Until methods for inducing specific graft tolerance become available, immunosuppressive regimens should be tailored to the individual patient on the basis of predictive criteria for the development of PTDM.

Steroid withdrawal in living donor renal transplant recipients using tacrolimus and cyclosporine: a randomized prospective study*

Steroids have been a mainstay of immunosuppressive regimens in renal transplantation despite their adverse effects. The introduction of new immunosuppressant has improved the survival rates and prompted trials of steroid withdrawal. We conducted a randomized prospective study to compare steroid withdrawal at 6 months post-transplant between tacrolimus + mycophenolate mofetil (MMF) (FK group) versus cyclosporine A + MMF (CsA group). Steroid was withdrawn at 6 months post-transplant under the condition of no rejection episode proven by biopsy and maintenance of serum creatinine level <2.0 mg/dl. Fourteen recipients were excluded because of acute rejection within 6 months or protocol violation. Steroid could be tapered off in 62 in FK group and 55 in CsA. Three cases in FK group and five in CsA had acute rejection within another 6 months after steroid withdrawal (P > 0.05). At 12 months, the incidence of post-transplant diabetes was 18.6% vs. 8.0% in FK and CsA group. And hypercholesterolemia was presented in 8.5% vs. 2.0%, hypertension in 47.5% vs. 56.0%, and serum creatinine level 1.18 +/- 0.24 mg/dl vs. 1.18 +/- 0.20 mg/dl, respectively (P > 0.05). Steroid withdrawal may be carried out successfully using both FK and CsA with MMF, but long-term follow-up is necessary.

Oral health in renal transplant recipients administered cyclosporin A or tacrolimus

OBJECTIVE

The aim of this study was to determine the oral status of renal transplant recipients receiving cyclosporin A (CsA) or tacrolimus (FK-506) as immunosuppressant.

SUBJECTS AND METHODS

A total of 88 renal transplant recipients receiving CsA (63 men and 25 women, mean age 51.4 years) and 67 receiving FK-506 (57 men and 10 women, mean age 33.5 years) were included in the study. Donor type, histocompatibility, cold ischemia time and prior delayed graft function were similar between the two groups. Demographics and pharmacological data were recorded for all subjects.

RESULTS

The results demonstrated that CsA caused a greater number of oral diseases. A greater number of gingival overgrowth was present in patients treated with CsA. However, the combined use with calcium channel blockers increased the gingival overgrowth number. The occurrence of candida in saliva was observed in 80 renal recipients treated with CsA and 20 treated with FK-506. The presence of squamous oral carcinoma (n = 3) and herpes simplex (n = 10) was observed in patients treated with CsA. These alterations were not observed in renal recipients treated with FK-506.

CONCLUSIONS

Renal recipients constitute a high-risk group for oral diseases, as they are immunocompromised. However, the FK-506 regime appears to ameliorate this effect, compared with CsA. Adequate pre- and post-transplant oral health care is recommended for these subjects, irrespective of the time interval for which the drug is administered.

African-American renal transplant recipients benefit from early corticosteroid withdrawal under modern immunosuppression

African-Americans (AAs) have historically been considered high-risk renal transplant recipients due to increased rejection rates and reduced long-term graft survival. As a result, AAs are often excluded from corticosteroid withdrawal (CSWD) protocols. Modern immunosuppression has reduced rejections and improved graft survival in AAs and may allow successful CSWD. Outcomes in 56 AAs were compared to 56 non-AAs. All patients were enrolled in one of four early CSWD protocols. Results are reported as AA versus non-AA. Acute rejection at 1-year was 23% and 18%; (p = NS); creatinine clearance at 1-year was 75 versus 80 mL/min (p = NS); patient and graft survival was 96% versus 98% and 91% versus 91%; (p = NS). AAs benefit from early CSWD with significantly improved blood pressure, LDL < 130 mg/dL and HDL > 45 mg/dL at 1-year, post-transplant diabetes of 8.7%, and mean weight change at 1-year of 4.8 +/- 7.2 kg. In conclusion, early CSWD in AAs is associated with acceptable rejection rates, excellent patient and graft survival, and improved cardiovascular risk, indicating that the risks and benefits of early CSWD are similar between AAs and non-AAs. Additional follow-up is needed to determine long-term renal function, graft survival, and cardiovascular risk in AAs with early CSWD.

Pharmacokinetic Considerations Relating to Tacrolimus Dosing in the Elderly

Relaxation of the upper age limits for solid organ transplantation coupled with improvements in post-transplant survival have resulted in greater numbers of elderly patients receiving immunosuppressant drugs such as tacrolimus. Tacrolimus is a potent agent with a narrow therapeutic window and large inter- and intraindividual pharmacokinetic variability. Numerous physiological changes occur with aging that could potentially affect the pharmacokinetics of tacrolimus and, hence, patient dosage requirements. Tacrolimus is primarily metabolised by cytochrome P450 (CYP) 3A enzymes in the gut wall and liver. It is also a substrate for P-glycoprotein, which counter-transports diffused tacrolimus out of intestinal cells and back into the gut lumen. Age-associated alterations in CYP 3A and P-glycoprotein expression and/or activity, along with liver mass and body composition changes, would be expected to affect the pharmacokinetics of tacrolimus in the elderly. However, interindividual variation in these processes may mask any changes caused by aging. More investigation is needed into the impact aging has on CYP and P-glycoprotein activity and expression. No single-dose, intense blood-sampling study has specifically compared the pharmacokinetics of tacrolimus across different patient age groups. However, five population pharmacokinetic studies, one in kidney, one in bone marrow and three in liver transplant recipients, have investigated age as a co-variate. None found a significant influence for age on tacrolimus bioavailability, volume of distribution or clearance. The number of elderly patients included in each study, however, was not documented and may have been only small. It is likely that inter- and intraindividual pharmacokinetic variability associated with tacrolimus increase in elderly populations. In addition to pharmacokinetic differences, donor organ viability, multiple co-morbidity, polypharmacy and immunological changes need to be considered when using tacrolimus in the elderly. Aging is associated with decreased immunoresponsiveness, a slower body repair process and increased drug adverse effects. Elderly liver and kidney transplant recipients are more likely to develop new-onset diabetes mellitus than younger patients. Elderly transplant recipients exhibit higher mortality from infectious and cardiovascular causes than younger patients but may be less likely to develop acute rejection. Elderly kidney recipients have a higher potential for chronic allograft nephropathy, and a single rejection episode can be more devastating. There is a paucity of information on optimal tacrolimus dosage and target trough concentration in the elderly. The therapeutic window for tacrolimus concentrations may be narrower. Further integrated pharmacokinetic-pharmacodynamic studies of tacrolimus are required. It would appear reasonable, based on current knowledge, to commence tacrolimus at similar doses as those used in younger patients. Maintenance dose requirements over the longer term may be lower in the elderly, but the increased variability in kinetics and the variety of factors that impact on dosage suggest that patient care needs to be based around more frequent monitoring in this age group.

Effect of immunosuppressive agents on long-term survival of renal transplant recipients: focus on the cardiovascular risk

In the control of acute rejection, attention is being focused more and more on the long-term adverse effects of the immunosuppressive agents used. Since cardiovascular disease is the main cause of death in renal transplant recipients, optimal control of cardiovascular risk factors is essential in the long-term management of these patients. Unfortunately, several commonly used immunosuppressive drugs interfere with the cardiovascular system. In this review, the cardiovascular adverse effects of the immunosuppressive agents currently used for maintenance immunosuppression are thoroughly discussed. Optimising immunosuppression means finding a balance between efficacy and safety. Corticosteroids induce endothelial dysfunction, hypertension, hyperlipidaemia and diabetes mellitus, and impair fibrinolysis. The use of corticosteroids in transplant recipients is undesirable, not only because of their cardiovascular effects, but also because they induce such adverse effects as osteoporosis, obesity, and atrophy of the skin and vessel wall. Calcineurin inhibitors are the most powerful agents for maintenance immunosuppression. The calcineurin inhibitor ciclosporin (cyclosporine) not only induces these same adverse effects as corticosteroids but is also nephrotoxic. Tacrolimus has a more favourable cardiovascular risk profile than ciclosporin and is also less nephrotoxic. It has little or no effect on blood pressure and serum lipids; however, its diabetogenic effect is more prominent in the period immediately following transplantation, although at maintenance dosages, the diabetogenic effect appears to be comparable to that of ciclosporin. The diabetogenic effect of tacrolimus can be managed by reducing the dose of tacrolimus and early corticosteroid withdrawal. The effect of tacrolimus on endothelial function has not been completely elucidated. The proliferation inhibitors azathioprine and mycophenolate mofetil (MMF) have little effect on the cardiovascular system. Yet, indirectly, by inducing anaemia, they may lead to left ventricular hypertrophy. MMF is an attractive alternative to azathioprine because of its higher potency and possibly lower risk of malignancies. Sirolimus also induces anaemia, but may be promising because of its antiproliferative features. Whether the hyperlipidaemia induced by sirolimus counteracts its beneficial effects is, as yet, unknown. It may be combined with MMF, however, initial attempts resulted in severe mouth ulcers.

GLUCOSE METABOLISM AFTER PANCREAS TRANSPLANTATION: CYCLOSPORINE VERSUS TACROLIMUS

BACKGROUND

The results of the new immunosuppressants in simultaneous pancreas-kidney transplantation (SPK) concerning organ survival and rejection rates are excellent. Tacrolimus as well as cyclosporine are assumed to be diabetogenic; however, there are no comparative studies investigating their effects on glucose metabolism.

METHODS

One hundred thirty-six type 1 diabetic patients who had undergone successful SPK were investigated. Glucose and insulin levels during an oral glucose tolerance test as well as hemoglobin (Hb) A1c were analyzed. Investigations were performed early (3 months, n = 136) and late (3 years, n = 83) after transplantation. Graft recipients were grouped according to the first-line immunosuppression: group 1, cyclosporine; group 2, tacrolimus. There were no differences concerning age, gender, body mass index, and renal function between the groups.

RESULTS

Early after transplantation, there was no difference between the groups concerning fasting glucose, HbA1c levels, basal and stimulated insulin secretion, and incidence of normal glucose tolerance. Late after transplantation, the incidence of a normal glucose tolerance tended to be lower (70% vs. 78%), whereas HbA1c (5.3% vs. 5.0%) and fasting glucose (81 vs. 78 mg/dL) levels tended to be higher in tacrolimus-treated patients. However, these differences were not significant. Insulin secretion was not reduced in the tacrolimus group.

CONCLUSIONS

Concerning glucose metabolism and secretory capacity of the pancreas graft, no significant differences were found comparing tacrolimus- versus cyclosporine-treated graft recipients.

Steroid-withdrawal at 3 days after renal transplantation with anti-IL-2 receptor alpha therapy: a prospective, randomized, multicenter study

Steroids have been included in most immunosuppressive regimens after renal transplantation, but are feared for their side-effects. We conducted a prospective multicenter study to investigate whether it is feasible to withdraw steroids early after transplantation with the use of anti-IL-2Ralpha induction, tacrolimus and mycophenolate mofetil (MMF). A total of 364 patients were randomized to receive either two doses of daclizumab (1 mg/kg) and, for the first 3 days, 100 mg of prednisolone (daclizumab group n = 186), or steroids (tapered to 0 mg at week 16; controls n = 178). All patients received tacrolimus and MMF. The incidence of biopsy-confirmed acute rejection at 12 months was not different between the daclizumab group (15%) and the controls (14%) (95% confidence interval of difference: -6 to + 8%, NS). Graft survival at 12 months was comparable in the two groups (daclizumab group: 91%; controls: 90%). Mean arterial blood pressure, serum lipids, and incidence of patients with hyperglycemia were temporary lower in the daclizumab group compared with controls. The immunosuppressive regimen of the daclizumab group was associated with increased costs. In conclusion, with the use of anti-IL-2Ra induction and daily therapy with tacrolimus and MMF it is feasible to withdraw steroids at 3 days after renal transplantation.

Lansoprazole—Tacrolimus Interaction in Japanese Transplant Recipient with CYP2C19 Polymorphism

OBJECTIVE

To report a patient with a high tacrolimus blood concentration after lansoprazole administration and assess the potential interaction between tacrolimus and lansoprazole.

CASE SUMMARY

A 34-year-old Japanese man underwent a living-donor kidney transplantation having received tacrolimus, mycophenolate mofetil, and prednisolone for immunosuppression. Lansoprazole was administered from postoperative day 4 as prophylaxis of ulcers. The trough concentration of tacrolimus increased markedly after the introduction of lansoprazole, while results of liver function tests were within normal limits. Lansoprazole was stopped on day 15 and was replaced with famotidine on day 17. The trough concentration of tacrolimus returned to the therapeutic range after administration of lansoprazole ceased. Genetic analysis revealed a heterozygous mutation at exon 5 of the CYP2C19 gene (CYP2C19*1/*2) in this patient.

DISCUSSION

Lansoprazole is metabolized by 2 enzymes, CYP2C19 and CYP3A4. Since tacrolimus is also metabolized by CYP3A4, the blood concentration of tacrolimus in this patient who had a CYP2C19 gene mutation may have been elevated by decreased hepatic elimination of lansoprazole. An objective causality assessment revealed that this interaction was probable.

CONCLUSIONS

Trough concentrations of tacrolimus should be monitored closely for optimizing the dosage regimen in patients receiving concomitant lansoprazole.

Risks of allogeneic hand transplantation

A patient undergoing allogeneic hand transplantation needs lifelong immunosuppression with the risk of serious side effects, including life-threatening disease. The question remains: does the eventual improvement in function justify the risk? To answer this question, we try to assess the risks based on a large body of cumulative data derived from more 200,000 kidney transplants using the Collaborative Transplantation Study (CTS). Only selective data which apply to a patient population aged between 15-40 years were used (n = 58,310). Data are compared to the literature references and show superiority with respect to patient numbers, statistics, actuality, and methodology. The CTS data show that the incidence of de novo malignancies is lower than previously reported. The risk of developing any form of cancer is approximately 3%, of developing a skin cancer 1.1%, and of developing a lymphoma 0.58% within 5 years after transplantation. The risk of suffering from a cataract is 11% after 5 years, which is also lower than previously reported. Although the incidence of side effects (particularly malignant disease) is likely to be lower than previously thought, the risk-benefit question must be answered by each hand surgeon for each individual patient.

Sensitivity of Whole-Blood T Lymphocytes in Individual Patients to Tacrolimus (FK 506): Impact of Interleukin-2 mRNA Expression as Surrogate Measure of Immunosuppressive Effect

Background: To optimize immunosuppressive treatment in individual transplant patients, functional measurements of the effects of tacrolimus (FK 506) are of clinical importance. Previous investigations have demonstrated the occurrence of tacrolimus-resistant production of interleukin-2 (IL-2) in vitro, which may explain in part why rejection episodes are still a frequent problem despite attainment of therapeutic blood concentrations and HLA matching. However, an adequate surrogate marker to define the tacrolimus response in individual patients has not been established.

Methods: We investigated the immunosuppressive effects of tacrolimus on anti-CD3/anti-CD28 T-cell costimulation in a human whole-blood assay, analyzing T-cell proliferation, activation marker expression (CD25, CD69), IL-2 protein expression, and cytokine mRNA expression in vitro (n = 11 healthy individuals). We also quantified IL-2 mRNA expression in patients undergoing tacrolimus (n = 4) or cyclosporin A (CsA; n = 4) monotherapy before ex vivo living-donor kidney transplantation.

Results: T-cell proliferation; CD25, CD69, and IL-2 concentrations; and IL-4 mRNA were significantly decreased in vitro. In contrast, cytokine mRNA profiles revealed variable tacrolimus sensitivity. Whole-blood samples from 3 of 11 healthy individuals demonstrated marked suppression of IL-2 mRNA expression (&gt;50%) when tacrolimus was administered in vitro. When CsA was added to whole-blood cultures, the influence on IL-2 mRNA expression was comparable to that of tacrolimus in 9 of 11 individuals. Two individuals responded conversely, indicating that differences in the in vitro response to tacrolimus and CsA among individuals may be attributable to potential heterogeneity in the involvement of the CD28 pathway. Kinetic profiles of IL-2 mRNA expression also revealed individually distinct degrees of calcineurin inhibitor sensitivity in patients undergoing tacrolimus or CsA monotherapy before living-donor kidney transplantation.

Conclusions: Our results suggest an individual degree of calcineurin inhibitor sensitivity of activated whole-blood lymphocytes based on IL-2 mRNA expression. Our approach is potentially valuable for identifying transplant patients in whom IL-2 mRNA expression is unaffected or even enhanced after initiation of immunosuppressive therapy. Such individuals may be less sensitive to the immunosuppressive agent and therefore at increased risk of transplant rejection. Prospective studies are necessary to determine the correlation of IL-2 mRNA expression with the clinical risk of transplant rejection.

Inhibitors of Calcineurin

Before the early 1980s, patient and allograft survival for solid organ transplant recipients was dismal. By 1983, the first calcineurin blocker, cyclosporine (Sandimmun), had been introduced, and outcomes were dramatically improved. However, cyclosporine macroemulsion had suboptimal pharmacokinetics, significant drug interactions, and several adverse effects, including nephrotoxicity, neurotoxicity, hyperlipidemia, and hypertension. Recent advances with cyclosporine include the introduction of modified dosage formulations: Neoral, a microemulsion, and several generic microemulsion products. The potent second-generation calcineurin blocker tacrolimus (Prograf) was introduced in 1994 and has become the drug of choice for several types of transplant recipients. Although tacrolimus has improved pharmacokinetics and therapeutic drugmonitoring parameters, it has adverse effects such as nephrotoxicity, neurotoxicity, and diabetes. Thus, current immunosuppressive regimens implementing calcineurin blockers often involve additional immunosuppressive agents to “spare” the use of these agents, minimizing their adverse effects. This article reviews the mechanisms of action, pharmacokinetics, clinical use, therapeutic drug monitoring, drug interactions, adverse effects, and dosing of cyclosporine and tacrolimus in solid organ transplant recipients.

Analysis of allograft biopsy specimens from long-term surviving patients with stable renal function: predictive value of long-term graft prognosis

Chronic allograft dysfunction is multi-factorial, and histology of long-term renal allograft shows variable findings. It is important to characterize the pathological features of graft kidneys with normal function to understand the natural course of transplants, which in turn would contribute to elucidate the causes of chronic allograft nephropathy (CAN). To address this issue, we performed 'non-episode' biopsies on well-functioning renal allografts, and evaluated the correlation between clinical outcome and histopathological findings. Patients who underwent a non-episode biopsy had a serum creatinine concentration less than 2.0 mg/dL, urinary protein of less than 500 mg/day and a stable clinical course. In total, 90 such biopsies were performed. Mean follow-up period after biopsy was 29 +/- 16 months. We evaluated the histopathological findings and clinical outcome on each finding. Moreover, we compared the findings in the patients on tacrolimus with those of patients taking cyclosporin. Twenty-three biopsy specimens were essentially normal. Graft dysfunction during the follow-up period was recognized more frequently in patients showing more than one pathological process than in those with isolated findings. Graft outcome was not associated with drug-induced nephropathy, but with acute rejection (P = 0.0193) and CAN (P = 0.0032). Patients found to have CAN-b had a worse outcome than those with CAN-a. CAN-b was less common in the tacrolimus group than in the cyclosporin group. Non-episode biopsy has a predictive value of the long-term outcome of a renal allograft. CAN is associated with graft dysfunction; neither is drug-induced nephropathy. Patients treated with tacrolimus had lower rates of CAN-b than did cyclosporin-treated subjects.

Urinary tract infections after renal transplantation

Up to now one of the major problems for successful organ transplantation has been the reaction of the immune system of the recipient against the donor organ. This could lead to acute and chronic rejection, and in cases of unsuccessful treatment to the loss of the transplant. In organ graft recipients, immunosuppressive agents are used to prevent or treat rejection episodes and to maintain graft function. Although there is an increasing number of immunosuppressive substances, the immunosuppressive therapy currently in use is relatively unspecific and targets many immunological functions. The net state of immunosuppression is a complex function determined by the interaction of a number of factors, the most important of these are the dose, duration and temporal sequence in which immunosuppressive drugs are employed. Any kind of immunosuppressive protocol is thus associated with an increased infection rate. This has an important socioecological impact, because frequent hospitalizations resulting from infectious complications are necessary, having an overall mortality rate of 3.5% within 2 weeks of admission. The most common cause of septicaemia is urinary tract infection. Frequent urinary tract infections are associated with the early onset of chronic rejection, suggesting a pathogenetic relationship between these two features. The occurrence of chronic rejection has led to reduced transplant survival. The prevention of urinary tract infections, or the early diagnosis and accurate treatment of urinary tract infections is important in renal transplant recipients.

Posttransplantation diabetes: a systematic review of the literature

OBJECTIVES

To systematically review the incidence of posttransplantation diabetes (PTD), risk factors for its development, prognostic implications, and optimal management.

RESEARCH DESIGN AND METHODS

We searched databases (MEDLINE, EMBASE, the Cochrane Library, and others) from inception to September 2000, reviewed bibliographies in reports retrieved, contacted transplantation experts, and reviewed specialty journals. Two reviewers independently determined report inclusion (original studies, in all languages, of PTD in adults with no history of diabetes before transplantation), assessed study methods, and extracted data using a standardized form. Meta-regression was used to explain between-study differences in incidence.

RESULTS

Nineteen studies with 3,611 patients were included. The 12-month cumulative incidence of PTD is lower (<10% in most studies) than it was 3 decades ago. The type of immunosuppression explained 74% of the variability in incidence (P = 0.0004). Risk factors were patient age, nonwhite ethnicity, glucocorticoid treatment for rejection, and immunosuppression with high-dose cyclosporine and tacrolimus. PTD was associated with decreased graft and patient survival in earlier studies; later studies showed improved outcomes. Randomized trials of treatment regimens have not been conducted.

CONCLUSIONS

Physicians should consider modification of immunosuppressive regimens to decrease the risk of PTD in high-risk transplant recipients. Randomized trials are needed to evaluate the use of oral glucose-lowering agents in transplant recipients, paying particular attention to interactions with immunosuppressive drugs.

Posttransplant diabetes mellitus in kidney allograft recipients: incidence, risk factors, and management

BACKGROUND

Posttransplant diabetes mellitus (PTDM), associated with the use of immunosuppressants, occurs at varying rates in kidney transplant recipients.

METHODS

Five transplant centers conducted a retrospective review of 435 kidney recipients completing at least 6 months of follow-up to determine risk factors, incidence, and management strategies for posttransplant glucose intolerance. A distinction was made between hyperglycemia and diabetes.

RESULTS

The incidence of PTDM was found to be 4.9%. Among tacrolimus-treated patients it was 5.7%, compared with 3.3% among cyclosporine-treated patients (P=0.453). Mean daily maintenance doses of prednisone and mycophenolate mofetil (MMF) were significantly lower in tacrolimus-treated patients. Significantly more tacrolimus-treated patients were prednisone-free (9.0%/0%; P<0.001). Logistic regression analysis revealed that the absence of an antiproliferative agent correlated with the development of PTDM (odds ratio=3.56; P=0.01).

CONCLUSIONS

Based on this study, we propose management guidelines specifically for glucose intolerance developing after renal transplantation. Maintenance of blood glucose levels within strict limits is recommended, and the contribution of immunosuppressive agents to the development of PTDM is accounted for. Gradual tapering of prednisone and tacrolimus is proposed for patients who develop PTDM but also bear minimal risk of rejection. Tapering and eventual withdrawal of insulin should be attempted once blood glucose levels normalize. Switching to the alternative calcineurin inhibitor should only be considered as a late intervention. Tacrolimus therapy should be considered even in patients at high risk for diabetes, because the benefit of reduced acute rejection incidence and severity, as demonstrated in other studies, outweighs the risk of PTDM.

Posttransplantation diabetes mellitus in FK-506-treated renal transplant recipients: analysis of incidence and risk factors

BACKGROUND

The development of posttransplantation diabetes mellitus has a major impact on the quality of life and long-term outcome.

METHODS

One hundred thirty-nine patients without known glucose metabolism abnormalities and treated with FK-506, methylprednisolone, and mycophenolate mofetil/azathioprine were analyzed for incidence of and risk factors for developing impaired fasting glycemia (IFG) and diabetes mellitus (DM).

RESULTS

Using the American Diabetes Association criteria, 15% developed IFG and 32% developed DM in the first year after transplantation. High trough levels of FK-506 during the first month after transplantation (especially >15 ng/ml) and high body mass index (BMI) were significant risk factors for IFG or DM. Patients with (steroid-treated) acute rejections in addition to high trough levels of FK-506 were most prone to develop DM, whereas high BMI conferred risk of developing IFG. Patients with posttransplantation glycemic abnormalities also had higher levels of serum triglycerides at the time of transplantation, but they needed a lower dose of FK-506 to obtain higher trough levels of FK-506, suggesting metabolic differences already present before transplantation. The only risk factor retained for persistent IFG or DM beyond the first year was a higher number of trough levels of FK-506 >15 ng/ml during the first month after transplantation.

CONCLUSIONS

Induction with an FK-506 based immunosuppressive regimen resulted in a high incidence of glucose metabolism disorders in renal transplantation recipients. Higher trough levels of FK-506 during the first month, acute rejections, and higher BMI were the most obvious risk factors.

Oral health in liver transplant children administered cyclosporin A or tacrolimus

BACKGROUND

Immunosuppression by cyclosporin A (CsA) is associated with adverse side-effects, including nephrotoxicity, neurotoxicity and gingival overgrowth. Tacrolimus (TAC/FK506) is a new immunosuppressive agent, recently approved for use in solid-organ transplants. The mode of action of TAC is similar to that of CsA and the toxicity profile of CsA is duplicated by TAC. The effect of TAC on the gingival tissue is not yet conclusive.

SAMPLE

Gingival overgrowth was assessed in 30 liver transplant children, 20 boys and 10 girls, aged 2-19 years. Seventeen children (10 boys, seven girls) were on a CsA-based immunosuppressive regimen whereas 13 children (10 boys, three girls) were on TAC for at least 1 year (mean 4.3 +/- 2.7).

RESULTS

In the CsA group, 35% of children exhibited gingival overgrowth characterized by one or more units with increased sulcus probing depth (> or = 4 mm), i.e. pseudopockets. In contrast to the CsA group, none of the children in the TAC group exhibited gingival overgrowth. The occurrence of enamel hypoplasia was observed in 11 children (36%) and enamel opacities were found in 23 children (76%). Six of the 12 children (50%) with hyperbilirubinaemia biliary atresia exhibited a marked greenish discoloration of the teeth. Caries experience (dmft/DMFT) among these children was 2.0 +/- 2.8.

CONCLUSION

No difference in caries experience or enamel defect was observed between the CsA and TAC group.

Effective oral administration of tacrolimus in renal transplant recipients

BACKGROUND

Tacrolimus is usually administered orally based on mg/kg or the trough concentration (Cmin) in whole blood. However, it is not easy to determine the optimal oral dose because of considerable variation of tacrolimus bioavailability between patients. In this study, pharmacokinetics of tacrolimus in various conditioning kidney transplant recipients was investigated.

METHODS

1) Thirty-three patients were randomly assigned to participate in two groups. In 17 patients, tacrolimus was administered orally after an overnight fast with breakfast given 1 h later, and in the other 16 patients it was administered orally 1 h after breakfast. 2) In 4 patients, the same dose tacrolimus was given after an overnight fast and 0.5 h after breakfast on two consecutive days. 3) Five patients who underwent continuous ambulatory peritoneal dialysis (CAPD) before transplantation were studied. All patients were investigated in daily profile of tacrolimus blood levels.

RESULTS

There was a strong correlation between area under the curve (AUC) and the trough concentration in both preprandial and postprandial oral administration, with correlation coefficients of 0.838 and 0.860, respectively. Significant increases in the peak concentration (Cmax) and AUC were observed in the preprandial oral administration subjects. Absorption of CAPD patients was obviously insufficient.

CONCLUSIONS

Since tacrolimus absorption was better under fasted condition than under the presence of food, it is thought that the highest medicine effect with the least dosage is provided by preprandial oral administration. Furthermore, preprandial oral administration is recommended from a respect of economic burden reduction and side effect reduction.

Dose optimization of mycophenolate mofetil when administered with a low dose of tacrolimus in cadaveric renal transplant recipients

BACKGROUND

Supplementation of immunosuppressive therapy with mycophenolate mofetil (MMF) has been found to reduce the rate of acute rejection in renal transplantation. We report a dose-finding study for MMF when administered in combination with low-dose tacrolimus and corticosteroid prophylaxis in cadaveric renal transplant recipients.

METHODS

Two hundred thirty-two patients at 16 centers were enrolled in this randomized, parallel-group study. The three treatment groups were tacrolimus and corticosteroids (MMF-0 group, n=82); tacrolimus, corticosteroids, and 1 g of MMF daily (MMF-1 g group, n=79); and tacrolimus, corticosteroids, and 2 g of MMF daily (MMF-2 g group, n=71). Study duration was 6 months, and patients were followed up for patient and graft survival for 12 months.

RESULTS

At 6 months posttransplantation, daily doses of 1 g and 2 g of MMF were associated with significantly lower rates of acute rejection compared with tacrolimus alone. The Kaplan-Meier rates were 48.5%, 24.9%, and 22.9%, respectively, for the three treatment groups when acute rejection was determined by clinical criteria (P=0.007). At month 12, patient survival rates were 100%, 97.5%, and 97.2% and graft survival rates were 90.2%, 92.4%, and 93.0% for the MMF-0 group, MMF-1 g group, and the MMF-2 g group, respectively. Gastrointestinal adverse events and leukopenia were higher in the MMF groups, especially in the MMF-2 g group (P<0.05).

CONCLUSIONS

Low-dose tacrolimus combined with a MMF dose of 1 g daily and corticosteroids provided an optimized efficacy and safety profile. A higher dose of MMF (2 g) was associated with greater toxicity without a significant improvement in efficacy.

An analysis of early renal transplant protocol biopsies--the high incidence of subclinical tubulitis

To investigate the possibility that we have been underestimating the true incidence of acute rejection, we began to perform protocol biopsies after kidney transplantation. This analysis looks at the one-week biopsies. Between March 1 and October 1, 1999, 100 adult patients undergoing cadaveric kidney or kidney/pancreas transplantation, or living donor kidney transplantation, underwent 277 biopsies. We focused on the subset of biopsies in patients without delayed graft function (DGF) and with stable or improving renal function, who underwent a biopsy 8.2+/-2.6 d (range 3-18 d) after transplantation (n = 28). Six (21%) patients with no DGF and with stable or improving renal function had borderline histopathology, and 7 (25%) had acute tubulitis on the one-week biopsy. Of the 277 kidney biopsies, there was one (0.4%) serious hemorrhagic complication, in a patient receiving low molecular weight heparin; she ultimately recovered and has normal renal function. Her biopsy showed Banff 1B tubulitis. In patients with stable or improving renal allograft function early after transplantation, subclinical tubulitis may be present in a substantial number of patients. This suggests that the true incidence of rejection may be higher than is clinically appreciated.

Recommendations for the outpatient surveillance of renal transplant recipients. American Society of Transplantation

Many complications after renal transplantation can be prevented if they are detected early. Guidelines have been developed for the prevention of diseases in the general population, but there are no comprehensive guidelines for the prevention of diseases and complications after renal transplantation. Therefore, the Clinical Practice Guidelines Committee of the American Society of Transplantation developed these guidelines to help physicians and other health care workers provide optimal care for renal transplant recipients. The guidelines are also intended to indirectly help patients receive the access to care that they need to ensure long-term allograft survival, by attempting to systematically define what that care encompasses. The guidelines are applicable to all adult and pediatric renal transplant recipients, and they cover the outpatient screening for and prevention of diseases and complications that commonly occur after renal transplantation. They do not cover the diagnosis and treatment of diseases and complications after they become manifest, and they do not cover the pretransplant evaluation of renal transplant candidates. The guidelines are comprehensive, but they do not pretend to cover every aspect of care. As much as possible, the guidelines are evidence-based, and each recommendation has been given a subjective grade to indicate the strength of evidence that supports the recommendation. It is hoped that these guidelines will provide a framework for additional discussion and research that will improve the care of renal transplant recipients.

Conversion from tacrolimus to cyclosporine in stable renal transplant patients: safety, metabolic changes, and pharmacokinetic comparison

BACKGROUND

Although conversion between tacrolimus and cyclosporine has been performed when indicated for rejection or adverse effects, the safety and metabolic outcome of elective conversion from tacrolimus to cyclosporine has not previously been examined.

METHODS

Conversion from tacrolimus to cyclosporine was performed in 19 recipients of cadaver renal transplants at 3-6 months after transplantation. Pharmacokinetic profiles and biochemical studies were performed three times, in steady state, before, and after conversion.

RESULTS

Patient and graft survival was 100% at 3 months after conversion, with no rejection episodes. Three patients have been subsequently converted back to tacrolimus, two for rejection and one for hirsutism. There were no significant changes in creatinine, urate, or blood sugar levels after conversion, but the mean plasma magnesium rose from 0.73 (0.63-0.97) to 0.82 (0.65-1) mmol/L (P=0.037), and the mean plasma cholesterol rose from 5.2 (3.4-6.8) to 5.5 (3.8-7.6) mmol/L (P=0.033). Pharmacokinetic profiles were measured before and after conversion, and showed that cyclosporine (Neoral) exhibited significantly less interpatient and intrapatient variability than tacrolimus, for area under the curve (AUC), maximum concentration after dose (Cmax), minimum concentration after dose (Cmin), and time to maximum concentration (Tmax).

CONCLUSION

This is the first study that has examined the outcome of conversion from tacrolimus- to cyclosporine-based immunosuppression in stable patients after renal transplantation. This conversion was performed without early immunological hazard, but there was a small rise in blood cholesterol levels after conversion. Pharmacokinetic studies showed that cyclosporine in the form of Neoral exhibited less inter- and intrapatient variability than tacrolimus, although this is of uncertain clinical significance.

Immunosuppression in older renal transplant patients

Renal transplantation procedures in patients older than 60 years of age have clearly improved in recent years. In the cyclosporin era, graft and patient survival are good. However, older patients exhibit a higher mortality, especially from infectious and cardiovascular causes, than young patients. In this article we review the immunosuppressive treatment in older patients, analyse what drugs can be used and finally propose several immunosuppressive combinations to treat this group of patients. Currently, new immunosuppressive drugs enable more flexible immunosuppressive protocols. Nevertheless, to avoid overimmunosuppression, elderly patients should be treated with lower doses and fewer immunosuppressive drugs.

Results of pancreas transplantation after steroid withdrawal under tacrolimus immunosuppression

PURPOSE

The results of steroid withdrawal in pancreas transplant recipients under tacrolimus immunosuppression were analyzed.

METHODS

From July 4, 1994 until April 30, 1998, 147 pancreas transplantations were performed in 141 patients, including 126 simultaneous pancreas-kidney transplantations, 13 pancreas after kidney transplantation, and 8 pancreas transplantations alone. Baseline immunosuppression consisted of tacrolimus and steroids without antilymphocyte induction. Twenty-three patients were excluded from analysis because of early graft loss in 17 cases, retransplantation in 5 cases, and simultaneous pancreas-kidney transplantation after heart transplantation in 1 patient.

RESULTS

With a mean follow-up of 2.8+/-1.1 years (range 1.0 to 4.8 years), complete steroid withdrawal was achieved in 58 (47%) patients with a mean time to steroid withdrawal of 15.2+/-8 months (range 4 to 40 months after transplantation). Of the entire cohort of 141 patients, overall 1-, 2-, and 4-year patient survival rates were 98%, 95.5%, and 86%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 83%, 80%, and 71% (pancreas) and 95%, 91%, and 84% (kidney), respectively. Of the 124 patients analyzed for steroid withdrawal, 1-, 2-, and 4-year patient survival rates were 98%, 97%, and 92%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 98%, 91.5%, 83% (pancreas) and 97%, 95%, and 91% (kidney). Patient, pancreas, and kidney survival rates at 1 year were 100%, 100%, and 98% (off steroids) versus 97%, 91%, and 96% (on steroids, all NS) and at 4 years were 100%, 94%, and 95% (off steroids) versus 78%, 68%, and 85% (on steroids, P = 0.01, 0.002, and NS, respectively). The cumulative risk of rejection at the time of follow-up was 76% for patients on steroids versus 74% for patients off steroids (P = NS). Seven patients originally tapered off steroids were treated for subsequent rejection episodes, which were all steroid sensitive, and two of these seven patients are currently off steroids. Thirteen patients received antilymphocyte therapy for steroid-resistant rejection, five of whom are now off steroids. Tacrolimus trough levels were 9.3+/-2.4 ng/ml (off steroids) and 9.7+/-4.3 (on steroids, P = NS). Mean fasting glucose levels were 98+/-34 mg/dl (off steroids) and 110+/-41 mg/dl (on steroids, P = NS). Mean glycosylated hemoglobin levels were 5.2+/-0.9% (off steroids) and 6.2+/-2.1% (on steroids, P = 0.02), and mean serum creatinine levels were 1.4+/-0.8 mg/dl (off steroids) and 1.7+/-1.0 mg/dl (on steroids, P = 0.02).

CONCLUSION

These data show for the first time that steroid withdrawal can be safely accomplished in pancreas transplant recipients maintained on tacrolimus-based immunosuppression. Steroid withdrawal is associated with excellent patient and graft survival with no increase in the cumulative risk of rejection.

Posttransplant lymphoproliferative disorders in adult and pediatric renal transplant patients receiving tacrolimus-based immunosuppression

Between March 27, 1989 and December 31, 1997, 1316 kidney transplantations alone were performed under tacrolimus-based immunosuppression at our center. Posttransplant lymphoproliferative disorders (PTLD) developed in 25 (1.9%) cases; the incidence in adults was 1.2% (15/1217), whereas in pediatric patients it was 10.1% (10/99; P<.0001). PTLD was diagnosed 21.0+/-22.5 months after transplantation, 25.0+/-24.7 months in adults and 14.4+/-18.2 months in pediatric patients. Of the 4 adult cases in whom both the donor and recipient Epstein Barr virus (EBV) serologies were known, 2 (50%) were seropositive donor --> seronegative recipient. Of 7 pediatric cases in whom both the donor and recipient EBV serologies were known, 6 (86%) were EBV seropositive donor --> seronegative recipient. Acute rejection was observed before the diagnosis of PTLD in 8 (53%) of 15 adults and 3 (30%) of 10 pediatric patients. Initial treatment of PTLD included a marked decrease or cessation of immunosuppression with concomitant ganciclovir therapy; two adults and two pediatric patients required chemotherapy. With a mean follow-up of 24.9+/-30.1 months after transplantation, the 1- and 5-year actuarial patient and graft survival rates in adults were 93% and 86%, and 80% and 60%, respectively. Two adults died, 3.7 and 46.2 months after transplantation, of complications related to PTLD, and 10 (including the 2 deaths) lost their allograft 3.7-84.7 months after transplantation. In children, the 1- and 5-year actuarial patient and graft survival rates were 100% and 100%, and 100% and 89%, respectively. No child died; one child lost his allograft 41.3 months after transplantation. One child had presumed recurrent PTLD that responded to discontinuation of tacrolimus and reinitiation of antiviral therapy. The mean serum creatinine level in adults was 2.5+/-1.2 mg/dl, and in children, it was 1.3+/-0.6 mg/ dl. Under tacrolimus-based immunosuppression, PTLD is less common after renal transplantation in adults than in children, but PTLD in children is associated with more favorable outcomes than in adults.

Use of tacrolimus in renal transplantation

Tacrolimus is a very potent drug for preventing all types of acute rejection after renal transplantation. The decrease of vascular rejection may have important long-term implications. This is demonstrated in the 3-year data of the U.S. multicentre trial, where a significant decrease of graft loss was observed in the tacrolimus patients compared to cyclosporine patients. Safety profiles of both drugs are the same, but there are some major differences in side effects. Hyperglycemia is more common during tacrolimus, but generally the induction of hyperglycemia is a dose-dependent reversible process, which leads generally to diabetes mellitus during high systemic exposure, in certain races and prediabetics. Gum hyperplasia and hirsutism are not seen during tacrolimus therapy and there is a more favorable cardiovascular risk profile during tacrolimus as compared to cyclosporine based immunosuppression.

A prospective, randomized trial of tacrolimus/prednisone versus tacrolimus/prednisone/mycophenolate mofetil in renal transplant recipients

BACKGROUND

Between September 20, 1995 and September 20, 1997, 208 adult patients undergoing renal transplantation were randomized to receive tacrolimus/prednisone (n=106) or tacrolimus/prednisone/mycophenolate mofetil (n=102), with the goal of reducing the incidence of rejection.

METHODS

The mean recipient age was 50.7+/-13.7 years. Sixty-three (30.3%) patients were 60 years of age or older at the time of transplantation. The mean donor age was 34.5+/-21.7 years. The mean cold ischemia time was 30.5+/-9.2 hr. The mean follow-up is 15+/-7 months.

RESULTS

The overall 1-year actuarial patient survival was 94%; the overall 1-year actuarial graft survival was 87%. When the patient and graft survival data were stratified to recipients under the age of 60 who did not have delayed graft function, the overall 1-year actuarial patient survival was 97%, and the corresponding 1-year actuarial graft survival was 93%. There were no differences between the two groups. The overall incidence of rejection was 36%; in the double-therapy group, it was 44%, whereas in the triple therapy group, it was 27% (P=0.014). The mean serum creatinine was 1.6+/-0.8 mg/dl. A total of 36% of the successfully transplanted patients were taken off prednisone; 32% of the patients were taken off antihypertensive medications. The incidence of delayed graft function was 21%, the incidence of cytomegalovirus was 12.5%, and the initial and final incidences of posttransplant insulin-dependent diabetes mellitus were 7.0% and 2.9%; again, there was no difference between the two groups.

CONCLUSIONS

This trial suggests that the combination of tacrolimus, steroids, and mycophenolate mofetil is associated with excellent patient and graft survival and a lower incidence of rejection than the combination of tacrolimus and steroids.