Immediate and long-term results of ATG induction therapy for delayed graft function compared to conventional therapy for immediate graft function

A CD3+ count-based thymoglobulin induction regimen permits delayed introduction of calcineurin inhibitors in kidney transplantation

BACKGROUND

Withholding calcineurin inhibitors (CNIs) can be considered when graft function is inadequate following kidney transplantation (KT). Thymoglobulin (rATG) can be used to prevent acute rejection while CNIs are being withheld. Here, we report our results of a novel CNI-sparing induction protocol, which utilizes a CD3+ cell count-based rATG treatment regimen when delayed graft function (DGF) develops in the immediate postoperative period.

METHODS

In a cohort of 153 consecutive deceased-donor KT recipients, all received a single intraoperative dose of basiliximab; 84 subsequently developed DGF and therefore received rATG (rATG+ group), while 69 demonstrated immediate graft function and received CNIs (rATG- group).

RESULTS

In the rATG+ group, mean duration of therapy was 8.5±6.0 d, permitting CNI initiation to be delayed until postoperative day 10.3±6.2. Cumulative dose of rATG was only 5.1±4.5 mg/kg while targeting CD3+ counts of ≤30 cells/mm3. CD3+ counts were reduced to a mean of 16.7±17.0 cells/mm3 during therapy. At one yr, patient and graft survival rates were 97.6% and 92.9%, respectively, while the frequency of infections and malignancies were not significantly increased compared to the rATG- group.

CONCLUSION

A unique induction regimen successfully delayed CNI initiation by using modest doses of rATG to deplete CD3+ cells, while yielding excellent long-term graft outcome without increased risk of infection or malignancy.

Evolving trends in induction therapy

A decade of spectacular innovation in maintenance immunosuppressive drugs has resulted in dramatic reductions in acute rejection and improvement in short- and long-term outcomes after renal transplantation. However, the new drugs continue to lack specificity, many require frequent therapeutic drug monitoring, and all of them are associated with acute and chronic toxicities. The new biologic agents, monoclonal antibodies, and receptor-fusion proteins lack immunogenicity, have long half-life and prolonged biologic effects, require intermittent administration, and have minimal toxicity. The specificity and selectively of the targets of the new biologic agents render them less toxic than the oral maintenance drugs and thus could possibly replace those drugs most frequently associated with long-term toxicity such as the corticosteroids and the calcineurin inhibitors.

Randomized trial of single-dose versus divided-dose rabbit anti-thymocyte globulin induction in renal transplantation: an interim report

BACKGROUND

The optimal dosing protocol for rabbit anti-thymocyte globulin (rATG) induction in renal transplantation has not been determined, but evidence exists that rATG infusion before renal allograft reperfusion improves early graft function. Infusing a large rATG dose over a short interval has not previously been evaluated for its effect on renal function and allograft nephropathy in a prospective, randomized comparison against conventional rATG induction.

METHODS

Between April 20, 2004 and December 26, 2007 we enrolled renal transplant patients into a prospective, randomized, nonblinded trial of two rATG dosing protocols (single dose, 6 mg/kg vs. divided doses, 1.5 mg/kg every other day x 4; target enrollment=160) followed after 6 months by calcineurin-inhibitor withdrawal. Primary endpoints are renal function by calculated glomerular filtration rate (GFR) and chronic allograft nephropathy at protocol biopsy. We now present the early GFR data of all 160 patients and safety and efficacy data of the first 142 patients with 6 months follow up and before calcineurin inhibitor withdrawal (average follow up=23.3+/-11.6 months).

RESULTS

There were no differences between groups in rATG-related adverse events, patient and graft survival, acute rejection, or chronic allograft nephropathy rate at 6 months. Calculated DeltaGFR (POD 1-4) was significantly better in the single-dose group (P=0.02), with a trend toward improved renal function from months 2 to 6 in recipients of deceased donor kidneys (P=0.08).

CONCLUSIONS

This study demonstrates that administering 6 mg/kg of rATG over 24 hr is safe and is associated with improved early renal function compared with administering rATG in alternate-day doses.

Effect of prophylaxis with low-dose anti-thymocyte globulin on prevention of acute kidney allograft rejection

INTRODUCTION

During kidney transplantation, the first contact between the recipient's immune system and the donor organ takes place immediately following the arterial anastomosis. The aim of this study was to evaluate the efficacy of a single, low-dose anti-thymocyte globulin (ATG) prophylaxis in the reduction of early acute rejection in renal allograft recipients.

METHODS

In a randomized, controlled clinical trial, we studied the rate of acute rejection within the first month of kidney transplantation in patients who had received their transplant at a single center between the years 2004 and 2007. The patients were divided into 2 groups: group 1 (n = 37) received cyclosporine, mycophenolate mofetil or azathioprine, and prednisolone; group 2 (n = 31) received the above-mentioned agents plus a single ATG bolus (Thymoglobulin; SangStat, Lyon, France; 4-5 mg/kg) the night before the transplantation ( approximately 12 hours before the operation). Blood urea and serum creatinine levels were measured regularly in the posttransplantation period. Acute allograft rejection was justified clinically and/or pathologically. Statistical analysis was performed by SPSS 13.0 using Student t test and Fisher exact test. A P value < or = .05 was considered to indicate statistical significance.

RESULTS

There were no significant differences regarding the age and gender ratio between the 2 groups. Acute allograft rejection was found in 32.4% (n = 12) of group 1 patients, and was reduced to 12.9% (n = 4) in group 2 (P = .05). Hence, the first-month acute rejection episodes decreased by approximately 60% with ATG prophylaxis in renal transplant recipients.

CONCLUSION

Prophylactic administration of a single and low-dose ATG the night before kidney transplantation could reduce the risk of acute allograft rejection in renal transplant recipients. However, further studies with a greater number of patients should be conducted to confirm these results.

Selective unresponsiveness to beta cell autoantigens after induction immunosuppression in pancreas transplantation with anti-interleukin-2 receptor antibody versus anti-thymocyte globulin

Pancreas transplantation in type 1 diabetes patients could result in (re)activation of allo- and autoreactive T lymphocytes. Anti-thymocyte globulin (ATG) induction treatment is a successful, but broadly reactive anti-lymphocyte therapy used in pancreas and islet transplantation. A more selective alternative is daclizumab, a monoclonal antibody directed against the interleukin-2 receptor (CD25) on activated lymphocytes. We tested the hypothesis that daclizumab is more selective and has less immunological side effects than ATG. Thirty-nine simultaneous pancreas-kidney transplantation patients with type 1 diabetes were randomized for induction therapy with ATG or daclizumab. Auto- and recall immunity was measured cross-sectionally by lymphocyte stimulation tests with a series of auto- and recall antigens in 35 successfully transplanted patients. T cell autoimmunity to islets was low in both groups, except for a marginal but significantly higher reactivity against glutamic acid decarboxylase (GAD)65 in daclizumab-treated patients. The memory responses to recall antigens were significantly higher in the daclizumab-treated group compared to ATG-treated patients, specifically against purified protein derivative (PPD) (anti-bacterial immunity), Haemophilus influenzae virus matrix protein-1 (anti-viral immunity) and p53 [anti-tumour (auto)immunity]. These data imply that daclizumab is more specifically affecting diabetes-related immune responses than ATG. The autoimmunity is affected effectively after daclizumab induction, while memory responses towards bacterial, viral and tumour antigens are preserved.

Polyclonal Antibodies in Renal Transplantation—A Relook

Polyclonal antibodies have been used in renal transplantation for the past four decades. Increasing knowledge regarding their varied mechanisms of action have confirmed their versatility in clinical practice. They can be used for induction, reversing acute rejections (especially those resistant to steroids), and possibly conferring an element of allotolerance, thereby reducing chronic allograft nephropathy. Their recent usage as IV bolus, single-dose, preoperative infusion as induction therapy in renal transplantation is an attractive and extremely cost-effective strategy, especially in a developing country such as India.

One Year Results of Preoperative Single Bolus ATG-Fresenius Induction Therapy in Sensitized Renal Transplant Recipients

Sensitization in kidney transplantation is associated with more acute rejections, inferior graft survival, and an increase in delayed graft function. This study was designed to evaluate the efficacy and safety of preoperative single bolus antithymocyte globulin (ATG) induction therapy in sensitized renal transplant recipients.

METHODS

Fifty-six cadaveric donor kidney transplant recipients were divided into two groups: Group I (nonsensitized group, n = 30) and group II (sensitized group, PRA>10%, n = 26). ATG was given as a single preoperative bolus induction therapy to group II (ATG IV; 9 mg/kg). The group I patients were treated with mycophenolate mofetil preoperatively as induction therapy. The basic immunosuppressive regimen included tacrolimus (FK-506) or cyclosporine, mycophenolate mofetil, and prednisolone. After hospital discharge, patients were followed on a routine outpatient basis for 12 months.

RESULTS

Acute rejection episodes (ARE) occurred in 20% (6/30) of group I and 15.38% (4/26) of group II patients (P = NS). Infections occurred in eight patients (26.7%) as 11 episodes (36.7%), averaging 1.4 episodes per infected patient in group 1, and 6 patients (23.1%) for a total of 10 episodes (38.5%), averaging 1.7 episodes per infected patient, in group II (P = NS). Occurrence of side effects and hospital stay were almost comparable in the two groups. No delayed graft function was observed in either group. The 12-month actuarial patient and graft survival were 100% in Group I and II.

CONCLUSION

A preoperative single bolus ATG induction therapy was an effective and safe therapeutic measure, yielding an acceptable acute rejection rate in presensitized renal transplant recipients.

Impact of early or delayed cyclosporine on delayed graft function in renal transplant recipients: a randomized, multicenter study

The benefit of delayed cyclosporine in reducing risk of delayed graft function (DGF) is not clearly established. This study compared early vs. delayed cyclosporine microemulsion (CsA-ME) inde novorenal transplant patients. Patients were randomized to early (day 0, n=97) or delayed (day 6, n=100) CsA-ME at an initial dose of 8 mg/kg/day with dose adjusted according to C2 level. All patients received enteric-coated mycophenolate sodium (EC-MPS), steroids and an anti-interleukin-2 receptor antibody. In both groups, 33% of patients were at high risk of DGF; 26 patients (26.8%) in the early CsA-ME group and 23 patients (23.0%) in the delayed CsA-ME group experienced DGF (n.s.). Renal function at 3 months was comparable (creatinine clearance 51.1 mL/min with early CsA-ME and 53.8 mL/min with delayed CsA-ME), and remained similar to 12 months. Treatment failure, defined as biopsy-proven acute rejection, graft loss or death, did not differ significantly at 12 months (23.7% with early CsA-ME vs. 29.0% with delayed CsA-ME). Biopsy-proven acute rejection occurred in 15.5% of early CsA-ME and 26.5% of delayed CsA-ME patients (n.s.). Both regimens were well tolerated. These data suggest that early or delayed introduction of CsA-ME results in similar renal function in renal transplant patients regardless of DGF risk level.

TCR stimulation with modified anti-CD3 mAb expands CD8+ T cell population and induces CD8+CD25+ Tregs

Modified anti-CD3 mAbs are emerging as a possible means of inducing immunologic tolerance in settings including transplantation and autoimmunity such as in type 1 diabetes. In a trial of a modified anti-CD3 mAb [hOKT3gamma1(Ala-Ala)] in patients with type 1 diabetes, we identified clinical responders by an increase in the number of peripheral blood CD8+ cells following treatment with the mAb. Here we show that the anti-CD3 mAb caused activation of CD8+ T cells that was similar in vitro and in vivo and induced regulatory CD8+CD25+ T cells. These cells inhibited the responses of CD4+ cells to the mAb itself and to antigen. The regulatory CD8+CD25+ cells were CTLA4 and Foxp3 and required contact for inhibition. Foxp3 was also induced on CD8+ T cells in patients during mAb treatment, which suggests a potential mechanism of the anti-CD3 mAb immune modulatory effects involving induction of a subset of regulatory CD8+ T cells.

Assessment of two strategies of neoral administration, early versus delayed, on renal function and efficacy in de novo renal transplant patients receiving myfortic, steroids, and anti-IL2R antibodies: 12-month results of a randomized, multicentre, open, prospective controlled study

The optimal immunosuppressive strategy and benefit of delaying Neoral to prevent delayed graft function (DGF) have not been clearly established. Renal function was assessed by estimated creatinine clearance (Cockcroft-Gault) at 3 months, and efficacy by treatment failure and BPAR at 6 and 12 months after renal transplantation. Two hundred three patients were enrolled after stratification according to DGF risk (USRDS criteria). One hundred ninety-seven were randomized to receive either early (E; day 0; n = 97) or delayed (D; day 6; n = 100) Neoral in combination with myfortic, steroids, and anti-IL2R antibodies. Neoral was adjusted using C2. Six patients who were not randomized have been excluded from the intention-to-treat (ITT) analysis.

RESULTS

There was no significant difference in the demographic or baseline parameters between the two groups. The risk of DGF(score > or = 5) was similar in both groups: 32 of 97 in E-Neoral versus 33 of 100 in D-Neoral. In the group at high risk for DGF, the incidence of DGF was 13 of 32 pts in E-Neoral versus 14 of 33 in D-Neoral. Renal function was not statistically different between the two groups in both the ITT and per-protocol (PP) populations at 3, 6, or 12 months. Over 12 months, the evidence of treatment failure and BPAR were not statistically different: 24 of 97 (24.7%) versus 27 of 100 (27%) and 18 of 97 (18.6%) versus 24 of 100 (24%) for E-Neoral and D-Neoral, respectively. The severity of acute rejection was mild in 83% patients.

CONCLUSION

These data suggest that there is no significant impact on renal function and immunosuppressing efficacy of early versus delayed introduction of Neoral, in combination with myfortic and steroids among renal transplant patients with or without a risk of DGF.

Evaluation of daclizumab to reduce delayed graft function in non-heart-beating renal transplantation: a prospective, randomized trial

Daclizumab (DZB), an interleukin-2 receptor blocker, has been shown to reduce the rate of acute rejection, while non-heart-beating kidney recipients have high rates of delayed graft function that may be prolonged by high levels of calcineurin inhibitors. This study assessed whether DZB could safely replace calcineurin inhibitors in the immediate postoperative period and promote recovery from ischemic acute tubular necrosis. Patients were randomized into one of two groups: DZB induction and daily mycophenolate mofetil (MMF; 2 g) with steroids (20 mg prednisone) or standard triple therapy with tacrolimus, MMF, and prednisone. Patients in the DZB arm were converted to the control arm when either the serum creatinine dropped to <350 micromol/L or there was biopsy evidence of acute rejection. Over 2 years, Leicester and Newcastle non-heart-beating donor (NHBD) centers recruited 51 patients. There was one patient death in the DZB arm, during the study period, after a nonfunctioning graft was removed. A total of two (8%) grafts in the DZB arm and three (11.5%) grafts in the control arm failed to function. The overall rate of immediate function improved from around 5% (pre-2001) to 28%. There were no significant differences in the incidence of acute rejection or graft function (GFR) at 3 months. Machine-perfused kidneys in DZB-treated recipients had the highest rates of immediate function (53%, P = .015). We found that a calcineurin-sparing regime is safe and may be beneficial for recipients of machine-perfused grafts damaged by warm ischemia.

Immunosuppression With Antithymocyte Globulin in Renal Transplantation: Better Long-Term Graft Survival

We analyzed the impact of antithymocyte globulin (ATG) in renal transplantation. We retrospectively studied 1217 recipients performed from July 83 to December 03. ATG-Fresenius-S (ATG-F) was used for induction therapy in 492 patients (40.4%; group I) and compared with group II, 725 patients (59.6%), without antilymphocyte induction. Groups were comparable in terms of recipient gender and race distribution; time on dialysis; cause of renal disease; number of human leukocyte antigen (HLA) mismatches; donor age, gender, and creatinine; and cold ischemia time. Patients with ATG-F were younger (35.8 +/- 13.8 vs 38.9 +/- 12.5 years, P < .001), more frequently hypersensitized (10% vs 3%, P < .001), and had more second transplants (15.7% vs 5.8%, P < .001). The incidence of acute rejection episodes was lower among ATG-F patients (23.6% vs 32.1%, P = .004). Admission time and incidence of delayed graft function (DGF) were similar in the two groups. Graft survival at 1, 5, 10, and 15 years was 88.9%, 80.7%, 71.3%, and 64.9% in group I and 86.4%, 77.4%, 60.7%, and 48.4% in group II (P = .003). The difference in patient survival over the same follow-up did not reach statistical significance. Multivariate analysis showed that the risk of graft failure was higher for those who did not receive ATG-F (HR = 1.51; 95% CI, 1.14 to 2.00; P = .004). Donor age and DGF were also independent predictors of graft failure. Our results showed a better long-term graft survival among patients who received ATG-F, despite their higher immunological risk. The absence of induction with ATG-F, donor age, and DGF were independent risk factors for graft failure.

Randomized clinical trial of daclizumab induction and delayed introduction of tacrolimus for recipients of non-heart-beating kidney transplants

Background

Kidneys from non-heart-beating donors (NHBDs) have high rates of delayed graft function (DGF). Use of calcineurin inhibitors is associated with a reduction in renal blood flow, which may delay graft recovery from ischaemic acute tubular necrosis.

Methods

To assess whether daclizumab (DZB) could safely replace tacrolimus in the immediate postoperative period, patients were randomized to receive DZB induction and daily mycophenolate mofetil with steroids (DZB group) or standard tacrolimus-based triple therapy (control group). Tacrolimus was given to patients in the DZB group when the serum creatinine level dropped below 350 µmol/l.

Results

Fifty-one patients were recruited at two centres over a 2-year interval between 2000 and 2003. The overall rate of immediate function was 28 per cent (13 of 46 grafts), with the highest rate in recipients of machine-perfused kidneys treated with DZB (eight of 15 patients).

Conclusion

Induction with DZB and delayed introduction of tacrolimus reduced the incidence of DGF in recipients of machine-perfused NHBD kidneys.

Beneficial effect of concomitant induction with antilymphoblast globulin, cyclosporine, and steroids on long-term renal allograft outcome

BACKGROUND

The addition of induction therapy with antilymphocytic antibodies to cyclosporine (CsA) based immunosuppression, has reduced acute rejection incidence and improved short-term survivals, but has not had well-established effects on long-term renal transplant survival.

PATIENTS

We analyzed the long-term allograft outcome of patients included in a prospective randomized clinical study conducted in our center 15 years ago by comparing two strategies: (A) horse antilymphoblast globulin (ALG) given at 10 mg/kg on alternate days to a maximum of 6 doses with low-dose CsA started at 8 mg/kg per day and prednisone at 0.25 mg/kg per day, versus (B) CsA started at 15 mg/kg per day and prednisone at 0.5 mg/kg per day. Diabetic and highly sensitized patients (PRA > 70%) were excluded from the study.

RESULTS

The characteristics of the 50 patients enrolled in each group were not different. Although patient survival was not different (88% in group A vs 77% in group B), recipients treated with ALG showed a lower incidence of acute rejection episodes (20% vs 44%, P = .01) and better death-censored renal allograft survival (57% vs 41%, P = .03). Among rejection-free patients, graft survival was 15% higher in group A (60% vs 45%, P = .12). Multivariate Cox regression analysis showed that an acute rejection episode (relative risk [RR]: 2.44, 95% confidence interval [CI] 1.36-4.39; P = .0029) rather than ALG immunosuppression (RR 0.74, 95% CI 0.41-1.33; P = NS) was an independent predictor of death-censored graft survival.

CONCLUSIONS

In summary, we confirmed that concomitant induction therapy with ALG, CsA, and steroids improves long-term renal allograft survival.

Effect of mycophenolate mofetil on kidney graft function and body weight in patients with chronic allograft nephropathy

BACKGROUND

Chronic allograft nephropathy (CAN) is the most common cause of late graft loss. A beneficial effect of mycophenolate mofetil (MMF) on CAN was observed, although, due to the loss of body weight (BW) under MMF, serum creatinine (sCr) and reciprocal sCr may be unsuitable markers of graft function.

METHODS

In 17 kidney transplant patients with CAN, azathioprine (Aza) was replaced by MMF. The remaining therapy was not changed; specifically, the cyclosporine (CsA) dose was not decreased. The mean values and regression coefficients of reciprocal sCr, CCr, urinary creatinine excretion (uCr x V), proteinuria, BW, blood pressure (BP), serum cholesterol (sChol), and serum triglycerides (sTG) versus time were analyzed 12 months before and after institution of MMF by a paired-comparison t test.

RESULTS

The mean regression coefficient of reciprocal sCr differed significantly before and after conversion to MMF (mean -0.01 +/- 0.01 vs +0.012 +/- 0.029 mg/dL per month), suggesting improved graft function. However, the mean values of BW (74 +/- 15 vs 71 +/- 15 kg, P <.001) and uCr x V (1152 +/- 321 vs 1065 +/- 266 mg per 24 hours, P=.0897) decreased, making the increase in CCr less significant (mean -1.16 +/- 2.69 vs 0.40 +/- 1.79 mL/min per month, P <.05). BP, sChol, sTG, and proteinuria before and after conversion did not differ significantly. Among patients with long-term stable graft function at 36.5 +/- 16.9 months after conversion to MMF there was an almost significant improvement in renal protein excretion.

CONCLUSIONS

MMF improved graft function, although this effect was overestimated using reciprocal sCr. Other risk factors, such as BP, sChol, and sTG, showed no significant differences, suggesting that MMF accounted for the improvement in CAN. The course of proteinuria under MMF seems to be of prognostic significance.

Rapid Discontinuation of Prednisone in Higher-Risk Kidney Transplant Recipients

Prednisone-minimization protocols have been successful in low-risk recipients. We report on the use of a protocol incorporating rapid discontinuation of prednisone in a cohort of kidney transplant recipients (n = 79) at increased immunologic risk. Our data suggests that such recipients should not be excluded from prednisone-minimization protocols.

Sequential cytomegalovirus antigenemia monitoring in kidney transplant patients treated with antilymphocyte antibodies

BACKGROUND

Antilymphocyte antibodies (ALA) use is related to disseminated cytomegalovirus (CMV) disease after kidney transplantation. Strict surveillance of CMV infection, preemptive antiviral treatment or concomitant ganciclovir and ALA use are proposed as an attempt to prevent related clinical complications. Our objective was to describe the pattern of CMV infection, based on sequential antigenemia detection, after ALA treatment.

PATIENTS AND METHODS

Thirty renal transplant patients were prospectively screened for CMV infection after ALA treatment. CMV antigenemia (pp65 antigen detection) was monitored twice a week in the first month and weekly until 60 days after the beginning of ALA therapy. Any positive value of antigenemia was considered CMV infection.

RESULTS

Twenty-eight (93.3%) patients were CMV positive (IgG) before transplantation. The mean duration of ALA treatment was 12.1+/-2.4 days. Positive antigenemia was detected in 24 (80%) patients, a mean of 52.5+/-15 days after transplant and 44.7+/-14 days after the beginning of ALA treatment. The median antigenemia count was 7 positive cells/300,000 neutrophils (range: 1-227). Antigenemia preceded clinical symptoms by 5.8 days (0-28 days). Eighteen (75%) of 24 positive patients received ganciclovir treatment: 8 patients (26.7%) for viral syndrome, 2 patients (33.3%) for invasive disease, and 8 patients (26.7%) as part of preemptive therapy, asymptomatic with high antigenemia values. Six pp65-positive patients with low counts were followed up until a negative result and remained asymptomatic without any specific treatment.

CONCLUSION

CMV infection was frequent after ALA treatment in this group and generally occurred late after completion of treatment. Antigenemia was a reliable tool to guide preemptive treatment in these patients, and such strategy is an alternative option compared to the prophylactic use of ganciclovir with ALA treatment.

Delayed graft function may not adversely affect short-term renal allograft outcome

INTRODUCTION

Delayed graft function (DGF) is commonly believed to adversely impact both short- and long-term renal allograft function. Because immunosuppressive therapy is commonly altered after DGF is identified, retrospective analyses are difficult to interpret. We therefore prospectively sought to examine the natural history of DGF in a controlled patient population under identical immunosuppressive protocols.

METHODS

Adult patients undergoing cadaveric renal transplantation were treated with sequential triple drug immunotherapy. High-dose steroids were administered in the operating room and rapidly tapered to 20 mg prednisone by post-operative day (POD) 6. Cyclosporine (CsA) microemulsion was begun on POD 1, and dosed asymmetrically at 12-h intervals to reach a daytime Cav of 650 ng/mL (utilizing 2-h and 6-h levels), while PM doses were adjusted to an AM trough of 300 ng/mL. Mycophenolate (1000 mg q12 h) was added on POD 3 in most patients and discontinued after 3 months. No induction agents were used. All patients were followed for at least 6 months.

RESULTS

Sixty consecutive patients received 64 allografts (four double grafts). In all, 17 patients required dialysis and were considered to have DGF. Eight of these patients received marginal organs turned down by at least one other centre. Cold ischaemia time was significantly longer in patients with DGF (24 h vs. 19 h, P < 0.01) All patients were treated as planned and there were no major protocol violations. One patient had primary non-function and was excluded from analysis. CsA trough and Cav values were similar between groups. Mean serum creatinine levels (mg/mL) fell more slowly in patients with DGF but there was no significant difference by 3 months (1.7 vs. 1.5) and the creatinine clearance was not significantly different between the groups after 1 year (71 cm3/min in DGF vs. 61 cm3/min, P = 0.13). Our data demonstrate that alterations in routine immunosuppressive strategies may not be necessary to achieve equivalent outcomes in patients with DGF.

Risk factors for cytomegalovirus retinitis following bone marrow transplantation from unrelated donors in patients with severe aplastic anemia or myelodysplasia

Two cases of cytomegalovirus (CMV) retinitis following bone marrow transplantation (BMT) from unrelated donors are reported. 1 patient had been treated for severe aplastic anemia (SAA) and the other for hypoplastic myelodysplastic syndrome (MDS). Because first line therapy with antithymocyte globulin (ATG) and cyclosporin A (CsA) had failed, BMT was performed following a conditioning regimen of ATG, cyclophosphamide, and total lymphoid irradiation. Treatment for CMV retinitis was successfully carried out with gancyclovir (systemic and intraocular injection), foscarnet, and photocoagulation (Case 1) and gancyclovir and foscarnet (Case 2). Both patients also developed Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD). We compared these 2 cases with 14 SAA patients who did not develop CMV retinitis after BMT using marrow from either HLA-identical siblings (n = 9) or from unrelated donors (n = 5). Unlike the retinitis patients, the latter 5 patients received ATG only once. The retinitis patients had significantly lower CD4+ T-cell levels in their peripheral blood than the 14 patients who did not develop CMV retinitis. We believe that repeated treatment with ATG and transplantation from unrelated donors may lead to immune dysfunction that could increase the likelihood of CMV retinitis, as well as LPD. For such BMT patients, regular ophthalmic examinations and careful testing for CMV antigenemia are recommended.

A calcineurin antagonist-free induction strategy for immunosuppression in cadaveric kidney transplant recipients at risk for delayed graft function

BACKGROUND

Avoidance of calcineurin antagonists for a prolonged period de novo after cadaver donor renal transplantation may facilitate recovery from delayed graft function. The present study examined the benefit of prolonging the calcineurin antagonist-free interval by administering sirolimus (SRL) in combination with chimeric (c-) anti-interleukin-2 receptor (IL-2R) monoclonal antibodies (mAb).

METHODS

Three contemporaneous but nonrandomized cohorts were compared for acute rejection episodes, patient and graft survival rates, renal function, and adverse reaction profiles for 12 months. Patients with delayed graft function were treated with either SRL/c-IL-2R mAb/prednisone (Pred) with inception of cyclosporine (CsA) once the serum creatinine value was < or =2.5 mg/dl (n=43; group 1) or anti-lymphocyte preparations/Pred/delayed CsA for 7 to 14 days (n=18; group 3). A third cohort displayed immediate function and was treated de novo with CsA/c-IL-2R mAb/Pred (n=21; group 2).

RESULTS

The incidence of acute rejection episodes was significantly lower among group 1 (16%) compared with groups 2 (52%, P=0.004) or 3 (39%, P=0.05). Among the seven rejection episodes in group 1, six of seven occurred among African-American or retransplant recipients, and a separate cluster of six of seven occurred among patients who displayed SRL trough concentrations < or =9 ng/ml. Furthermore, additional antilymphocyte antibody treatment was required to reverse either steroid-resistant or Banff grades II or III acute rejection episodes among 14%, 55% (P=0.08), and 71% (P=0.03) of patients in each group, respectively. Patient and graft survival rates, as well as mean serum creatinine values, were similar at 12 months among the three groups. However, group 1 patients displayed higher serum cholesterol and triglyceride values, as well as lower hemoglobin, platelet, and leukocyte values compared with the other two groups.

CONCLUSION

This pilot study suggests that a SRL/c-IL-2R mAb/Pred induction regimen provides excellent acute rejection prophylaxis.

Mycophenolate mofetil, with cyclosporine and prednisone, reduces early rejection while allowing the use of less antilymphocytic agent induction and cyclosporine in renal recipients with delayed graft function

Antilymphocytic agent induction (ALAI), with antithymocyte globulin or monoclonal antibody, is generally used in renal transplantation (TX) to spare renal allografts with poor initial function from the toxic effects of cyclosporine (CsA) and/or to augment immunosuppression (IS) in the patient at a high risk for early rejection. ALAI, unfortunately, increases the cost of TX and the risk to the patient, having been associated with many adverse side effects. An IS protocol, which results in a low incidence of early rejection while using less CsA and ALAI, is a worthwhile goal. We compare our experience with mycophenolate mofetil (MMF), CsA, and prednisone (MMFCP; n = 62) to our azathioprine (AZA), CsA, and prednisone (AZACP; n = 50) triple-drug IS, with and without ALAI. The patient characteristics for age, race, first TX, cadaveric donor, pediatric recipient, and dialysis in the first post-op week (DGF) were not different for the MMFCP versus AZACP groups. There were more females in the MMFCP group (51.6% versus 30.0%, p = 0.022). We report that rejection-free survival at 6 months (RF6) was better in the MMFCP versus AZACP group (83.9% versus 60.0%, p = 0.005). Less ALAI and CsA were used in the MMFCP patients. At 1 year, actuarial graft survival was 91.9% in the MMFCP group and 81.9% in the AZACP group (p = 0.116). Actuarial 1-year patient survivals were not different in the two patient groups. In the sub-population of patients with DGF, the RF6 in the MMFCP (n = 13) group was 92.3% versus 57.1% in the AZACP (n = 14) group (p = 0.041). The reduction in early rejection episodes in the patients on MMFCP with DGF was accomplished while using half as much ALAI and lower CsA doses and levels. The African-American recipient sub-population on MMFCP also demonstrated an improvement in RF6 while using less ALAI and CsA (78.6% versus 48.0%, p = 0.022). We conclude that the use of MMF-based triple-drug IS results in fewer rejection episodes while allowing for lower CsA levels and less ALAI, even in patients with delayed graft function.