Steroid-free immunosuppression since 1999: 129 pediatric renal transplants with sustained graft and patient benefits

Growth of kidney-transplanted pediatric patients treated with sirolimus

Experimental findings indicate that sirolimus (SRL) inhibits longitudinal growth by mechanisms potentially related to its inhibitory effects on both cell proliferation and expression of vascular endothelial growth factor (VEGF). The aim of this study was to investigate the growth pattern of kidney-transplanted children treated with SRL in a multicenter observational clinical study. Height, change in height SD (Δ height) and growth velocity of pediatric patients with renal transplant were calculated at 0, 6, 12, and 24 months after starting SRL. Controls of kidney-transplanted children not treated with SRL were matched by age, gender, renal function, and dose of corticosteroids. Sixty-eight children (34 SRL, 34 controls) were enrolled in the study. Nephrotoxicity was the most frequent indication to start therapy with SRL. SRL exerted an adverse effect on growth as demonstrated by significantly lower (p < 0.05) growth velocity (cm/year) and smaller change in height SD in the SRL group after 6 (4.08 vs. 6.56 and -0.05 vs. 0.14), 12 (4.44 vs. 6.11 and -0.03 vs. 0.28) and 24 (4.53 vs. 6.03 and -0.04 vs. 0.53) months of treatment. This study suggests that SRL therapy may interfere with growth of kidney-transplanted children. This undesirable effect needs to be taken into account when considering a switch to SRL and confirmed in further prospective trials including larger number of patients.

Finding the right time for weaning off immunosuppression in solid organ transplant recipients

Solid organ transplantation (SOT) requires lifelong immunosuppression (IS) to prevent rejection and graft loss. The currently adopted immunosuppressive protocols are numerous and are based on the administration of at least two molecules with diverse mechanisms of action. Owing to the fact that the majority of immunosuppressants act non-selectively, the immune system is normally oversuppressed, and as a result is less able to both defend the host against infection and to control the spread of malignant cells. Consequently, long-term IS is burdened by chronic toxicity, which may be highly invalidating and may significantly influence patient's quality of life, compliance to treatment, overall success rate, and patient and graft survival. In an ideal scenario, SOT recipients should initially receive just enough IS to favor the onset of clinical operational tolerance (COT), a condition where the immune system of the host does not attack the graft in the absence of any immunosuppressant. COT has been documented after liver transplantation (LT) and renal transplantation (RT). First, COT was accidentally detected in patients who were nonadherent to treatment and who spontaneously decided to stop all IS without any medical guidance or surveillance. Later, it was described in recipients who required IS withdrawal following the occurrence of malignant diseases. Based on strikingly convincing experimental data, several tolerogenic protocols have recently been applied in patients but overall the results have been disappointing. The current literature demonstrates that COT can be safely achieved in stable LT recipients, with completely different strategies. Importantly, the onset of an episode of acute rejection during the attempt of IS withdrawal would not worsen the clinical outcome. On the contrary, COT remains a major challenge after RT because the onset of acute rejection will substantiate in graft loss. Currently, a major field of investigation aims to define markers of COT, which will allow the selection of individuals who are more prone to develop COT. Preliminary results in both RT and LT have just been announced; however, these markers will require validation in prospective studies.

The role and future challenges for recombinant growth hormone therapy to promote growth in children after renal transplantation

Chronic kidney disease can severely impair linear growth in children. For many children, growth improves after renal transplantation, but for some, growth velocity remains low and for others, catch-up growth is insufficient to compensate for the deficit imparted by renal disease in the preceding years. Inadequate final adult height after renal transplant is multifactorial and can adversely affect the quality of life (QOL), psychosocial development and long term prospects for these children as they grow into adulthood. Growth failure after renal transplant requires thorough evaluation and its management in renal transplant recipients can involve improved nutritional intake, correction of metabolic acidosis, treatment of secondary hyperparathyroidism, steroid-sparing immunosuppression and/or use of recombinant human growth hormone (rGH). Treatment with rGH after renal transplant has been evaluated by a limited number of clinical trials suggesting efficacy and safety for this treatment strategy. Several important clinical questions regarding rGH use in children post-renal transplant remain unanswered.

Pediatric kidney recipients with small capacity, defunctionalized urinary bladders receiving adult-sized kidney without prior bladder augmentation

BACKGROUND

Children with small capacity, defunctionalized urinary bladders present unique operative challenges. Thus, traditional practice has included pretransplant bladder augmentation, but this has several adverse consequences.

METHODS

A single-institutional, retrospective review from January 1, 2004 to December 31, 2008 was conducted. Twelve pediatric patients, whom had not undergone pretransplant bladder augmentation, did not have neurogenic bladders or require preoperative catheterization, and a small capacity defunctionalized bladders were included. All were managed by the same surgeon with a previously described ureteral implantation, and a 7F ureteral stent attached to a large diameter suprapubic catheter was removed in a joint manner without cystoscopy at 2 weeks. Data were collected on patient and graft survival, rejection episodes, urinary tract infection (UTI) requiring antibiotics, grade of vesicoureteral reflux, and posttransplant bladder capacity.

RESULTS

One-year patient and graft survival rates were 100%. One patient experienced a clinical rejection episode, which was successfully treated. Five patients (41.7%) had a UTI requiring abx treatment within the first postoperative year, but at 1 year, all patients had sterile urinary tracts. After removal of suprapubic catheters and ureteral stents, all patients were able to void spontaneously. Seven patients had no posttransplant ureteral reflux, three had grade 1 reflux, and two had grade 3 reflux (both successfully treated). The average age estimated pretransplant bladder and 1 year posttransplant bladder capacity was 14.5% and 84% of expected, respectively.

CONCLUSIONS

In pediatric end-stage renal disease patients with a small capacity defunctionalized bladder, it is reasonable to proceed with kidney transplantation without pretransplant bladder augmentation, thus avoiding an unnecessary surgery.

Efficacy and safety of thymoglobulin induction as an alternative approach for steroid-free maintenance immunosuppression in pediatric renal transplantation

BACKGROUND

Given the recent withdrawal of daclizumab (DAC), the safety and efficacy of thymoglobulin (TMG) was tested as an alternative induction agent for steroid-free (SF) immunosuppression in pediatric kidney transplant recipients.

METHODS

Thirteen pediatric renal transplant recipients meeting defined high-risk criteria at transplantation were offered TMG induction and SF immunosuppression with maintenance mycophenolate mofetil and tacrolimus between October 2008 and January 2010. Patients were closely monitored at baseline, 3, 6, 9, and 12 months posttransplant for protocol biopsy and clinical outcomes. Outcomes were compared with 13 consecutively transplanted low-risk patients receiving an established DAC-based SF protocol (Sarwal et al., WA, American Transplant Congress 2003).

RESULTS

There was a significant trend for overall decrease in the absolute lymphocyte counts in TMG group (F=5.86, mixed model group effect P=0.02), predominately at 3 months compared with DAC group (0.7±0.6 vs. 2.1±1.0, P=0.0004); however, lymphocyte count was recovered and was back to reference range by 6 months in TMG. There was trend toward more subclinical cytomegalovirus (15% vs. 0%) and BK viremia (17% vs. 0%) in the TMG group, with no differences in the incidence of subclinical Epstein Barr virus viremia (23% vs. 31%) or clinical viral disease. Mean graft function was excellent, and with a minimum follow-up of 6 months, there were no episodes of acute rejection.

CONCLUSION

TMG seems to be a safe alternative induction strategy in patients for SF immunosuppression in pediatric renal transplantation. Extended follow-up and greater enrollment are necessary to fully explore the impact of TMG dosing on viral replication posttransplantation.

Evaluation of the novel protein kinase C inhibitor sotrastaurin as immunosuppressive therapy after renal transplantation

IMPORTANCE OF THE FIELD

The prevalence of acute renal allograft rejection has decreased substantially in past decades due to new and more specific immunosuppressive compounds but improvements in long-term graft function have not been achieved. There is a large need for new immunosuppressive agents that lack toxicity of current agents such as calcineurin inhibitors but show high synergistic efficiency in preventing rejection processes.

AREAS COVERED IN THIS REVIEW

This review summarizes data concerning the pharmacokinetics, pharmacodynamics and clinical efficacy of the new PKC inhibitor sotrastaurin with a focus on renal transplantation. The article contains information that has been presented at international transplant meetings and congresses and that has been published between 2006 and 2010. Additionally, current ongoing trials are described in detail.

WHAT THE READER WILL GAIN

Immunosuppressive regimens after kidney transplantation consist of a combination of several agents in order to minimize drug toxicity. Therefore, the reader is presented with the most up-to-date/current developments in sotrastaurin applications in Phase I and II trials with emphasis on data maintained from studies that combined sotrastaurin with established agents such as mycophenolic acid and tacrolimus.

TAKE HOME MESSAGE

Several trials are ongoing and planned to determine the optimal immunosuppressive regimen to benefit from sotrastaurin's distinct mechanism of action.

Steroid minimization in pediatric renal transplantation: Early withdrawal or avoidance?

  Clinically important adverse events associated with the use of corticosteroids post-transplantation include hypertension, dyslipidemia, impaired glucose metabolism (including diabetes mellitus), growth retardation, bone fractures, and cosmetic problems. Over recent years, a number of studies have investigated the effect of minimizing exposure to corticosteroids in post-transplant immunosuppression protocols in both adults and children. In pediatric patients, several different approaches have been evaluated, including late steroid withdrawal, early steroid withdrawal, and complete steroid avoidance with or without poly- or monoclonal antibody induction and a variety of maintenance immunosuppressants. This manuscript reviews the key studies and documents the specific clinical benefits associated with steroid minimization. The development of PTLD and bone marrow suppression has been a major safety concern in some of these studies. These studies and other adverse effects are discussed.

Longitudinal relations between obesity and hypertension following pediatric renal transplantation

Obesity and hypertension frequently complicate renal transplantation (RTxp). The objective was to assess relations among obesity, hypertension, and glucocorticoids in pediatric RTxp recipients. A retrospective cohort study was carried out in 141 RTxp recipients, 2-21 years of age, with >or=12 months of follow-up. Body mass index Z-score (BMI-Z), systolic and diastolic blood pressure Z-scores (SBP-Z and DBP-Z), and medications at 1, 3, 6, and 12 months and annually thereafter were recorded. Quasi-least squares regression analysis was used. The prevalence of obesity (BMI>or=95th percentile) increased from 13% at baseline to >30% from 3 months onward. Greater glucocorticoid exposure (mg/kg/day) was associated with greater increases in BMI-Z (p<0.001). This association was greater in males, younger recipients, and those with lower baseline BMI-Z (all interactions p<0.02). The prevalence of systolic hypertension (SBP>or=95th percentile) was 73% at 1 month and >or=40% at all follow-up visits. Greater glucocorticoid exposure (p<0.001) and increases in BMI-Z (p=0.005) were independent determinants of SBP-Z over time. Cyclosporine (versus tacrolimus) was independently associated with greater SBP-Z and DBP-Z (p=0.001). Sustained obesity and hypertension frequently complicated pediatric RTxp. Obesity was an independent determinant of systolic hypertension. Strategies are needed to prevent obesity and its impact on hypertension, cardiovascular disease, and allograft survival.

De novo therapy with everolimus, low-dose ciclosporine A, basiliximab and steroid elimination in pediatric kidney transplantation

The number of acute rejections and infections after pediatric kidney transplantation (KTX) could not be reduced in the last years. To reduce these events, we investigated a new immunosuppressive protocol in a prospective trial. After KTX, 20 children (median age 12 years, range 1-17) were initially treated with Basiliximab, ciclosporine A (CsA) (trough-level = C0 200-250 ng/mL) and prednisolone. After 2 weeks, CsA dose was reduced to 50% (C0 75-100 ng/mL, after 6 months: 50-75 ng/mL) and everolimus (1.6 mg/m²) /day) was started (C0 3-6 ng/mL). Six months after KTX prednisolone was set to alternate dose and stopped 3 months later. All 20 protocol biopsies 6 months after KTX showed no acute rejection or borderline findings. Indication biopsies resulted in no acute rejections and two borderline findings. Mean glomerular filtration rate (GFR) 1 year after KTX was 71 ± 25 mL/min/1.73 m². Without cytomegalovirus (CMV)-prophylaxis, only two primary CMV infections were seen despite a donor/recipient-CMV-constellation pos./neg. in 10/20 children. In pediatric KTX, de novo immunosuppression with low-dose CsA, everolimus and steroid withdrawal after 9 months led to promising results according to numbers of acute rejections and infections. Further follow up is needed. Future larger trials will have to confirm our findings.

Effects of steroid avoidance and novel protocols on growth in paediatric renal transplant patients

The vast majority of kidney transplant recipients undergo triple maintenance immunosuppression that includes the use of steroids. Irrespective of their long history in organ transplantation and proven efficacy in preventing acute graft rejection, steroids exhibit an unfavourable toxicity profile, including growth retardation in children. Given these negative effects, therapeutic approaches that will substantially decrease patients' exposure to steroids have been considered. The planned approaches included alternate day administration, rapid or late steroid withdrawal at the pre-scheduled time after transplantation and complete steroid avoidance. All three of these strategies have been tested in single- or multicentre studies and shown to have distinct clinical advantages in terms of decreasing the incidence and severity of specific adverse events. However, the safety of these protocols could not be universally proven. The Stanford study showed that a complete steroid avoidance under the "cover" of tacrolimus, mycophenolate mofetil and extended daclizumab induction is a very effective regimen for obtaining an improvement in post-transplantation growth. The recently reported international randomized TWIST trial demonstrated growth improvement as early as 6 months post-transplantation. These protocols may potentially enable paediatric renal graft recipients to safely avoid steroid exposure.

Etiology and treatment of growth retardation in children with chronic kidney disease and end-stage renal disease: a historical perspective

Dramatic changes have occurred in our understanding of the etiology of the growth retardation associated with chronic kidney disease (CKD) and end-stage renal disease (ESRD) during the past 50 years. Significant interest has been focused on preventing and/or correcting the growth retardation because of the emergence of the dual therapeutic modalities of dialysis and renal transplantation to prolong the lives of infants, children, and adolescents afflicted with CKD and ESRD. These efforts have resulted in a significant improvement in the height Z-score over the past two decades of children with CKD and ESRD. This has had a salutary impact on the final adult height of such children which should hopefully lead to an enhanced quality of life in the future. This report addresses the progress that has been made in the management of growth retardation in the pediatric population with CKD and ESRD.

Nonimmune complications after transplantation

As posttransplant longevity has increased, nonimmune complications related to the transplant and posttransplant course have emerged as important factors in defining long-term outcomes. The incidence of, and risk factors for these complications may vary by transplanted organ based on immunosuppressive protocols and preexisting risk factors. This article discusses the relevant nonimmune complications associated with posttransplant care, with a focus on risk factors and management strategies.

Pediatric renal transplantation: an overview and update

PURPOSE OF REVIEW

Transplantation is the preferred method of treatment for end-stage renal disease in children. The rate of pediatric kidney transplantation has been steadily rising over the past decade. The use of increasingly potent immunosuppressive drugs has lessened the risk for acute rejection substantially and improved short-term outcomes; however, the long-term outcomes have remained inadequate.

RECENT FINDINGS

The follow-up of pediatric cohorts and the encouraging results from data registries prompt us to revisit our practices in transplantation so as to devise additional strategies to improve long-term outcomes.

SUMMARY

This review presents a comprehensive discussion of the major issues in pediatric renal transplantation, the newer immunosuppression approaches to limit toxicities of therapies in children and some critical issues that remain to be addressed, specific to the care of the transplanted child. The ultimate goal of designing optimum conditions for equating graft survival to patient survival still remains a major goal for pediatric organ transplantation.

The baseline ratio of neutrophils to lymphocytes is associated with patient prognosis in advanced gastric cancer

OBJECTIVE

In cancer patients, the balance between neutrophil (N) and lymphocyte (L) cell counts fluctuates with advancing disease. The objective of our study was to determine the prognostic implications of the N/L ratio in the peripheral blood of gastric cancer patients.

METHODS

Study participants were identified from a prospective cohort of patients with advanced gastric cancer in Japan (n = 1,220).

RESULTS

The median baseline N/L was 2.58 (range, 0.63-12.7). Univariate analysis revealed that patients with an N/L > pr =2.5 (n = 644) had a significantly poorer prognosis than those with an N/L <2.5 (n = 576; log rank test, p = 0.019 x 10(-12)). The median survival times for these two groups were 239 (95% confidence interval, CI, 217-251 days) and 363 days (95% CI, 334-406 days), respectively, while the 1-year survival rates were 30 (95% CI, 26-34%) and 50% (95% CI, 45-54%), respectively. A multivariate Cox model established a significant relationship between the N/L ratio and survival (adjusted hazard ratio = 1.52; 95% CI, 1.32-1.75; p = 0.077 x 10(-8)).

CONCLUSIONS

These results suggest that the N/L ratio is an independent prognostic factor in advanced gastric cancer. Measurement of this ratio may serve as a clinically accessible and useful biomarker for patient survival.