Safety and infectious outcomes in pediatric kidney transplant recipients after COVID-19 vaccination: A pediatric nephrology research consortium study.

BACKGROUND: Adult kidney transplant recipients (KTRs) fully vaccinated against COVID-19 have substantial morbidity and mortality related to SARS-CoV-2 infection compared with the general population. However, little is known regarding the safety and efficacy of the COVID-19 vaccination series in pediatric KTRs. METHODS: A multicenter, retrospective observational study was performed across nine pediatric transplantation centers. Eligible KTRs fully vaccinated against COVID-19 were enrolled and data were collected pertaining to SARS-CoV-2 infection incidence and severity, graft outcomes and post-vaccination safety profile, as well as overall patient survival. RESULTS: A total of 247 patients were included in this investigation with a median age at transplantation of 11 years (IQR 5-15). SARS-CoV-2 infection was observed in 30/110 (27.27%) of fully vaccinated patients, tested post-transplant, within the defined follow-up period. Of these patients, 6/30 (18.18%) required hospitalization and 3/30 (12.12%) required reduction in immunosuppression, with no reported deaths. De novo donor-specific antibodies (DSAs) were found in 8/86 (9.30%) of DSA-tested patients with two experiencing rejection and subsequent graft loss. The overall incidence of rejection and graft loss among the total cohort was 11/247 (4.45%) and 6/247 (3.64%), respectively. A 100% patient survival was observed. CONCLUSIONS: Observationally, infectious outcomes of SARS-CoV-2 in fully vaccinated pediatric KTRs are excellent, with a low incidence of infection requiring hospitalization and no associated deaths. Though de novo DSAs were observed, there was minimal graft rejection and graft loss reported in the total cohort.

Severe labile hypertension in a patient with catecholamine-secreting neuroblastoma: a case report.

Neuroblastoma is a common pediatric tumor arising from the post-ganglionic sympathetic nervous system and is associated with hypertension in 25% of cases. We describe an unusual case of labile, multi-drug resistant hypertension associated with chemotherapy administration for neuroblastoma and provide potential management strategies in this scenario. We report the case of a 4-year-old female with a history of headaches who presented with hypertensive emergency and evidence of end-organ damage, including posterior reversible encephalopathy syndrome, acute cerebral infarct, concentric left ventricular hypertrophy, and growth failure secondary to a large, abdominal catecholamine-secreting neuroblastoma, which compressed the kidney vasculature and inferior vena cava. She was classified as intermediate risk according to Children's Oncology Group criteria and underwent chemotherapy, complicated by labile hypertension, followed by surgical resection. Vigilance in monitoring and treatment of hypertension is recommended during chemotherapy for neuroblastoma due to the potential catecholamine release in the setting of tumor lysis.

Body mass index in pediatric kidney transplant selection criteria.

BACKGROUND: Obesity is associated with increased complications, rejection, and graft loss after kidney transplantation in adult and pediatric recipients. Elevated body mass index (BMI) is a common contraindication to transplant at adult kidney transplant programs; however, there is no data on such limitations for pediatric patients. METHODS: Between October and December 2022, we conducted a survey of Pediatric Nephrology Research Consortium centers assessing the use of BMI in pediatric kidney transplant evaluation. Centers reporting utilization of BMI cutoffs were invited to submit patient-level data on children declined for active transplant listing due to BMI. RESULTS: Thirty-nine centers responded to the survey (42% response rate); 51% include BMI in their written listing criteria, with a median BMI "cutoff" of 39 kg/m2 (range 30-50 kg/m2). Between January 1, 2016, and December 31, 2021, 30 children at 15 transplant centers were declined for listing status due to BMI. Patient-level data was provided for 19 children (63%) who were denied active listing status; median BMI was 42 kg/m2 (range 35.8-49.4 kg/m2) and 84% were on dialysis. One year after evaluation, seven patients (37%) had proceeded to active wait list status. Eight (42%) remained in inactive status and four (21%) were unlisted; ten of these 12 patients (83%) were on dialysis. CONCLUSIONS: The use of BMI in pediatric kidney transplant evaluation and listing varies among centers, but BMI limits access to transplant for some children. More information is needed on the outcomes of obese pediatric kidney candidates who are and are not transplanted, to guide development of national and international consensus.

Responding to the workforce crisis: consensus recommendations from the Second Workforce Summit of the American Society of Pediatric Nephrology.

IMPORTANCE: Pediatric patients with complex medical problems benefit from pediatric sub-specialty care; however, a significant proportion of children live greater than 80 mi. away from pediatric sub-specialty care. OBJECTIVE: To identify current knowledge gaps and outline concrete next steps to make progress on issues that have persistently challenged the pediatric nephrology workforce. EVIDENCE REVIEW: Workforce Summit 2.0 employed the round table format and methodology for consensus building using adapted Delphi principles. Content domains were identified via input from the ASPN Workforce Committee, the ASPN's 2023 Strategic Plan survey, the ASPN's Pediatric Nephrology Division Directors survey, and ongoing feedback from ASPN members. Working groups met prior to the Summit to conduct an organized literature review and establish key questions to be addressed. The Summit was held in-person in November 2023. During the Summit, work groups presented their preliminary findings, and the at-large group developed the key action statements and future directions. FINDINGS: A holistic appraisal of the effort required to cover inpatient and outpatient sub-specialty care will help define faculty effort and time distribution. Most pediatric nephrologists practice in academic settings, so work beyond clinical care including education, research, advocacy, and administrative/service tasks may form a substantial amount of a faculty member's time and effort. An academic relative value unit (RVU) may assist in creating a more inclusive assessment of their contributions to their academic practice. Pediatric sub-specialties, such as nephrology, contribute to the clinical mission and care of their institutions beyond their direct billable RVUs. Advocacy throughout the field of pediatrics is necessary in order for reimbursement of pediatric sub-specialist care to accurately reflect the time and effort required to address complex care needs. Flexible, individualized training pathways may improve recruitment into sub-specialty fields such as nephrology. CONCLUSIONS AND RELEVANCE: The workforce crisis facing the pediatric nephrology field is echoed throughout many pediatric sub-specialties. Efforts to improve recruitment, retention, and reimbursement are necessary to improve the care delivered to pediatric patients.

The unfinished journey toward transplant equity: an analysis of racial/ethnic disparities for children after the implementation of the Kidney Allocation System in 2014.

BACKGROUND: Disparities in pediatric kidney transplantation (KT) result in reduced access and worse outcomes for minority children. We assessed the impact of recent systems changes on these disparities. METHODS: This is a retrospective cohort study of pediatric patients utilizing data from the US Renal Data System (n = 7547) and Scientific Registry of Transplant Recipients (n = 6567 waitlisted and n = 6848 transplanted patients). We compared access to transplantation, time to deceased donor kidney transplant (DDKT), and allograft failure (ACGF) in the 5 years preceding implementation of the Kidney Allocation System (KAS) to the 5 years post-KAS implementation 2010-2014 vs. 2015-2019, respectively. RESULTS: Compared to the pre-KAS era, post-KAS candidates were more likely to be pre-emptively listed (26.8% vs. 38.1%, p < 0.001), pre-emptively transplanted (23.8% vs. 28.0%, p < 0.001), and less likely to have private insurance (35.6% vs. 32.3%, p = 0.01), but these were not uniform across racial groups. Compared to white children, Black and Hispanic children had a lower likelihood of transplant listing within 2 years of first dialysis service (aHR 0.590.670.76 and 0.730.820.92, respectively) in the post-KAS era. Time to DDKT was comparable across all racial groups in the post-KAS era. Compared to white children, Black DDKT recipients have more 5-year ACGF (aHR 1.001.432.06 p = 0.05) while there was no difference in 3- or 5-year ACGF among LDKT recipients. CONCLUSIONS: After KAS implementation, there is equity in time to DDKT. Pre-KAS increased hazard of ACGF among Black children has decreased in the post-KAS era; however, persistent disparities exist in time to transplant listing among Black and Hispanic children when compared to white children. A higher resolution version of the Graphical abstract is available as Supplementary information.

Acute kidney injury requiring kidney replacement therapy in childhood lupus nephritis: a cohort study of the Pediatric Nephrology Research Consortium and Childhood Arthritis and Rheumatology Research Alliance.

BACKGROUND: Acute kidney injury (AKI) is common in lupus nephritis (LN) and a risk factor for development of chronic kidney disease. In adults with LN, AKI severity correlates with the incidence of kidney failure and patient survival. Data on AKI outcomes in children with LN, particularly those requiring kidney replacement therapy (KRT), are limited. METHODS: A multicenter, retrospective cohort study was performed in children diagnosed between 2010 and 2019 with LN and AKI stage 3 treated with dialysis (AKI stage 3D). Descriptive statistics were used to characterize demographics, clinical data, and kidney biopsy findings; treatment data for LN were not included. Logistic regression was used to examine the association of these variables with kidney failure. RESULTS: Fifty-nine patients (mean age 14.3 years, 84.7% female) were identified. The most common KRT indications were fluid overload (86.4%) and elevated blood urea nitrogen/creatinine (74.6%). Mean follow-up duration was 3.9 ± 2.9 years. AKI recovery without progression to kidney failure occurred in 37.3% of patients. AKI recovery with later progression to kidney failure occurred in 25.4% of patients, and there was no kidney recovery from AKI in 35.6% of patients. Older age, severe (> 50%) tubular atrophy and interstitial fibrosis, and National Institutes of Health (NIH) chronicity index score > 4 on kidney biopsy were associated with kidney failure. CONCLUSIONS: Children with LN and AKI stage 3D have a high long-term risk of kidney failure. Severe tubular atrophy and interstitial fibrosis at the time of AKI, but not AKI duration, are predictive of kidney disease progression. A higher resolution version of the Graphical abstract is available as Supplementary information.

Primary pediatric deceased-donor kidney transplant recipients outcomes by immunosuppression induction received in the United States.

BACKGROUND: We studied the association of induction immunosuppression and pediatric deceased-donor kidney recipient and graft survival. METHODS: We utilized the SRTR to evaluate all primary pediatric deceased-donor kidney transplants from January 1st, 2000, through December 2018. We included only recipients who were maintained on tacrolimus and mycophenolate. Recipients were grouped by induction type: alemtuzumab n = 320, r-ATG n = 2091 and IL-2RA n = 2165. Recipient and allograft survival, and their predictors, were examined. Models were adjusted for age, sex, ethnicity, HLA-antigen mismatches, transplant year, steroid maintenance, pre-emptive transplantation and payor type, with the transplant center included as a random effect. RESULTS: Rejection rates at 6 months (alemtuzumab 8.6% vs r-ATG 7.8% vs IL2-RA 9.2%; P = .30) and 12 months (alemtuzumab 17.2% vs r-ATG 15.7% vs IL2-RA 16.5%; P = .70) were not significantly different between induction groups. In the multivariable models, compared to IL-2RA neither alemtuzumab nor r-ATG was associated with improved recipient [alemtuzumab (HR 1.06, P = .88); r-ATG (HR 1.03, P = .84)] or graft survival [alemtuzumab (HR 1.18, P = .32); r-ATG (HR 1.10, P = .21)]. CONCLUSION: In this large cohort of standard immunological risk primary pediatric deceased-donor kidney recipients on tacrolimus and mycophenolate maintenance, depletional induction regimens were not associated with better rejection rates, recipient, or graft survival compared to IL-2RA induction. Racial, payor type, and sex-related outcome disparities were significant in this group independent of the induction choice.

Primary pediatric live-donor-kidney transplant-recipients' outcomes by immunosuppression induction received in the United States.

OBJECTIVE: We examined the association between induction type and outcomes of live-donor pediatric kidney recipients on tacrolimus and mycophenolate maintenance. MATERIAL AND METHODS: We analyzed the SRTR standard analysis file to evaluate primary live-donor pediatric kidney recipients between 2000 and 2018. Recipients were grouped by induction type into three groups: alemtuzumab n = 289, anti-thymocyte n = 1197, and IL-2RA n = 1625. Kaplan-Meier curves were generated for recipient and death-censored graft survival. Predictors of recipient and allograft survival were examined using Cox proportional hazards models. Models were adjusted for age, sex, ethnicity, renal failure etiology, HLA-mismatches, transplant year, steroid maintenance, preemptive transplantation, payor type, and donor factors such as age, sex, and donor-recipient relationship. The transplant center was included as a random effect to account for inter-center variability. RESULTS: Rejection rates at 6 months (Alemtuzumab 9.5% vs. r-ATG 5.7% vs. IL2-RA 5.3%; P: .023) and 12 months (Alemtuzumab 14.5% vs. r-ATG 10.8% vs. IL2-RA 9%; P: .028) were significantly higher in the alemtuzumab group. PTLD rate (Alemtuzumab 0.8% vs. r-ATG 2.2% vs. IL2-RA 1%; P: .028) was significantly higher in the anti-thymocyte group. In the multivariable models, induction type did not influence patient or death-censored graft survival within ten years post-transplant. CONCLUSION: In this large cohort of standard immunological risk primary pediatric live-donor kidney recipients, as compared to IL-2RA, neither alemtuzumab nor anti-thymocyte globulin was associated with improved long-term graft or recipient survival. In the first year post-transplant, recipients of alemtuzumab induction had a higher rejection rate, while PTLD was more frequently observed in the anti-thymocyte recipients.

Dapsone-induced methemoglobinemia in pediatrics post-renal transplant.

Dapsone has been utilized for the prevention of Pneumocystis jirovecii pneumonia in immunosuppressed patients including pediatric kidney transplant recipients, in whom trimethoprim-sulfamethoxazole (TMP-SMX) is contraindicated. Dapsone adverse effects include methemoglobinemia, but there are no reports of the burden and impact of methemoglobinemia in pediatric kidney recipients that are taking dapsone for PJP prophylaxis. We conducted a retrospective chart review of all pediatric kidney recipients who had received dapsone at any time posttransplant. The indication, duration, and adverse effects of dapsone therapy were assessed. In addition, methemoglobin levels were assessed, and summary statistics performed. Data demonstrated that more than half of the patients on dapsone were not screened for methemoglobinemia. Of those screened, there was a significantly higher acquired-methemoglobinemia (77%) than previously reported in the literature. We also demonstrate significantly more anemia in patients on dapsone. Methemoglobinemia did not affect patient or graft survival and resolved with cessation of dapsone. We conclude that pediatric kidney recipients often develop methemoglobinemia and / or anemia on dapsone. We recommend if pediatric transplant recipients are prescribed dapsone, routine testing for methemoglobinemia and anemia should be done.

Timing of native nephrectomy and kidney transplant outcomes in children.

BACKGROUND: No consensus exists on the optimal timing for native nephrectomy in pediatric kidney transplant recipients. Data comparing outcomes between recipients undergoing pretransplant nephrectomy (staged nephrectomy with subsequent transplant) and those undergoing nephrectomy simultaneously with the transplant are lacking. METHOD: We studied 32 pediatric kidney transplant recipients who underwent native nephrectomy at a single center from 01/01/2011 to 12/31/2016. We divided recipients into two groups based on the nephrectomy timing (simultaneous nephrectomy/transplant and staged nephrectomy). We used Wilcoxon rank-sum test, Fisher's exact test, and Kaplan-Meier methods to compare outcomes. RESULTS: Of 32 recipients, 20 underwent simultaneous and 12 underwent staged nephrectomy. Simultaneous recipients were younger (median (years): 2.0 vs 7.0; P = .049). Staged recipients were more likely to have proteinuria/hypoalbuminemia, whereas simultaneous recipients were more likely to have hydronephrosis/vesicoureteral reflux/urinary infections as nephrectomy indications (P = .06). Median prenephrectomy albumin for patients with nephrotic syndrome was significantly lower in staged recipients (median g/dL: 1.9 vs 3.8; P = .02). Total number of hospital days (including both procedures) was higher for staged recipients compared with simultaneous (one procedure) recipients (median (days): 17.0 vs 11.5; P = .05). We observed no difference in 5-year graft survival between the groups (95.0% vs 91.7%, P = .73). Patient survival was 100% in both groups over a median follow-up of 44.2 months. Surgical complications were similar between the groups. CONCLUSION: Staged and simultaneous native nephrectomy in pediatric kidney transplant recipients are associated with comparable outcomes.

Re-transplantation in pediatric patients with failure of primary transplant due to recurrent focal segmental glomerulosclerosis: A pediatric nephrology research consortium study.

INTRODUCTION: Recurrent focal and segmental glomerulosclerosis (FSGS) in kidney transplant recipients is associated with lower graft survival and increased morbidity. There are limited data to guide the decision to re-transplant patients with transplant failure due to FSGS recurrence. We aimed to evaluate outcomes in patients re-transplanted after having initial graft failure due to recurrent FSGS and to study physician attitudes and practice patterns. METHODS: Retrospective data from 10 centers were collected on 20 patients transplanted between January 1997 and September 2018. A survey was sent to nephrologist members of the Pediatric Nephrology Research Consortium. RESULTS: Mean patient age (years) was 9.8 ± 4.8 at first transplant and 15.9 ± 4.9 at re-transplantation. Pre-transplant plasmapheresis was used in 1 (5.3%) primary transplant vs. 7 (38.9%) re-transplants (p = .03). Nephrotic syndrome recurred in 14 patients (70%) after re-transplantation and was severe in 21.1% vs. 64.7% after first transplant (p = .04). Graft survival was significantly higher in the second transplant (p .009) with 70% having functioning grafts at a median of 25.2 months. Thirty-one physicians from 21 centers completed the survey, 94% indicated they would re-transplant such patients, 44.4% preferred a minimum waiting period before re-transplantation, 36.4% preferred living donors, and 22.2% indicated having protocols for re-transplantation at their centers. CONCLUSIONS: Consideration for re-transplantation is high among pediatric nephrologists. Pre-transplant plasmapheresis was more frequent in re-transplanted patients. Nephrotic syndrome recurrence was less severe, with better graft survival. More data and a larger population are necessary to further evaluate outcome determinants and best practices in this special population.

Practice patterns and influence of allograft nephrectomy in pediatric kidney re-transplantation: A pediatric nephrology research consortium study.

INTRODUCTION: There are no guidelines regarding management of failed pediatric renal transplants. MATERIALS & METHODS: We performed a first of its kind multicenter study assessing prevalence of transplant nephrectomy, patient characteristics, and outcomes in pediatric renal transplant recipients with graft failure from January 1, 2006, to December 31, 2016. RESULTS: Fourteen centers contributed data on 186 pediatric recipients with failed transplants. The 76 recipients that underwent transplant nephrectomy were not significantly different from the 110 without nephrectomy in donor or recipient demographics. Fifty-three percent of graft nephrectomies were within a year of transplant. Graft tenderness prompted transplant nephrectomy in 91% (P < .001). Patients that underwent nephrectomy were more likely to have a prior diagnosis of rejection within 3 months (43% vs 29%; P = .04). Nephrectomy of allografts did not affect time to re-listing, donor source at re-transplant but significantly decreased time to (P = .009) and incidence (P = .0002) of complete cessation of immunosuppression post-graft failure. Following transplant nephrectomy, recipients were significantly more likely to have rejection after re-transplant (18% vs 7%; P = .03) and multiple rejections in first year after re-transplant (7% vs 1%; P = .03). CONCLUSIONS: Practices pertaining to failed renal allografts are inconsistent-40% of failed pediatric renal allografts underwent nephrectomy. Graft tenderness frequently prompted transplant nephrectomy. There is no apparent benefit to graft nephrectomy related to sensitization; but timing / frequency of immunosuppression withdrawal is significantly different with slightly increased risk for rejection following re-transplant.

Re-hospitalization after pediatric kidney transplant: A single-center study.

BACKGROUND: Little data exist on re-hospitalization rates in pediatric kidney recipients (KTx) particularly with the evolution of transplant immunosuppression. METHODS: In a single-center, retrospective study of pediatric KTx between 2006 and 2016, we assessed re-hospitalization after KTx admission, stratified by whether the re-admit was early (<30 days post-KTx discharge) or late (>30 days), and compared two different immunosuppression eras (one with and one without steroids). RESULTS: Of 197 KTx, 156 (79%) patients were re-hospitalized in 1st year, 85 (56%) within 30 days of discharge (total 490 1st year re-hospitalizations). Younger age was associated with early and late re-hospitalizations. African American race was associated with early re-hospitalizations. Of the 123 and 74 discharged on steroid-avoidance (maintenance immunosuppression included MMF in 95%; FK in 50%; CSA in 50%) and steroid-inclusive (AZA in 66%; MMF in 34%; FK in 30%; CSA in 70%), re-hospitalization rates, timing post-transplant, length, and number were not significantly different (P .38; .1; .56; .11). Admission diagnoses analysis demonstrated that steroid-avoidance recipients had anemia/leucopenia/thrombocytopenia, significantly more often, as one of their admission diagnoses (16% vs 4%; P < .001) and had a rejection diagnosis significantly less often (6% vs 18%; P < .001). Infection diagnoses were not statistically different between groups. Re-hospitalization, early or late, did not predict worse graft/ patient survival but predicted further hospitalizations. CONCLUSIONS: Re-hospitalization is common after pediatric transplant discharge and predicts further hospitalization regardless of discharge on or off steroids.

Use of oral immunoglobulins to treat diarrhea in pediatric kidney transplant recipients-Single-center experience and review of the literature.

Effective treatment modalities for diarrhea in solid organ transplant recipients are lacking. We evaluated the effect of oral IgG on clinical course of diarrhea in pediatric kidney transplant recipients. We retrospectively studied all pediatric kidney transplant recipients who required hospitalization for diarrhea between January 1, 2015, and December 31, 2017. We divided the recipients into two groups based on whether they had received oral IgG to treat diarrhea. Sixteen pediatric kidney transplant recipients required hospitalization for diarrhea over 3 years. Median age at admission was 9.25 years (IQR:12.54). Fifty-six percent of recipients were male, and 81% were white. Four patients received oral IgG for prolonged diarrhea. Oral IgG recipients had longer diarrheal duration before admission (median (days) 14.5 vs1; P .02), a trend for greater weight loss at admission (median (kilogram) 1.4 vs 0.2; P .3), and a trend for higher acute kidney injury (>75% reduction in glomerular filtration rate: 100% vs 42%; P .36). Diarrhea resolved completely in 3 (75%) oral IgG recipients and 7 (58%) non-oral IgG patients by discharge (P .99). One oral IgG recipient showed partial improvement but also had biopsy evidence of mycophenolate-induced colitis. All patients tolerated oral IgG well. No patients required re-hospitalization within 30 days of discharge. Oral IgG may be used safely and effectively to treat prolonged diarrhea in pediatric kidney transplant recipients. A larger, randomized, prospective study is needed to further assess the efficacy of oral IgG in the treatment of diarrhea.

Outcomes of kidney transplants in pediatric patients with the vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, limb abnormalities association.

In this single-center retrospective study, we analyzed kidney transplant outcomes in nine pediatric patients with VACTERL [vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, limb abnormalities] association-making this the largest study of its kind. Of 743 pediatric kidney transplant recipients at our center (1980-2017), nine had documented diagnoses of VACTERL association. All nine had congenital anorectal malformations and renal anomalies, five had vertebral defects, and one had a bifid thumb and tracheoesophageal fistula. Renal anomalies included dysplasia (n = 6), aplasia (n = 3), and horseshoe kidney (n = 2). Congenital lower urinary tract anomalies included neurogenic bladder (n = 6), obstructive uropathy (n = 4), anovesicular fistula (n = 1), rectourethral fistula (n = 1), and posterior urethral valves (n = 1). Age at transplant ranged from 1.2 to 15 years (mean, 7.3; standard deviation [SD], 5.5); 6 (67%) were male, and 3 (33%) were female; 6 (67%) had a living related donor, and 3 (33%) had a deceased donor. The overall graft survival rate was 78% (range, 1.5 to 25.2 years; mean, 10.5; SD, 8.9). One month post-transplant, one recipient died with a functioning graft. At 3.7 years post-transplant, one graft failed because of recurrent pyelonephritis. Post-transplant urologic complications included pyelonephritis (n = 6), vesicoureteral reflux (n = 5), and graft hydronephrosis (n = 4). We conclude that pediatric patients with VACTERL association can be safely transplanted-careful patient selection with vigilance and intervention for pre- and post-transplant urologic complications is essential.

Effects of the influenza vaccine on pediatric kidney transplant outcomes.

The influenza vaccine is critical for preventing influenza-related complications in transplant patients. Previous studies demonstrated de novo donor-specific antibody formation and rejection following the influenza vaccination. This risk has not been adequately assessed in the pediatric population. We performed a single-center retrospective analysis of 187 unique pediatric kidney transplant recipients, transplanted from January 1, 2006, to December 31, 2015, assessing for an association of the influenza vaccination with various transplant outcomes. The influenza vaccine was received by 125 of 187 patients within the first year post-transplant. Using log-rank tests and Kaplan-Meier curves, vaccinated patients had a significantly lower risk of mortality (P = 0.048). There were no differences in death-censored graft survival (P = 0.253), graft survival (P = 0.098), or rejection (P = 0.195) between vaccinated and unvaccinated groups. To address the problem of multiple exposures for a yearly vaccine, Cox proportional hazards regression was utilized with post-transplant vaccination status considered as a time-dependent covariate; analyses were performed using both a 360- and 180-day vaccination period following any post-transplant influenza vaccination. In this model, being vaccinated did not result in a significant difference in mortality (HR 0.90 [0.16, 5.15], P = 0.91), death-censored graft survival (HR 0.70 [0.31, 1.58], P = 0.39), graft survival (HR 0.69 [0.32, 1.49], P = 0.34), or rejection (HR 0.67 [0.37, 1.19], P = 0.17). Eight patients developed de novo donor-specific antibodies following the first post-transplant influenza vaccination; three then developed biopsy-proven rejection. These results suggest influenza vaccination is safe in pediatric kidney transplant recipients, and larger prospective studies are required to conclusively confirm our findings.

Mixed epithelial and stromal tumor after pediatric kidney transplant.

MEST of the kidney are a benign group of tumors with very rare incidence of malignant transformation. First described in 1998, this tumor has never been reported in a transplanted organ before. We present a unique case of de novo MEST in a donor kidney 4 years after transplant into a pediatric patient. Although removal of the lesions is curative without risking malignant transformation, in this case, surgical removal was not attempted to prevent reduction in transplant longevity. In this unique report of MEST in a transplanted kidney, we describe the patient/transplant outcomes without MEST resection.

Pediatric kidney transplantation: a historical review.

Successful renal transplantation is the optimal treatment for chronic kidney failure, but this was not always so for children. Beginning with the first kidney transplants in the 1950s, children experienced poorer patient and graft survival rates than adult patients. But over the last 6 decades, an improved understanding of the immune system which has steered pediatric multi-center clinical/pharmacokinetic and mechanistic studies that have sculpted our immunosuppression with markedly better patient and graft survivals. In addition, uniquely pediatric issues related to growth, development, neurocognitive maturation, increased complications from primary viral infections, and comorbid congenital/inherited disorders, are now diagnosed and effectively managed in these children. Refined pretransplant preparation (vaccinations for preventable diseases, attention to cognitive delays, effective dialysis and nutrition) improved donor selection, and more potent immunosuppression have all contributed to enhanced outcomes. Similarly, improvements in pediatric surgical techniques, postoperative care and better antiviral prophylaxis have all shortened hospitalizations and reduced morbidity. Today pediatric kidney transplant outcomes are markedly improved and younger children today experience better long-term graft survival than adults! While difficult problems remain, we have made tremendous progress and anticipate even more advances in the future of pediatric kidney transplantation.