Outcomes of cardiac transplantation in highly sensitized pediatric patients

Despite aggressive immunosuppressive therapy, pediatric orthotopic heart transplant (OHT) candidates with elevated pre-transplant panel reactive antibody (PRA) carry an increased risk of rejection and early graft failure following transplantation. This study has aimed to more specifically evaluate the outcomes of transplant candidates stratified by PRA values. Records of pediatric patients listed for OHT between April 2004 and July 2008 were reviewed (n = 101). Survival analysis was performed comparing patients with PRA < 25 to those with PRA > 25, as well as patients with PRA < 80 and PRA > 80. Patients with PRA > 25 had decreased survival compared with those with PRA < 25 after listing (P = 0.004). There was an even greater difference in survival between patients with PRA > 80 and those with PRA < 80 (P = 0.002). Similar analyses for the patients who underwent successful transplantation showed no significant difference in post-transplant survival between patients with a pre-transplant PRA > 25 and those with PRA < 25 (P = 0.23). A difference approaching significance was noted for patients with PRA > 80 compared with PRA < 80 (P = 0.066). Patients with significantly elevated pre-transplant PRAs at the time of listing have a significantly worse outcome compared to those with moderately increased PRA values or non-sensitized patients. Further study is necessary to guide physician and family treatment decisions at the time of listing.     

Outcomes in pediatric cardiac transplantation with a positive HLA cross-match

Richmond ME, Hsu DT, Mosca RS, Chen J, Quaegebeur JM, Addonizio LJ, Lamour JM. Outcomes in pediatric cardiac transplantation with a positive HLA cross‐match.
Pediatr Transplantation 2012: 16: 29–35. © 2011 John Wiley & Sons A/S. Abstract: Previous studies have shown poor outcomes in pediatric heart transplant recipients with a high PRA or a positive direct donor–recipient cross‐match. This study describes outcomes in patients with a positive cross‐match at a large pediatric program. Pediatric heart transplant patients at a large single center between January 1993 and July 2009 were reviewed; those with cross‐match data were analyzed. Cross‐match data were available in 242/262 (92.4%) patients. Indications for transplant were cardiomyopathy (58%), CHD (32%), and retransplant (7%). PRA was ≥10% in 31/213 (14.6%) patients. A retrospective cross‐match was positive in 17/31 (55%) patients with PRA ≥10% and 0/182 with PRA <10%. In positive cross‐match patients, rejection frequency in the first year post‐transplant was higher than negative cross‐match patients (1.69 vs. 0.96 episodes/pt year, p = 0.014). There was no difference in rejection frequency after the first year post‐transplant (0.18 vs. 0.12 episodes/pt year, p = 0.14). Overall survival was not significantly different between the groups with a median follow‐up time of 4.5 yr. Heart transplantation in patients with a positive cross‐match may result in good medium‐term survival but a higher frequency of early rejection. Further investigation is warranted to define which patients with a positive cross‐match will do poorly.     

Clinical significance of anti‐HLA antibodies associated with ventricular assist device use in pediatric patients: A United Network for Organ Sharing database analysis

While VAD use in pediatric patients has previously been associated with anti‐HLA antibody production, the clinical significance of these antibodies is unclear. We investigated the clinical impact of anti‐HLA antibodies associated with VAD use in a large cohort of pediatric HTx recipients. From 2004 to 2011, pediatric cardiomyopathy patients post‐HTx (N=1288) with pre‐HTx PRA levels were identified from the United Network for Organ Sharing database. PRA levels were compared between VAD patients and those with no history of MCS. Incidence of rejection and overall survival were compared between VAD and non‐MCS groups after stratification by PRA and age. VAD recipients were more likely to produce anti‐HLA antibodies than non‐MCS patients (25.5% vs 10.5% had PRA>10%, P<.0001). Sensitized VAD patients (PRA>10%) had a higher incidence of rejection within 15 months of HTx compared to sensitized non‐MCS patients (57.1% vs 35.9%, P=.02). There was no intergroup difference in 15‐month mortality. Among pediatric cardiomyopathy patients supported with a VAD, the presence of anti‐HLA antibodies prior to HTx is associated with an increased risk of rejection. The mechanism of the association between VAD‐associated antibodies and early rejection is unclear and warrants further investigation.     

Detection of graft fibrosis by vibration‐controlled transient elastography in pediatric liver transplant recipients

Pediatric liver transplant recipients are at risk of developing graft fibrosis which can affect patient survival. VCTE is a non‐invasive tool that measures LSM and has been shown to correlate with hepatic fibrosis. The aim of this study was to therefore evaluate the ability of LSM to predict fibrosis in pediatric liver transplant recipients with different graft types. We performed a cross‐sectional study evaluating LSM of 28 pediatric liver transplant recipients who underwent a total of 20 liver biopsies within 1 month of LSM. LSM was compared to liver histology as well as graft type: WL or PL. The median LSM of all post‐transplant patients was 5.6 kPa (range = 2.7‐18.3). There was a statistically significant correlation between LSM and METAVIR fibrosis score (P = .001) and LAF score (P < .001). There was no difference in LSM between graft type (P = .088). The AUROC curve for LSM predicting any significant fibrosis (F ≥ 2) was 0.863. A cutoff value of 7.25 had a sensitivity of 71%, specificity of 100%, NPV of 87%, and PPV of 100% for significant fibrosis. LSM by VCTE is feasible in pediatric liver transplant recipients regardless of graft type. We found a significant correlation between LSM and hepatic fibrosis and established a cutoff value that may help determine which patients warrant further evaluation for graft fibrosis.     

Allosensitization does not alter post‐transplant outcomes in pediatric patients bridged to transplant with a ventricular assist device

Patients supported with a VAD are at increased risk for sensitization. We aimed to determine risk factors for sensitization as well as the impact of sensitization on post‐transplant outcomes. The UNOS database (January 2004–June 2014) was used to identify patients (≤18 yrs) supported with a durable VAD. Rates and degree of sensitization in the VAD cohort were calculated. Post‐transplant survival was determined comparing outcomes of sensitized vs. non‐sensitized patients. There were 3097 patients included in the study; 19% (n = 579) were bridged with a VAD. Of these, 41.8% were sensitized vs. 29.9% of the patients who were not bridged with a VAD (p < 0.001). VAD was an independent predictor of sensitization (OR 2.05 [1.63–2.57]; p < 0.001). There was no difference in sensitization based on device type (continuous vs. pulsatile flow, p = 0.990). Post‐transplant survival rates between the sensitized and non‐sensitized VAD patients were not different, including patients with a PRA >50% and VAD patients with a positive DSC (p = 0.280 and 0.160, respectively). In conclusion, pediatric VAD patients are more likely to be sensitized, but there was no difference in sensitization based on device type. In addition, sensitization does not appear to impact outcomes.     

Outcomes in pediatric hepatitis C transplant recipients: Analysis of the UNOS database

HCV may lead to the development of ESLD in late childhood and, consequently, contributes to the need for liver transplantation. The aim of this study was to examine post‐transplant outcomes in HCV‐positive pediatric patients with ESLD from any cause and to determine the impact of the PELD scoring system, introduced in February 2002, on post‐transplant patient and graft survival. A retrospective analysis of the UNOS database from 1994 to 2010 was performed to assess graft and patient survival in pediatric HCV‐seropositive liver transplant recipients. Graft survival and patient survival comparing subjects in the pre‐PELD era and post‐PELD era were analyzed using Kaplan–Meier statistics. Factors associated with survival were identified using Cox regression analysis. Of 120 pediatric HCV transplant recipients, 80 were transplanted in the pre‐PELD era and 40 were transplanted post‐PELD. Median serum total bilirubin, INR, and creatinine were 4.8 mg/dL, 1.6, and 0.7 mg/dL in the pre‐PELD era vs. 5.5 mg/dL, 1.7, and 0.6 mg/mL, respectively, in the post‐PELD era (p NS). One‐yr graft survival in the pre‐PELD vs. post‐PELD era was 65.0% and 89.7%, respectively (p < 0.01); corresponding three‐yr graft survival was 57.3% vs. 76.2% (p = 0.04). One‐yr patient survival in the pre‐PELD vs. post‐PELD era was 79.0% and 97.5%, respectively (p < 0.01); corresponding three‐yr survival was 79.0% vs. 89.4% (p = 0.17). Twenty‐eight patients (23.3%) were retransplanted: 24 (30%) in the pre‐PELD era (median time to retransplant 272 days) and four (10%) in the post‐PELD era (median time to retransplant 586 days). Early follow‐up demonstrates a trend toward improved pediatric HCV liver transplant graft and patient survival in the post‐PELD era. Superior outcomes may be attributed to pretransplant factors, improved surgical technique and better treatment options for HCV infection.     

Is there an optimal organ acceptance rate for pediatric heart transplantation: “A sweet spot”?

Despite a limited supply of donors, potential donor hearts are often declined for subjective concerns regarding organ quality. This analysis will investigate the relationship between donor heart AR and patient outcome at pediatric transplant centers. The UNOS database was used to identify all match runs for pediatric candidates (age < 18 years) from 2008 through March 2015 in which a heart offer was ultimately placed. Centers which received ≥10 offers/y were included (10 634 offers, 38 centers). Transplant centers were stratified based on their AR: low (<20%, n = 13), medium (20%‐40%, n = 16), or high (>40%, n = 9). Low AR centers experienced worse negative WL outcome compared with medium (P = .022) and high (P = .004) AR centers. Low AR centers had similar post‐transplant graft survival to medium (P = .311) or high (P = .393) AR centers; however, medium AR centers had better post‐transplant graft survival than high AR centers (P = .037). E‐F survival from listing regardless of transplant was worse for low AR centers compared with medium (P < .001) or high (P = .001) AR centers. Low AR centers experience worse WL outcomes without improvement in post‐transplant outcomes. High AR centers experience higher post‐transplant graft failure than medium AR centers. AR of 20%‐40% appears to have optimal WL and post‐transplant outcomes.     

Donor‐specific anti‐HLA antibody production following pediatric ABO‐incompatible heart transplantation

ABO‐i heart transplantation can be performed in infants with end‐stage heart failure to increase organ availability. The development of newly detected DSAs is associated with decreased cardiac graft survival, and the effect of ABO‐i transplantation on DSA production is unknown. We examined DSA production and rejection frequency in infant recipients of ABO‐i and ABO‐c heart transplants via a retrospective cohort study of infant heart transplant recipients transplanted at a single pediatric center between January 2004 and November 2014. Patients were included if they were less than 1 year of age at transplant and had a minimum of 6 months follow‐up. DSA positivity was examined under two categories, either the lowest level detectable (MFI > 500) or a level presumed to have clinical relevance in our immunogenetics laboratory (MFI > 5000). Of 52 patients, 36 received ABO‐c transplants and 16 received ABO‐i transplants. Compared to ABO‐c recipients, the ABO‐i group showed a consistent but statistically non‐significant finding of less frequent ndDSA positivity (69.4% ABO‐c vs 43.8% ABO‐i with MFI >500, P = 0.122; 41.7% ABO‐c vs 25% ABO‐i with MFI >5000, P = 0.353). Additionally, ABO‐i patients were less likely to have any form of rejection (12.5% vs 47.2%, P = 0.027) or acute cellular rejection (6.3% vs 38.9%, P = 0.021). Our data suggest that infants receiving ABO‐i heart transplants may be less likely to develop ndDSAs or have rejection compared to same age ABO‐c recipients. Larger multicenter studies are needed to confirm results from this single center study.     

Kidney transplant in pediatric patients with severe bladder pathology

The aim of the current study was to compare results in pediatric renal transplantation of patients with and without SBP. Between 2001 and 2013, a total of 168 kidney transplants were performed at our center. A retrospective analysis was performed and recipients were divided into two groups: NB and SBP. Incidence of surgical complications after procedure, and graft and patient survival were evaluated. A total of 155 recipients (92%) with complete data were analyzed, and 13 recipients that had had previous bladder surgeries were excluded (11 with VUR surgery and two with previous kidney transplants), of the 155 recipients: 123 (79%) patients had NB, and 32 (21%) patients had SBP, with a median follow‐up of 60 (1–137) and 52 (1–144) months, respectively. Among post‐transplant complications, UTI (68.8% vs. 23%, p < 0.0001) and symptomatic VUR to the graft (40.6% vs. 7.3%, p < 0.0001) were significantly higher in the SBP group. There was no significant difference in overall graft and patient survival between groups. Renal transplantation is safe in pediatric recipients with SBP; however, urologic complications such as UTI and VUR were significantly higher in this group. Graft and patient survival was similar in SBP and NB groups.     

20‐ to 25‐year patient and graft survival following a single pediatric liver transplant—Analysis of the United Network of Organ Sharing database: Where to go from here

To understand factors contributing to liver graft loss and patient death, we queried a national database designed to follow pediatric patients transplanted between 1987 and 1995 till adulthood. A comparison was made to a cohort transplanted between 2000 and 2014. The 5‐, 10‐, 15‐, 20‐, and 25‐year patient survival and graft survival were 95.5%, 93.7%, 89.1%, 80.8%, and 73.1%, and 92.5%, 86.7%, 77.6%, 68.7%, and 62.2%, respectively. The twenty‐year patient/graft survival was significantly worse in those transplanted between 5 and 17 years of age compared to those transplanted at <5 years of age (P < 0.001). For the modern era cohort, the 3‐year patient survival was significantly lower in children transplanted at 16‐17 years of age compared to those transplanted at <5 and 11‐15 years of age (P ≤ 0.02). The 3‐year graft survival was similarly lower in children transplanted at 16‐17 years of age compared to those transplanted at <5, 5‐10, and 11‐15 years of age (P ≤ 0.001). Infection as a cause of death occurred either early or >15 years post‐transplant. Chronic rejection remained the leading cause of graft loss in both cohorts and the commonest indication for retransplantation 20‐25 years following primary transplant. Further research is required to identify modifiable factors contributing to development of chronic rejection.     

Predictors of cardiac allograft vasculopathy in pediatric heart transplant recipients

CAV remains a leading cause of late graft loss and mortality among survivors of pediatric heart transplantation. We sought to define the incidence of CAV and identify its predictors in pediatric heart transplant recipients. The OPTN/UNOS database was analyzed for pediatric recipients who underwent heart transplant between 1987 and 2011. The primary end‐point is time from heart transplantation to development of CAV (CAV‐free survival). To identify predictors of CAV‐free survival, demographic and transplant data were analyzed by the Kaplan–Meier survival method and Cox proportional hazards regression. Of 5211 pediatric heart transplant recipients with at least one‐yr follow‐up, the incidence of CAV at five, 10, and 15 yr was 13%, 25%, and 54%, respectively. Multivariate analysis found that risk of CAV was associated with the following variables: Recipient age 1–4 yr (HR 1.25), 5–9 yr (1.45), 10–18 yr (1.83), donor age >18 yr (1.34), re‐transplantation (2.14), recipient black race (1.55), and donor cigarette use (1.54). Older recipient and donor age, recipient black race, donor cigarette use, and re‐transplantation were highly associated with shorter CAV‐free survival.     

Neutropenia in pediatric heart transplant recipients

Neutropenia has been reported in pediatric heart transplant recipients, but its association with infectious morbidity and mortality is unknown. We sought to determine neutropenia's prevalence and impact on infection, rejection, and survival. A retrospective analysis of pediatric heart transplant recipients from March 2005 to August 2015 was performed. Demographics, medications, infection, and rejection data were collected. Of 142 pediatric heart transplant recipients, 77 (54.2%) developed neutropenia within 4.7 months [3.3‐12.1 months] of transplant. In all patients, the adjusted 5‐year cumulative incidence of neutropenia was 30.2%. Fifty‐one patients (66.2%) had recurrent neutropenia. Six of 14 tested had positive antineutrophil antibodies. Medications associated with neutropenia were decreased in 15 (19.5%) and discontinued in 42 (54.4%) patients with no change in 1‐year rejection rates compared to published data. Fifteen patients developed infection within 30 days of neutropenia and two from 30 days to 1 year, with an infection rate similar to the non‐neutropenic group. There was no significant difference in survival, ANC, rate of rejection or PTLD in neutropenic patients with and without infection at median follow‐up (5.5 years). Neutropenia is common in pediatric heart transplant recipients. Neutropenia had <20% risk of associated infection, similar to non‐neutropenic patients. Infection in neutropenic patients did not increase mortality.     

Assessment of prophylactic heparin infusion as a safe preventative measure for thrombotic complications in pediatric kidney transplant recipients weighing <20 kg

Small‐sized kidney recipients (<20 kg) are at high risk of allograft vessel thrombosis. HP has been used to mitigate this risk but may infer an increase in bleeding risks. Therefore, we aim to determine whether HP is a safe means to prevent thrombosis in small kidney transplant patients by comparing those who have received HP and those who have NHP. A retrospective review of patients < 20 kg who underwent kidney transplant in our institution from 2000 to 2015 was performed. At our institution, unfractionated heparin 10 units/kg/hour is used as HP since 2009. Patients at increased risk of thrombosis (previous thrombosis, thrombophilia, nephrotic syndrome) and bleeding (therapeutic doses of heparin, diagnosis of coagulopathy) were excluded. Fifty‐six patients were identified (HP n = 46; NHP n = 10). Baseline demographics were similar between HP and NHP. There was no statistical difference in frequency of transfusions, surgical re‐exploration, or thrombotic events between HP and NHP. The HP group was more likely to have drop in Hb > 20 g/L (67.4% vs 30.0%, P = 0.038), and those who had drop in Hb > 20 g/L were more likely to also require pRBC transfusions (63.0% vs 20.0%, P = 0.017). Within the HP group, those who had bleeding complications had similar Hb levels as those who did not at baseline and post‐transplant. Outcomes in the HP and NHP groups were no different with respect to thrombosis or significant bleeding complications requiring pRBC transfusions or surgical intervention. Future prospective studies are required to investigate the balance of preventing thrombosis and risks of pRBC transfusions for small‐sized kidney recipients.     

Impact of donor preprocurement cardiac arrest on clinical outcomes in pediatric deceased donor liver transplantation

PPCA has historically been considered detrimental to donor quality in LT, but transplantation of grafts from this group of donors is now routine. Our study aims to evaluate the outcomes associated with use of donors with a history of PPCA in the pediatric population. This study is a single‐center retrospective analysis of all pediatric LTs performed over an 18‐year period. Donors and recipients were stratified by the presence and length of donor PPCA time. Preprocurement donor and post‐transplant recipient laboratory values were collected to assess the degree of ischemic liver injury associated with each donor group. Cox regression analysis was used to compare survival. The records for 130 deceased pediatric LT donors and corresponding recipients were reviewed. There were 73 (56%) non‐PPCA donors and 57 (44%) PPCA donors. Donors that experienced a PPCA event demonstrated a higher median, pretransplant peak alanine aminotransferase (ALT) level (P < .001). When comparing post‐transplant recipient median ALT levels, donors with any PPCA had lower median peak ALT (P = .15) and day 3 ALT (P = .43) levels than the non‐PPCA group. Rates of early graft loss did not differ. The PPCA group with >40 minutes of ischemia had markedly lower survival at 10 years, but this finding did not reach statistical significance. Liver grafts from donors with or without PPCA demonstrated no statistically significant differences in function or survival. A history of donor PPCA alone should not be used as an exclusionary criterion in pediatric liver transplantation.     

Incidence and risk factors of early surgical complications in young renal transplant recipients: A persistent challenge

There is a paucity of data on the rate of urological and vascular complications in very young children after kidney transplant. We conducted a study on the incidence and risk factors for early post‐transplant surgical complications in young recipients (<5 years) over three decades. The primary outcome was any urological or vascular complication within 30 days of transplant, and the secondary outcome was incidence rate of graft failure reported as per 1000 person‐years. Risk factors associated with surgical complications were analyzed by logistic regression. There were 22 (26.5%) complications in 21 children with vascular thrombosis being the most common complication. There was no significant difference in the number of complications in period 1 (1985‐1994) and period 2 (1995‐2014) (P=.1). The incidence rate of graft failure was higher in period 1 (IR 70.8, 95% CI 41.1, 121.9) compared to period 2 (IR 20.7, 95% CI 9.3, 46.0). Cumulative incidence of graft survival at 1, 3, and 5 years' post‐transplant was 96.5%, 92.6%, and 90%, respectively, in those without compared to 71%, 65.1%, and 58.6%, respectively, in children with complications. In conclusion, early surgical, especially vascular, complications are quite common in young renal transplant recipients and lead to significantly reduced graft survival.     

Analysis of rabbit anti‐thymocyte globulin vs basiliximab induction in pediatric liver transplant recipients

Literature is limited comparing induction immunosuppression in pediatric liver transplant (LTx) recipients. This is a single‐center, retrospective cohort study of primary pediatric liver transplants at our center between 2005 and 2016 who received either basiliximab (BSX) or rabbit anti‐thymocyte globulin (rATG) induction. Maintenance immunosuppression consisted of tacrolimus ± a corticosteroid taper. Exclusions included receipt of an ABO‐incompatible graft, retransplantation, and multi‐organ transplantation. Primary outcomes were incidence of treated biopsy‐proven acute rejection (tBPAR) and PTLD within the first year and infections within 90 days of LTx. Secondary outcomes included graft and patient survival, time to first tBPAR, and incidence of steroid‐resistant rejection (SRR) within the first year post‐LTx. A total of 136 patients were included in the final analysis of which 57 patients (42%) received BSX induction. Patients who received rATG induction with or without a 2‐week corticosteroid taper experienced significantly more tBPAR compared to those who received BSX induction with a 6‐month corticosteroid taper (55.7% vs 33.3%, P = .01). There were no differences in the incidence of PTLD, infections, SRR, graft or patient survival, or time to first tBPAR between the two groups . Induction with rATG either with or without a short corticosteroid taper was associated with significantly more tBPAR in primary pediatric LTx recipients when compared to BSX induction with a prolonged corticosteroid taper in the setting of maintenance immunosuppression with tacrolimus.     

Role of race in kidney transplant outcomes in children with focal segmental glomerulosclerosis

It is well established that racial differences exist in kidney transplant outcomes; however, there are no studies which focus on the role of race in transplant outcomes specifically in children diagnosed with FSGS. Associations between race and transplant outcomes in FSGS children were evaluated using the Organ Procurement and Transplantation Network database from 2000 to 2012. Recipients aged 2–21 years who received a kidney‐only transplant were included. Multivariate regression models were used to evaluate transplant outcomes by race. Five hundred and thirty‐six recipients (59.7% male, 15.6±3.9 years) were black and 1134 (55.7% male, 14.3±5.0 years) were non‐black. Graft survival was significantly shorter in the black group (4.2±3.1 vs 4.6±3.3 years, P=.005). Black race was associated with significantly higher risk of graft failure (HR 1.34, 95% CI=1.21–1.49, P<.0001), acute rejection (OR 1.66 95% CI=1.39–1.97, P<.0001), and delayed graft function (OR 1.51, 95% CI=1.33–1.72, P<.001) compared to non‐black race. There were no significant differences in mortality, prolonged hospitalization, or FSGS recurrence between groups. Race is a significant predictor for worse transplant outcomes in children with FSGS.     

Across all solid organs,adolescent age recipients have worse transplant organ survival than younger age children: A US national registry analysis

Univariate analyses suggest that adolescents have worse long‐term allograft survival versus younger children across different SOT. This study's objective was to determine whether multivariate analyses of a large national database recording all deceased SOT (KI; LI; HR; LU) also show worse adolescent allograft survival in the different organs. Using data from the national Scientific Registry for Transplant Recipients in the USA for pediatric primary SOT from 1989 to 2010, we calculated median half‐lives and constructed K–M graft survival curves. Recipient age at transplant (<12 or adolescent 12–17 yr) was fitted with other identical covariates into multivariate Cox proportional hazards models. In all SOT recipients, unadjusted graft survival curves demonstrated better graft survival for adolescents initially, followed by crossing of the lines, such that adolescent SOT recipients had worse survival after one yr (KI), 4.6 yr (LI), 4.4 yr (HR), and 1.6 yr (LU). Multivariate models of the post‐cross period showed a significantly higher AHR for worse graft survival in adolescent age across all four SOTs: AHR 1.400 (KI), 1.958 (LI), 1.414 (HR), and 1.576 (LU). Improving adolescent long‐term outcomes across all four organs will be a defining issue in the future.     

Persistent C4d and antibody‐mediated rejection in pediatric renal transplant patients

Pediatric renal transplant recipient survival continues to improve, but ABMR remains a significant contributor to graft loss. ABMR prognostic factors to guide treatment are lacking. C4d staining on biopsies, diagnostic of ABMR, is associated with graft failure. Persistent C4d+ on follow‐up biopsies has unknown significance, but could be associated with worse outcomes. We evaluated a retrospective cohort of 17 pediatric renal transplant patients diagnosed with ABMR. Primary outcome at 12 months was a composite of ≥50% reduction in eGFR, transplant glomerulopathy, or graft failure. Secondary outcome was the UPCR at 12 months. We used logistic and linear regression modeling to determine whether persistent C4d+ on follow‐up biopsy was associated with the outcomes. Forty‐one percent reached the primary outcome at 12 months. Persistent C4d+ on follow‐up biopsy occurred in 41% and was not significantly associated with the primary outcome, but was significantly associated with the secondary outcome (estimate 0.22, 95% CI 0.19‐0.25, P < .001), after controlling for confounding factors. Persistent C4d+ on follow‐up biopsies was associated with a higher UPCR at 12 months. Patients who remain C4d+ on follow‐up biopsy may benefit from more aggressive or prolonged ABMR treatment.     

Alemtuzumab induction with tacrolimus monotherapy in 25 pediatric renal transplant recipients

ALA induction in transplantation has been shown to reduce the need for maintenance immunosuppression. We report the outcome of 25 pediatric renal transplants between 2007 and 2010 using ALA induction followed by tacrolimus maintenance monotherapy. Patient ages were 1–19 yr (mean 14 ± 4.1 yr). Time of follow‐up was 7–51 months (mean 26 ± 13 months). Tacrolimus monotherapy was maintained in 48% of patients, and glucocorticoids were avoided in 80% of recipients. Mean plasma creatinine and GFR at one yr post‐transplant were 0.88 ± 0.3 mg/dL and 104.4 ± 25 mL/min/1.73m², respectively. One, two, and three‐yr actuarial patient and graft survival rates were 100%. The incidence of early AR (<12 months after transplantation) was 12%, while the incidence of late AR (after 12 months) was 16%. Forty‐four percent of the recipients recovered normal, baseline renal function after an episode of AR, and 44% had persistent renal dysfunction (plasma creatinine 1.0–1.8 mg/dL). One graft was lost four yr after transplantation due to medication non‐compliance. Four (16%) patients developed BK or CMV infection. In our experience, ALA induction with tacrolimus monotherapy resulted in excellent short‐ and mid‐term patient and graft survival in low‐immunologic risk pediatric renal transplant recipients.