The IPTA Nashville consensus conference on post-transplant lymphoproliferative disorders after solid organ transplantation in children: IV-consensus guidelines for the management of post-transplant lymphoproliferative disorders in children and adolescents.

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders (PTLD) after pediatric solid organ transplantation. This report addresses the outcomes of deliberations by the PTLD Management Working Group. A strong recommendation was made for reduction in immunosuppression as the first step in management. Similarly, strong recommendations were made for the use of the anti-CD20 monoclonal antibody (rituximab) as was the case for chemotherapy in selected scenarios. In some scenarios, there is uncoupling of the strength of the recommendations from the available evidence in situations where such evidence is lacking but collective clinical experiences drive decision-making. Of note, there are no large, randomized phase III trials of any treatment for PTLD in the pediatric age group. Current gaps and future research priorities are highlighted.

The IPTA Nashville Consensus Conference on Post-Transplant lymphoproliferative disorders after solid organ transplantation in children: III - Consensus guidelines for Epstein-Barr virus load and other biomarker monitoring.

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders after solid organ transplantation in children. In this report from the Viral Load and Biomarker Monitoring Working Group, we reviewed the existing literature regarding the role of Epstein-Barr viral load and other biomarkers in peripheral blood for predicting the development of PTLD, for PTLD diagnosis, and for monitoring of response to treatment. Key recommendations from the group highlighted the strong recommendation for use of the term EBV DNAemia instead of "viremia" to describe EBV DNA levels in peripheral blood as well as concerns with comparison of EBV DNAemia measurement results performed at different institutions even when tests are calibrated using the WHO international standard. The working group concluded that either whole blood or plasma could be used as matrices for EBV DNA measurement; optimal specimen type may be clinical context dependent. Whole blood testing has some advantages for surveillance to inform pre-emptive interventions while plasma testing may be preferred in the setting of clinical symptoms and treatment monitoring. However, EBV DNAemia testing alone was not recommended for PTLD diagnosis. Quantitative EBV DNAemia surveillance to identify patients at risk for PTLD and to inform pre-emptive interventions in patients who are EBV seronegative pre-transplant was recommended. In contrast, with the exception of intestinal transplant recipients or those with recent primary EBV infection prior to SOT, surveillance was not recommended in pediatric SOT recipients EBV seropositive pre-transplant. Implications of viral load kinetic parameters including peak load and viral set point on pre-emptive PTLD prevention monitoring algorithms were discussed. Use of additional markers, including measurements of EBV specific cell mediated immunity was discussed but not recommended though the importance of obtaining additional data from prospective multicenter studies was highlighted as a key research priority.

The IPTA Nashville consensus conference on Post-Transplant lymphoproliferative disorders after solid organ transplantation in children: II-consensus guidelines for prevention.

The International Pediatric Transplant Association (IPTA) convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorder after solid organ transplantation in children. In this report from the Prevention Working Group, we reviewed the existing literature regarding immunoprophylaxis and chemoprophylaxis, and pre-emptive strategies. While the group made a strong recommendation for pre-emptive reduction of immunosuppression at the time of EBV DNAemia (low to moderate evidence), no recommendations for use could be made for any prophylactic strategy or alternate pre-emptive strategy, largely due to insufficient or conflicting evidence. Current gaps and future research priorities are highlighted.

Primary Transplantation for Congenital Heart Disease in the Neonatal Period: Long-term Outcomes.

BACKGROUND: Primary transplantation was developed in the 1980s as an alternative therapy to palliative reconstruction of uncorrectable congenital heart disease. Although transplantation achieved more favorable results, its utilization has been limited by the availability of donor organs. This review examines the long-term outcomes of heart transplantation in neonates at our institution. METHODS: The institutional pediatric heart transplant database was queried for all neonatal heart transplants performed between 1985 and 2017. Follow-up was obtained from medical records and an annually administered questionnaire. Overall survival and time to development of complications were estimated using the Kaplan Meier method. Univariate and multivariate analyses were performed to identify independent predictors of survival. RESULTS: Heart transplantation was performed in 104 neonates. Median age was 17 days. Hypoplastic left heart syndrome (classic or variant) was the primary diagnosis in 77.8% of patients. Survival at 10 years and 25 years was 73.9% and 55.8%, respectively. At 20 years, freedom from allograft vasculopathy and lymphoproliferative disease was 72.0% and 81.9%, respectively. Freedom from re-transplantation was 81.4% at 20 years. Eight patients (7.6%) developed end-stage renal disease. By multivariate analysis, lower glomerular filtration rate and allograft vasculopathy were the only significant predictors of death. CONCLUSIONS: Neonatal heart transplantation remains a durable therapy with very acceptable long-term survival. Children transplanted in the newborn period have the potential to reach adulthood with minimal need for reintervention.

Heart transplantation for congenital heart disease in the first year of life.

Successful infant heart transplantation has now been performed for over 25 years. Assessment of long term outcomes is now possible. We report clinical outcomes for322 patients who received their heart transplant during infancy. Actuarial graft survival for newborn recipients is 59% at 25 years. Survival has improved in the most recent era. Cardiac allograft vasculopathy is the most important late cause of death with an actuarial incidence at 25 years of 35%. Post-transplant lymphoma is estimated to occur in 20% of infant recipients by25 years. Chronic kidney disease grade 3 or worse is present in 31% of survivors. The epidemiology of infant heart transplantation has changed through the years as the results for staged repair improved and donor resources remained stagnant. Most centers now employ staged repair for hypoplastic left heart syndrome and similar extreme forms of congenital heart disease. Techniques for staged repair, including the hybrid procedure, are described. The lack of donors is described with particular note regarding decreased donors due to newer programs for appropriate infant sleep positioning and infant car seats. ABO incompatible donors are a newer resource for maximizing donor resources, as is donation after circulatory determination of death and techniques to properly utilize more donors by expanding the criteria for what is an acceptable donor. An immunological advantage for the youngest recipients has long been postulated, and evaluation of this phenomenon may provide clues to the development of accommodation and/or tolerance.

Cause of death in pediatric and infant heart transplant recipients: review of a 20-year, single-institution cohort.

BACKGROUND: As infant and pediatric heart transplantation becomes more common, there is a growing need to better understand the causes of failure or death, if we are to continue to improve the outcome in these children. METHODS: A multidisciplinary team reviewed all deaths occurring in the cohort of infants and children transplanted during the first 20 years of the Loma Linda Pediatric Heart Transplant program, with 2 additional years of follow-up beyond the 20-year accrual period, and classified them as to cause. RESULTS: There were 169 deaths among 421 recipients, with a median follow-up of 9.7 years. Autopsy was performed in 128 cases. The causes of death, in decreasing order of frequency, included acute rejection (26.0%), infection (16.0%), cardiac allograft vasculopathy (CAV) (14.2%), technical issues (8.3%), acute graft dysfunction (6.5%), neoplasm (7.1%), chronic graft dysfunction (4.7%) and miscellaneous factors (10.1%), and in twelve deaths (7.1%) the cause was unclassified. Acute graft dysfunction and technical issues accounted for nearly two-thirds of the deaths in the first 30 days after transplant, while acute rejection resulted in the largest number of deaths after the first year (30.4%), with CAV a close second (23.5%). CONCLUSIONS: Acute graft dysfunction and technical issues were the most frequent cause of early death. Late deaths were most often due to acute rejection and CAV, which differs somewhat from the experience reported in adults. Acute rejection was the single most important cause of late mortality, and resulted in a significant number of late sudden and unexpected deaths.

Pediatric transplantation using hearts refused on the basis of donor quality.

BACKGROUND: There is always more demand than supply of organs in pediatric heart transplantation. Yet, potential donor organs are regularly declined for a variety of reasons, among them donor organ quality as determined by United Network for Organ Sharing (UNOS) refusal code 830 or its equivalent. METHODS: For the study group institutional and UNOS databases (July 2000 to December 2008) were reviewed to examine outcomes of pediatric heart transplantation using donor hearts that had been previously refused one or more times because of organ quality. Variation between outcomes of this cohort and recipients who received primarily offered heart grafts in a single institution was analyzed. RESULTS: In 29 recipients, transplantation or retransplantation was with heart grafts previously declined on the basis of quality. Recovery distances (p < 0.002) and graft cold ischemic times (p < 0.001) were significantly longer for declined hearts. Operative survival was 93% +/- 5.0% (27 of 29). Seven-year actuarial survival was 74% +/- 10.5%. At the present time, 24 of the 29 recipients (83%) are alive. These results do not vary statistically from those experienced by 84 recipients of 86 primarily offered donor organs during the same time. CONCLUSIONS: Despite longer distance recovery (ie, longer graft cold ischemic times), outcomes of pediatric heart transplantation using donor heart grafts refused on the basis of organ quality are highly competitive. Pediatric donor hearts should seldom be declined on the basis of organ quality (UNOS code 830).

Decreased exercise performance with age in children with hypoplastic left heart syndrome.

OBJECTIVE: Children born with hypoplastic left heart syndrome (HLHS) may experience cardiac dysfunction after staged surgery or transplantation, which may worsen with age. We examined the hypothesis that exercise testing can address cardiovascular capacity and suggest interventions to improve quality of life. STUDY DESIGN: Children with HLHS > or = 8 years old performed treadmill or bicycle ergometric testing at 4 centers. Results were compared with norms for age and sex. RESULTS: Of the 42 participants, the mean age was 12.9 years (range, 8.5-17.0 years), 64% were boys, 20 had staged surgery, and 34 completed metabolic assessment. The percent of predicted maximal oxygen uptake (mVO2) was higher in younger children. Children aged 8 to 12 years achieved 70% of predicted mVO2; children aged 13 to 17 years achieved 60% of predicted mVO2 (P = .02). The percent of predicted peak heart rate trended higher in younger patients (83% versus 75%, P = .07). Electrocardiographic changes were more common in older children. In treadmill testing, patients who had a transplant had better exercise performance than patients who underwent staged surgery in percent of predicted exercise time (82% versus 54%, P < .0001) and peak rate-pressure product (241 x 10(3) versus 195 x 10(3), P = .02). The percent of predicted mVO2 did not differ between patients who had a transplant (66%) and patients who underwent staged surgery (61%, P = .25). CONCLUSION: Children with HLHS showed considerable age-related decline in exercise performance, regardless of surgical strategy.

Geometric disproportion of cardiac structure and graft ischemia affect tricuspid valve regurgitation early after neonatal heart transplantation.

BACKGROUND: Although tricuspid valve regurgitation (TR) after heart transplantation is a known complication, there has been little discussion of this subject in neonatal heart transplantation. We aim to elucidate the prevalence, etiology, and evolution of TR early after transplant in neonates. METHODS: Eighty-five neonatal recipients were studied retrospectively by two-dimensional and Doppler echocardiography. The semiquantitative grading of TR was based on the ratio of regurgitation jet area to right atrial area. RESULTS: Immediately after neonatal heart transplantation, TR was recognized in 47 patients (grade 1, n = 18; grade 2, n = 22; grade 3, n = 7; and grade 4, n = 0). Tricuspid regurgitation prevalence diminished from 55% to 19% with reduction in severity 1 year after transplantation. The prevalence of TR (grade 2 and grade 3) was affected by a donor/recipient body weight ratio of more than 2.0 (p = 0.004) and graft ischemia for more than 3 hours (p = 0.014). The ratio of donor and recipient right atria portion, which had a correlation with donor/recipient body weight ratio (r2 = 0.415, p < 0.0001), separated the four subgroups in terms of TR grade immediately after transplantation (p = 0.0064) and also at 1 year after transplantation in all surviving grafts from 1.48 +/- 0.54 to 0.8 +/- 0.32 (p < 0.0001). The Cox model found no significance for early posttransplant TR as a risk factor for graft survival. CONCLUSIONS: Early posttransplant TR was affected by atria geometrical disproportion and by graft ischemia. Tricuspid regurgitation was not a risk factor for graft survival because of its amelioration over time, perhaps induced by recipient growth and recovery of myocardial injury relating to graft procurement.

Relationship of surgical approach to neurodevelopmental outcomes in hypoplastic left heart syndrome.

OBJECTIVE: Two strategies for surgical management are used for infants with hypoplastic left heart syndrome (HLHS), primary heart transplantation and the Norwood procedure. We sought to determine how these 2 surgical approaches influence neurodevelopmental outcomes at school age. METHODS: A multicenter, cross-sectional study of neurodevelopmental outcomes among school-aged children (>8 years of age) with HLHS was undertaken between July 2003 and September 2004. Four centers enrolled 48 subjects, of whom 47 completed neuropsychologic testing. Twenty-six subjects (55%) had undergone the Norwood procedure and 21 (45%) had undergone transplantation, with an intention-to-treat analysis. The mean age at testing was 12.4 +/- 2.5 years. Evaluations included the Wechsler Abbreviated Scale of Intelligence, Clinical Evaluation of Language Fundamentals, Wechsler Individual Achievement Test, and Beery-Buktenica Developmental Test of Visual-Motor Integration. RESULTS: The mean neurocognitive test results were significantly below population normative values. The mean full-scale IQ for the entire cohort was 86 +/- 14. In a multivariate model, there was no association of surgical strategy with any measure of developmental outcome. A longer hospital stay, however, was associated significantly with lower verbal, performance, and full-scale IQ scores. Aortic valve atresia was associated with lower math achievement test scores. CONCLUSIONS: Neurodevelopmental deficits are prevalent among school-aged children with HLHS, regardless of surgical approach. Complications that result in prolonged hospitalization at the time of the initial operation are associated with neurodevelopmental status at school age.

Lessons learned from the pediatric heart transplant study.

The Pediatric Heart Transplant Study (PHTS) group was founded in 1991 as a voluntary, collaborative effort dedicated to the advancement of the science and treatment of children following listing for heart transplantation. Since 1993, the PHTS has collected data in an international, prospective, event-driven database that examines risk factors for outcome events following listing for transplantation. The events include transplantation, death, rejection, infection, malignancy, graft vasculopathy, and retransplantation. Over its 12 years of existence, the PHTS has made major contributions to the field of pediatric heart transplantation, especially in the areas of outcome analysis and risk factor assessment for death and other major morbidities after listing and after transplantation. The new challenges facing the PHTS include how to implement the practice of evidence-based medicine in the field of pediatric heart transplantation and how to support ongoing data collection and analysis to provide long-term outcomes as the PHTS subjects enter their second decade after transplantation.

Effect of oversizing cardiac allografts on survival in pediatric patients with congenital heart disease.

BACKGROUND: There are few published data regarding the long-term outcome of "large" cardiac allografts in children. This study examines the effect of cardiac graft oversizing on the survival of pediatric patients with congenital heart disease (CHD). METHODS: Two hundred ninety-one children, age 1 day to 17 years (median 50 days), with CHD underwent primary cardiac transplantation between 1985 and 2002. Patients were analyzed according to donor-recipient weight ratio (D-R): Group (Gp) I (n = 252) with D-R <2.5 (range 0.59 to 2.49, median 1.4), and Gp II (n = 39) with D-R >/=2.5 (range 2.5 to 4.65, median 2.78). CHD diagnoses included hypoplastic left heart syndrome (138 in Gp I, 13 in Gp II), single ventricle (29 in Gp I, 1 in Gp II) and other (85 in Gp I, 13 in Gp II). Patients with cardiomyopathy were excluded. Pre-transplant cardiac palliation was performed in 36% of Gp I and 15% of Gp II patients. The average graft ischemic times (minutes) were 266 +/- 7.5 and 283 +/- 18.9 for Gp I and Gp II, respectively (p < 0.2). RESULTS: The operative mortality for Gp I was 10.3% and 10.2% for Gp II (p < 0.99). There was no significant difference between the 2 groups in length of hospital stay (p < 0.15) or duration of ventilator support (p < 0.6) post-transplantation. However, the incidence of open chest was higher (p < 0.003) in Gp II (28%) compared with Gp I (8%). The survival rates for Gp I and Gp II were: 82 +/- 2.4% vs 84 +/- 5.7% at 1 year; 71 +/- 2.9% vs 72 +/- 7.2% at 5 years; and 63 +/- 3.2% vs 65% +/- 7.4 at 10 years. CONCLUSIONS: Post-transplant morbidity and short- and long-term survival of pediatric recipients with CHD are not adversely influenced by the use of oversized cardiac allografts.

Moderate acute rejection detected during annual catheterization in pediatric heart transplant recipients.

BACKGROUND: Acute rejection commonly occurs within the first year after heart transplantation, and then decreases in frequency with time. Recently, the long-term utility of endomyocardial biopsy during routine annual catheterization has been questioned. The purpose of this study was to retrospectively review the prevalence of biopsy-proven rejection during routine annual catheterization in our patient population, determine whether biopsies late after transplant are useful, and identify factors that correlate with late unsuspected rejection. METHODS: Biopsy results from the annual catheterization were evaluated from 1986 to August 2000. The prevalence of moderate rejection was evaluated and compared with the patient's immunosuppressive regimen; the prevalence of late rejection; and how late rejection correlated with recipient age, number of first-year rejections and presence of sub-therapeutic cyclosporine. RESULTS: A total of 1108 biopsies were performed in 269 children with a mean follow-up of 5 +/- 3 years (median 5 years, range 1 to 11 years). Three-drug immunosuppressive therapy, including steroids, was used in 93 patients. There was a persistent 8% to 10% prevalence of moderate rejection at up to 10 years post-transplantation. Moderate rejection was more likely in patients: (1). on 3-drug immunosuppressive therapy; (2). with a recipient age >1 year; and (3). with a relatively lower cyclosporine level. CONCLUSIONS: These data suggest that continued surveillance of pediatric transplant patients for acute rejection is indicated for long-term follow-up.

Usefulness of cardiac transplantation in children with visceral heterotaxy (asplenic and polysplenic syndromes and single right-sided spleen with levocardia) and comparison of results with cardiac transplantation in children with dilated cardiomyopathy.

Surgical mortality is high in children with visceral heterotaxy (VH), particularly if atrioventricular valve insufficiency, ventricular dysfunction, or aortic atresia is present. This study reviews the outcome of cardiac transplantation (CT) in infants and children with VH and congenital heart disease who are at high risk for standard palliative or corrective surgery. We reviewed CT outcomes in 29 children with VH, congenital heart disease, atrioventricular valve insufficiency, ventricular dysfunction, and/or aortic atresia. Median age at CT was 3.1 years. Cardiac surgery had been performed in 20 patients (69%) before CT. Follow-up since CT has been 8.5 +/- 2.2 years. Outcomes were compared with 45 children who underwent transplantation for dilated cardiomyopathy. Actuarial graft survival in the VH group at 30 days and 1, 5, and 10 years was 100%, 86%, 68%, and 50%, respectively, compared with 100%, 96%, 83%, and 68% in children who underwent transplantation for dilated cardiomyopathy (p = 0.12). Splenic status, cardiac position, age at CT, number of prior cardiac surgeries, or systemic venous anomalies were not predictors of mortality after CT. Cardiopulmonary bypass and graft ischemic times were longer in the VH group; time on the ventilator after CT, length of hospitalization, and rejection, infection, post-transplant lymphoproliferative disease, and transplant coronary artery disease rates were equal. Thus, CT is a viable alternative therapy for high-risk patients with VH, possibly offering improved survival over standard surgical management.

Total lymphoid irradiation for refractory rejection in pediatric heart transplantation.

BACKGROUND: We evaluated the role of total lymphoid irradiation (TLI) in the management of refractory rejection among pediatric heart transplant patients. METHODS: Eleven of 298 patients underwent TLI at 6 to 195 months of age and were divided into subgroups: those who survived (group A, n = 7) and those who did not survive beyond 1 year after TLI (group D, n = 4). Non-TLI recipient data were considered as the controls. RESULTS: Six out of 11 patients died eventually (54%). TLI was initiated 3 to 107 months after transplantation with a dosage of 600 to 840 cGy. The pre-TLI rejection rate (0.62 +/- 0.40 per month) was higher (p < 0.0001); however, the post-TLI rejection rate (0.24 +/- 0.65 per month) showed no significant difference from the control rejection rate. The Cox proportional hazard model found significance for TLI as a risk factor for development of posttransplant coronary artery disease (relative risk, 4.8; 95% CI, 1.1 to 21.3) and posttransplant lymphoproliferative disease (relative risk, 47.9; 95% CI, 1.6 to 1,475.3), respectively. Although the rejection rate decreased after TLI in both groups (group A pre/post, 0.51 +/- 0.31/0.06 +/- 0.08 per month; group D pre/post, 0.82 +/- 0.49/0.57 +/- 1.09 per month), significance was obtained only in group A (p = 0.018). CONCLUSIONS: TLI was an effective adjunct for reversal of refractory rejection in pediatric heart transplantation by reducing the rejection rate. Great care must be taken for the risk of development of coronary artery disease or lymphoproliferative disease.