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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. [ABSTRACT FROM AUTHOR]

Most infants and children referred for cardiac transplantation have low cardiac output with concurrent renal hypoperfusion leading to renal insufficiency and failure. This article is a review of the literature of and a single center's experience with combined heart and kidney failure in infants and children less than 10 yr of age. While 39 infants less than 10 yr of age were dialyzed pre- or peri-operatively, none required dialysis support at the time of discharge or in 5–10 yr follow-up. Based on our experience we recommend heart transplant alone in infants and young children with primary heart disease even though they have renal dysfunction. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Simple Summary: Post-transplant lymphoproliferative disorders (PTLD) are heterogenous lymphoproliferative disorders that develop in immunosuppressed transplant recipients. We performed a retrospective review of PTLD occurring in pediatric heart transplant recipients and sought to determine the correlation of PTLD subtypes with different characteristics. Our single institution retrospective study found that compared to older children, infant heart transplant recipients were less likely to develop PTLD. Infant heart transplant recipients who developed PTLD were diagnosed later than older children and had a lower rate of more aggressive PTLD. The overall survival of patients with more aggressive PTLD was significantly lower than patients with low-grade PTLD. Proper classification of the type of PTLD is important, as the subtypes of PTLD showed a significant correlation with the outcome. Post-transplant lymphoproliferative disorders (PTLD) are heterogenous lymphoproliferative disorders that develop as a consequence of immunosuppression in transplant recipients. We sought to determine if subtypes of PTLD correlated with different outcomes. We performed a retrospective review of PTLD occurring in pediatric heart transplant recipients. A total of 558 children and infants underwent cardiac transplantation at our institution between 1985 and 2019 and were followed until March 2021. Forty-nine of 558 patients developed PTLD (8.8%). As compared to older children (>one year of age), infant recipients (

Vascularization of transplanted islets must be maintained to provide long-term graft function. In vivo assessment of new vessel formation in islet grafts has been poorly documented. The purpose of this study was to investigate whether neovascularization was detectable in vivo in a Feridex-labeled murine syngeneic subcapsular islet mass using DCE MRI over 180 days. Subcapsular transplants could be visualized at post-transplant days three, seven, 14, and 28 using T2-weighted MRI and at post-transplant day 180 by immunohistochemistry. Injection of the contrast agent gadolinium (Gd)-DTPA for DCE at three, seven, and 14 days showed increased signal in the transplant area consistent with new vessel formation. Areas under contrast enhancement curves suggested peak angiogenesis at 14 days. At 180 days, there was no observable change in signal intensity after contrast injection suggesting established vascularization or islet mass reduction. Immunohistochemistry confirmed MRI and DCE findings. These data suggest that islet angiogenesis occurs early after transplantation and is likely established after one month of transplantation. This study provides an in vivo time-line of neovascularization in subcapsular islet grafts. We anticipate that contrast extravasation captured by MRI may provide useful monitoring of graft angiogenesis if reproduced in a clinically relevant intraportal model. [ABSTRACT FROM AUTHOR]

To evaluate changes in neovascularization of transplanted islets in vivo, dynamic contrast (gadolinium) enhanced magnetic resonance imaging (MRI) was used. Both iron (Feridex)-labeled and unlabeled syngeneic murine subcapsular islet grafts were studied. Differences in dynamic contrast enhancement of islet grafts were quantified after gadolinium injection at post-transplant days 3 and 14. Normalized contrast concentrations at day 14 in transplanted islets were increased relative with that on day 3. Time to peak contrast enhancement was faster by 12 min at day 14 compared to day 3 islets (while kidney and muscle peak times remained the same). Areas under the curve for contrast concentration versus time plots were larger in 14-day relative to 3-day islet grafts. In conclusion, noninvasive assessment of neovascularization is achievable. In vivo dynamic contrast-enhanced MRI can be used to detect and quantify changes in vascularization following islet transplantation. This technique may be useful in developing pro-angiogenic strategies to improve the transplantation outcome in experimental and clinical settings. [ABSTRACT FROM AUTHOR]

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. [Copyright &y& Elsevier]

Simple Summary: Post-transplant lymphoproliferative disorders (PTLDs) are lymphoid or plasmacytic proliferations that develop in up to 10–15% of immunosuppressed recipients of solid organ transplantation (SOT), bone marrow and/or hematopoietic stem cell allograft. Its prevalence is expected to rise as transplant numbers increase. We performed a single-center retrospective study on the characteristics and outcomes of PTLD at our center in the rituximab era. Infants have been suggested to be a unique population of patients who develop PTLD later due to delayed Epstein–Barr virus (EBV) infection and the presence of maternal antibodies. We found that when compared to older cohorts, infant recipients of SOT had a numerically longer time to PTLD diagnosis. Epstein–Barr virus (EBV) positivity has not been shown to impact survival of patients with PTLD, but we suggest that EBV viral load at time of diagnosis could be investigated further as a marker of survival in patients with EBV-positive PTLD. Post-transplant lymphoproliferative disorders (PTLDs) are lymphoid or plasmacytic proliferations ranging from polyclonal reactive proliferations to overt lymphomas that develop as consequence of immunosuppression in recipients of solid organ transplantation (SOT) or allogeneic bone marrow/hematopoietic stem cell transplantation. Immunosuppression and Epstein–Barr virus (EBV) infection are known risk factors for PTLD. Patients with documented histopathologic diagnosis of primary PTLD at our institution between January 2000 and October 2019 were studied. Sixty-six patients with PTLD following SOT were followed for a median of 9.0 years. The overall median time from transplant to PTLD diagnosis was 5.5 years, with infant transplants showing the longest time to diagnosis at 12.0 years, compared to pediatric and adolescent transplants at 4.0 years and adult transplants at 4.5 years. The median overall survival (OS) was 19.0 years. In the monomorphic diffuse large B-cell (M-DLBCL-PTLD) subtype, median OS was 10.7 years, while median OS for polymorphic subtype was not yet reached. There was no significant difference in OS in patients with M-DLBCL-PTLD stratified by quantitative EBV viral load over and under 100,000 copies/mL at time of diagnosis, although there was a trend towards worse prognosis in those with higher copies. [ABSTRACT FROM AUTHOR]