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Milligan C, Williams RJ, Singh TP, Bastardi HJ, Esteso P, Almond CS, Gauvreau K, Daly KP. Impact of a positive crossmatch on pediatric heart transplant outcomes. J Heart Lung Transplant 2024; 43:963-972. [PMID: 38423415 PMCID: PMC11090719 DOI: 10.1016/j.healun.2024.02.1457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 02/08/2024] [Accepted: 02/21/2024] [Indexed: 03/02/2024] Open
Abstract
BACKGROUND Pediatric heart transplant (HT) candidates experience high waitlist mortality due to a limited donor pool that is constrained in part by anti-HLA sensitization. We evaluated the impact of CDC and Flow donor-specific crossmatch (XM) results on pediatric HT outcomes. METHODS All pediatric HTs between 1999 and 2019 in the OPTN database were included. Donor-specific XM results were sub-categorized based on CDC and Flow results. Primary outcomes were treated rejection in the first year and time to death or allograft loss. Propensity scores were utilized to adjust for differences in baseline characteristics. RESULTS A total of 4,695 pediatric HT patients with T-cell XM data were included. After propensity score adjustment, a positive T-cell CDC-XM was associated with 2 times higher odds of treated rejection (OR 2.29 (1.56, 3.37)) and shorter time to death/allograft loss (HR 1.50 (1.19, 1.88)) compared to a negative Flow-XM. HT recipients who were Flow-XM positive with negative/unknown CDC-XM did not have higher odds of rejection or shorter time to death/allograft loss. An isolated positive B-cell XM was also not associated with worse outcomes. Over the study period XM testing shifted from CDC- to Flow-based assays. CONCLUSIONS A positive donor-specific T-cell CDC-XM was associated with rejection and death/allograft loss following pediatric HT. This association was not observed with a positive T-cell Flow-XM or B-cell XM result alone. The shift away from performing the CDC-XM may result in loss of important prognostic information unless the clinical relevance of quantitative Flow-XM results on heart transplant outcomes is systematically studied.
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Affiliation(s)
- Caitlin Milligan
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - Ryan J Williams
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - Tajinder P Singh
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - Heather J Bastardi
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts
| | - Paul Esteso
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - Christopher S Almond
- Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California
| | - Kimberlee Gauvreau
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts
| | - Kevin P Daly
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts.
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Dipchand AI, Webber SA. Pediatric heart transplantation: Looking forward after five decades of learning. Pediatr Transplant 2024; 28:e14675. [PMID: 38062996 DOI: 10.1111/petr.14675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 11/17/2023] [Accepted: 11/24/2023] [Indexed: 02/07/2024]
Abstract
Heart transplantation has become the standard of care for pediatric patients with end-stage heart disease throughout the world. Since the first transplant was performed in 1967, the number of transplants has grown dramatically with 13 449 pediatric heart transplants being reported to The International Society of Heart and Lung Transplant (ISHLT) between January 1992 and June 30, 2018. Outcomes have consistently improved over the last few decades, specifically short-term outcomes. Most recent survival data demonstrate that recipients who survive to 1-year post-transplant have excellent long-term survival with more than 60% of those who were transplanted as infants being alive 25 years later. Nonetheless, the rates of graft loss beyond the first year have remained relatively constant over time; driven primarily by our poor understanding and lack of treatments for chronic allograft vasculopathy (CAV). Acute rejection, CAV, graft failure, and infection continue to be the major causes of death within the first 5 years post-transplant. In addition, renal dysfunction, malignancy, and the need for re-transplantation remain as significant issues that require close follow-up. Looking forward, key challenges include improving donor utilization rates (including donation after cardiac death (DCD) and the use of ex vivo perfusion devices), the development of non-invasive biomarkers for rejection, efforts to mitigate the long-term effects of immunosuppression, and prevention of CAV. It is not possible to cover the entire evolution of pediatric heart transplantation over the last five decades, but in this review, we hope to touch on key observations, lessons learned, and practice changes that have advanced the field, as well as glance ahead to the next decade.
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Affiliation(s)
- Anne I Dipchand
- Department of Paediatrics, Head, Heart Transplant, Labatt Family Heart Centre, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Steven A Webber
- Department of Pediatrics, Vanderbilt University School of Medicine, Pediatrician-in-Chief, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee, USA
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3
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Webber SA, Chin H, Wilkinson JD, Armstrong BD, Canter CE, Dipchand AI, Dodd DA, Feingold B, Lamour JM, Mahle WT, Singh TP, Zuckerman WA, Rossano JW, Morrison Y, Diop H, Demetris AJ, Bentlejewski C, Mohanakumar T, Odim J, Zeevi A. Impact of donor-specific anti-HLA antibody on cardiac hemodynamics and graft function 3 years after pediatric heart transplantation: First results from the CTOTC-09 multi-institutional study. Am J Transplant 2023; 23:1893-1907. [PMID: 37579817 PMCID: PMC10841212 DOI: 10.1016/j.ajt.2023.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 07/19/2023] [Accepted: 08/06/2023] [Indexed: 08/16/2023]
Abstract
The aim of this study (CTOTC-09) was to assess the impact of "preformed" (at transplant) donor-specific anti-HLA antibody (DSA) and first year newly detected DSA (ndDSA) on allograft function at 3 years after pediatric heart transplantation (PHTx). We enrolled children listed at 9 North American centers. The primary end point was pulmonary capillary wedge pressure (PCWP) at 3 years posttransplant. Of 407 enrolled subjects, 370 achieved PHTx (mean age, 7.7 years; 57% male). Pre-PHTx sensitization status was nonsensitized (n = 163, 44%), sensitized/no DSA (n = 115, 31%), sensitized/DSA (n = 87, 24%), and insufficient DSA data (n = 5, 1%); 131 (35%) subjects developed ndDSA. Subjects with any DSA had comparable PCWP at 3 years to those with no DSA. There were also no significant differences overall between the 2 groups for other invasive hemodynamic measurements, systolic graft function by echocardiography, and serum brain natriuretic peptide concentration. However, in the multivariable analysis, persistent first-year DSA was a risk factor for 3-year abnormal graft function. Graft and patient survival did not differ between groups. In summary, overall, DSA status was not associated with worse allograft function or inferior patient and graft survival at 3 years, but persistent first-year DSA was a risk factor for late graft dysfunction.
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Affiliation(s)
- Steven A Webber
- Department of Pediatrics, Vanderbilt University School of Medicine, Vanderbilt, Nashville, Tennessee, USA.
| | - Hyunsook Chin
- Rho Federal Systems Division, Durham, North Carolina, USA
| | - James D Wilkinson
- Department of Pediatrics, Vanderbilt University School of Medicine, Vanderbilt, Nashville, Tennessee, USA
| | | | - Charles E Canter
- Division of Pediatric Cardiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Anne I Dipchand
- Labatt Family Heart Center, Department of Paediatrics, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Debra A Dodd
- Department of Pediatrics, Vanderbilt University School of Medicine, Vanderbilt, Nashville, Tennessee, USA
| | - Brian Feingold
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jacqueline M Lamour
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Bronx, New York, USA
| | - William T Mahle
- Division of Pediatric Cardiology, Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Tajinder P Singh
- Department of Pediatric Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Warren A Zuckerman
- Division of Pediatric Cardiology, Columbia University Medical Center, New York, New York, USA
| | - Joseph W Rossano
- Division of Pediatric Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Yvonne Morrison
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Helena Diop
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Anthony J Demetris
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Carol Bentlejewski
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | | | - Jonah Odim
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Adriana Zeevi
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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4
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Goldberg JF, Truby LK, Agbor-Enoh S, Jackson AM, deFilippi CR, Khush KK, Shah P. Selection and Interpretation of Molecular Diagnostics in Heart Transplantation. Circulation 2023; 148:679-694. [PMID: 37603604 PMCID: PMC10449361 DOI: 10.1161/circulationaha.123.062847] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
The number of heart transplants performed annually in the United States and worldwide continues to increase, but there has been little change in graft longevity and patient survival over the past 2 decades. The reference standard for diagnosis of acute cellular and antibody-mediated rejection includes histologic and immunofluorescence evaluation of endomyocardial biopsy samples, despite invasiveness and high interrater variability for grading histologic rejection. Circulating biomarkers and molecular diagnostics have shown substantial predictive value in rejection monitoring, and emerging data support their use in diagnosing other posttransplant complications. The use of genomic (cell-free DNA), transcriptomic (mRNA and microRNA profiling), and proteomic (protein expression quantitation) methodologies in diagnosis of these posttransplant outcomes has been evaluated with varying levels of evidence. In parallel, growing knowledge about the genetically mediated immune response leading to rejection (immunogenetics) has enhanced understanding of antibody-mediated rejection, associated graft dysfunction, and death. Antibodies to donor human leukocyte antigens and the technology available to evaluate these antibodies continues to evolve. This review aims to provide an overview of biomarker and immunologic tests used to diagnose posttransplant complications. This includes a discussion of pediatric heart transplantation and the disparate rates of rejection and death experienced by Black patients receiving a heart transplant. This review describes diagnostic modalities that are available and used after transplant and the landscape of future investigations needed to enhance patient outcomes after heart transplantation.
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Affiliation(s)
- Jason F Goldberg
- Department of Heart Failure and Transplantation, Inova Heart and Vascular Institute, Falls Church, VA (J.F.G., C.R.d., P.S.)
- Department of Pediatrics, Inova L.J. Murphy Children's Hospital, Falls Church, VA (J.F.G.)
| | - Lauren K Truby
- Department of Medicine, University of Texas Southwestern, Dallas (L.K.T.)
| | - Sean Agbor-Enoh
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD (S.A.-E.)
- Applied Precision Genomics, National Heart, Lung and Blood Institute, Bethesda, MD (S.A.-E.)
| | - Annette M Jackson
- Department of Surgery, Duke University School of Medicine, Durham, NC (A.M.J.)
| | - Christopher R deFilippi
- Department of Heart Failure and Transplantation, Inova Heart and Vascular Institute, Falls Church, VA (J.F.G., C.R.d., P.S.)
| | - Kiran K Khush
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, CA (K.K.K.)
| | - Palak Shah
- Department of Heart Failure and Transplantation, Inova Heart and Vascular Institute, Falls Church, VA (J.F.G., C.R.d., P.S.)
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5
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Ellison M, Mangiola M, Marrari M, Bentlejewski C, Sadowski J, Zern D, Kramer CSM, Heidt S, Niemann M, Xu Q, Dipchand AI, Mahle WT, Rossano JW, Canter CE, Singh TP, Zuckerman WA, Hsu DT, Feingold B, Webber SA, Zeevi A. Immunologic risk stratification of pediatric heart transplant patients by combining HLA-EMMA and PIRCHE-II. Front Immunol 2023; 14:1110292. [PMID: 36999035 PMCID: PMC10043167 DOI: 10.3389/fimmu.2023.1110292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/28/2023] [Indexed: 03/16/2023] Open
Abstract
Human leukocyte antigen (HLA) molecular mismatch is a powerful biomarker of rejection. Few studies have explored its use in assessing rejection risk in heart transplant recipients. We tested the hypothesis that a combination of HLA Epitope Mismatch Algorithm (HLA-EMMA) and Predicted Indirectly Recognizable HLA Epitopes (PIRCHE-II) algorithms can improve risk stratification of pediatric heart transplant recipients. Class I and II HLA genotyping were performed by next-generation sequencing on 274 recipient/donor pairs enrolled in the Clinical Trials in Organ Transplantation in Children (CTOTC). Using high-resolution genotypes, we performed HLA molecular mismatch analysis with HLA-EMMA and PIRCHE-II, and correlated these findings with clinical outcomes. Patients without pre-formed donor specific antibody (DSA) (n=100) were used for correlations with post-transplant DSA and antibody mediated rejection (ABMR). Risk cut-offs were determined for DSA and ABMR using both algorithms. HLA-EMMA cut-offs alone predict the risk of DSA and ABMR; however, if used in combination with PIRCHE-II, the population could be further stratified into low-, intermediate-, and high-risk groups. The combination of HLA-EMMA and PIRCHE-II enables more granular immunological risk stratification. Intermediate-risk cases, like low-risk cases, are at a lower risk of DSA and ABMR. This new way of risk evaluation may facilitate individualized immunosuppression and surveillance.
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Affiliation(s)
- M. Ellison
- University of Pittsburgh Medical Center, Histocompatibility Laboratory, Pittsburgh, PA, United States
- *Correspondence: M. Ellison,
| | - M. Mangiola
- Transplant Institute, NYU Langone Health, New York University, New York, NY, United States
| | - M. Marrari
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - C. Bentlejewski
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - J. Sadowski
- University of Pittsburgh Medical Center, Histocompatibility Laboratory, Pittsburgh, PA, United States
| | - D. Zern
- University of Pittsburgh Medical Center, Histocompatibility Laboratory, Pittsburgh, PA, United States
| | | | - S. Heidt
- Department of Immunology, Leiden University Medical Center (LUMC), Leiden, Netherlands
| | - M. Niemann
- Research and Development, PIRCHE AG, Berlin, Germany
| | - Q. Xu
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - A. I. Dipchand
- Labatt Heart Centre, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - W. T. Mahle
- Children’s Healthcare of Atlanta, Emory University, Atlanta, GA, United States
| | - J. W. Rossano
- Division of Cardiology, Children’s Hospital of Philadelphia, Philadelphia, PA, United States
| | - C. E. Canter
- Division of Cardiology, Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, United States
| | - T. P. Singh
- Department of Cardiology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States
| | - W. A. Zuckerman
- Columbia University, Irving Medical Center, New York, NY, United States
| | - D. T. Hsu
- Division of Pediatric Cardiology, Children’s Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York, NY, United States
| | - B. Feingold
- Department of Pediatrics, Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States
| | - S. A. Webber
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, United States
| | - A. Zeevi
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
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6
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Bansal N, Raedi WA, Medar SS, Abraham L, Beddows K, Hsu DT, Lamour JM, Mahgerefteh J. Masked Hypertension in Pediatric Heart Transplant Recipients. Pediatr Cardiol 2023; 44:1003-1008. [PMID: 36656319 DOI: 10.1007/s00246-023-03096-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/10/2023] [Indexed: 01/20/2023]
Abstract
BACKGROUND Masked hypertension (HTN), especially, isolated nocturnal HTN (INH) has been shown to be a risk factor for cardiovascular disease (CVD) but is not studied well in pediatric heart transplant (PHT) patients. Ambulatory blood pressure monitoring (ABPM) is known to identify patients with HTN but is not used routinely in PHT. METHODS A single-center, prospective, cross-sectional study of PHT recipients was performed to observe the incidence of masked HTN using 24-h ABPM. The relationship between ABPM parameters and clinical variables was assessed using Spearman correlation coefficient. p value < 0.05 was considered significant. RESULTS ABPM was performed in 34 patients, mean age 14 ± 5 years, median 5.5 years post-PHT. All patients had normal cardiac function, left ventricular mass index and blood pressure measurements in the clinic. Four patients had known prior HTN and on medications, one of them was uncontrolled. Of the remaining 30 patients, 18 new patients were diagnosed with masked HTN, of which 14 had INH. Diurnal variation was abnormal in 82% (28/34) patients. 24-h diastolic blood pressure (DBP) index correlated with glomerular filtration rate (GFR) (r = - 0.44, p = 0.01). There was no correlation between other ABPM parameters with tacrolimus trough levels. CONCLUSIONS ABPM identified masked HTN in 60% of patients, with majority being INH. Abnormal circadian BP patterns were present in 82% and an association was found between GFR and DBP parameters. HTN, especially INH, is under-recognized in PHT recipients and ABPM has a role in their long-term care.
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Affiliation(s)
- Neha Bansal
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA.
| | - Waheed A Raedi
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
| | - Shivanand S Medar
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA.,Division of Pediatric Critical Care Medicine, Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Lincy Abraham
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
| | - Kimberly Beddows
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
| | - Daphne T Hsu
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
| | - Jacqueline M Lamour
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
| | - Joseph Mahgerefteh
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Ave- R1, Bronx, NY, 10467, USA
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Donovan DJ, Richmond ME, Bacha EA, Addonizio LJ, Zuckerman WA. Association between homograft tissue exposure and allosensitization prior to heart transplant in patients with congenital heart disease. Pediatr Transplant 2022; 26:e14201. [PMID: 34889487 DOI: 10.1111/petr.14201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/01/2021] [Accepted: 11/19/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Surgical repair for patients with congenital heart disease (CHD) often incorporates homograft tissue or other foreign material that can lead to allosensitization. We sought to identify the relationship between pre-sensitization prior to heart transplant and exposure to homograft tissue in CHD patients. METHODS Retrospective chart review of all CHD patients who underwent heart transplant at a major pediatric transplant center between 1/1/2011-3/31/18. Operative records determined use of homograft tissue or foreign material. Panel reactive antibody (PRA) and LuminexTM single-antigen bead (SAB) testing results were reviewed. Statistical analysis determined odds of pre-sensitization in patients exposed to homograft tissue. RESULTS Fifty-six CHD patients underwent transplant during the review period. Thirteen patients (23%) were pre-sensitized by PRA>10%. By SAB testing, 33 patients (59%) developed any anti-HLA antibody >0 MFI, 30 patients (54%) >2000 MFI, and 19 patients (34%) >6000 MFI. Patients with homografts were more likely to be pre-sensitized by PRA (OR = 7.31, p = .007), and to have developed any anti-HLA antibody at various levels, >0 (OR = 4.52, p = .034), >2000 (OR = 8.59, p = .003), and >6000 (OR = 8.50, p = .004). Of patients with homografts, those pre-sensitized by PRA had longer exposure times (9.80 vs 4.96 years, p = .025). There was no difference in exposure time with relation to pre-sensitization by SAB testing. CONCLUSIONS Previous exposure to homograft tissue appears to increase the odds of pre-sensitization by either the PRA or SAB testing. Longer exposure time to homograft tissue prior to transplant is associated with increased pre-sensitization at transplant as determined by PRA, though not by SAB testing.
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Affiliation(s)
- Denis J Donovan
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Irving Medical Center, New York, New York, USA
| | - Marc E Richmond
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Irving Medical Center, New York, New York, USA
| | - Emile A Bacha
- Division of Pediatric Cardiac Surgery, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Irving Medical Center, New York, New York, USA
| | - Linda J Addonizio
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Irving Medical Center, New York, New York, USA
| | - Warren A Zuckerman
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Irving Medical Center, New York, New York, USA
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8
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Mangiola M, Ellison M, Marrari M, Bentlejewski C, Sadowski J, Zern D, Niemann M, Feingold B, Webber S, Zeevi A, Dipchand AI, Lamour JM, Mahle WT, Rossano JW, Scheel JN, Singh TP, Zuckerman WA. Immunologic Risk Stratification of Pediatric Heart Transplant Patients by Combining Hlamatchmaker and PIRCHE-II. J Heart Lung Transplant 2022; 41:952-960. [DOI: 10.1016/j.healun.2022.03.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 10/18/2022] Open
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9
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Kerstein JS, Donovan DJ, Zinn MD, Richmond ME, Cheung EW, Addonizio LJ, Zuckerman WA. Anti-hypertensive treatment in the immediate post-operative period and 1 year after pediatric heart transplantation. Pediatr Transplant 2020; 24:e13801. [PMID: 32820859 DOI: 10.1111/petr.13801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/07/2020] [Accepted: 06/28/2020] [Indexed: 11/29/2022]
Abstract
Hypertension is a known complication of pediatric heart transplantation. We sought to identify factors associated with anti-hypertensive use in pediatric heart transplant recipients immediately post-transplant and oral anti-hypertensive use at discharge and 1-year post-transplant. Retrospective chart review was conducted of patients ≤18 years who underwent heart transplantation at two major heart transplant centers between August 1, 2009 and December 31, 2017 with ≥1-year follow-up. Exclusion criteria included re-transplant, multi-organ recipients, survival <1 year, and comorbidities associated with hypertension. Anti-hypertensive use was recorded during initial ICU stay, at discharge, and 1-year post-transplant. Univariate and multivariate analyses determined associations of demographic and diagnostic factors and need for anti-hypertensives. There were 188 patients that met inclusion criteria. Anti-hypertensive infusions were required in the ICU post-transplant in 46 patients (24.5%) for a median of 3 days (1-21 days). Oral anti-hypertensives were required in 58 patients (30.9%) at discharge and 1-year post-transplant. Anti-hypertensive infusion in the ICU post-transplant was associated with donor-to-recipient weight ratio. Oral anti-hypertensive use at discharge was associated with weight ratio and pretransplant VAD use, and at 1-year, post-transplant was associated with age at transplant, steroid use at discharge, and oral anti-hypertensive use at discharge. Hypertension is common immediately following and 1-year post-transplant. Weight ratio was the only independent predictor of anti-hypertensive use in the early post-transplant period, whereas VAD use was also associated with anti-hypertensive use at discharge. Anti-hypertensive use 1-year post-transplant was not associated with those factors, but rather with age at transplant and steroid use.
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Affiliation(s)
- Jason S Kerstein
- Department of Pediatrics, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Denis J Donovan
- Department of Pediatrics, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA
| | - Matthew D Zinn
- Division of Pediatric Cardiology, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Marc E Richmond
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA
| | - Eva W Cheung
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA
| | - Linda J Addonizio
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA
| | - Warren A Zuckerman
- Division of Pediatric Cardiology, New York-Presbyterian Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, NY, USA
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10
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Mahle WT, Mason KL, Dipchand AI, Richmond M, Feingold B, Canter CE, Hsu DT, Singh TP, Shaddy RE, Armstrong BD, Zeevi A, Iklé DN, Diop H, Odim J, Webber SA. Hospital readmission following pediatric heart transplantation. Pediatr Transplant 2019; 23:e13561. [PMID: 31483086 PMCID: PMC8455069 DOI: 10.1111/petr.13561] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/26/2019] [Accepted: 07/01/2019] [Indexed: 11/29/2022]
Abstract
The frequency, indications, and outcomes for readmission following pediatric heart transplantation are poorly characterized. A better understanding of this phenomenon will help guide strategies to address the causes of readmission. Data from the Clinical Trials in Organ Transplantation for Children (CTOTC-04) multi-institutional collaborative study were utilized to determine incidence of, and risk factors for, hospital readmission within 30 days and 1 year from initial hospital discharge. Among 240 transplants at 8 centers, 227 subjects were discharged and had follow-up. 129 subjects (56.8%) were readmitted within one year; 71 had two or more readmissions. The 30-day and 1-year freedom from readmission were 70.5% (CI: 64.1%, 76.0%) and 42.2% (CI: 35.7%, 48.7%), respectively. The most common indications for readmissions were infection followed by rejection and fever without confirmed infection, accounting for 25.0%, 10.6%, and 6.2% of readmissions, respectively. Factors independently associated with increased risk of first readmission within 1 year (Cox proportional hazard model) were as follows: transplant in infancy (P = .05), longer transplant hospitalization (P = .04), lower UNOS urgency status (2/IB vs 1A) at transplant (P = .04), and Hispanic ethnicity (P = .05). Hospital readmission occurs frequently in the first year following discharge after heart transplantation with highest risk in the first 30 days. Infection is more common than rejection as cause for readmission, with death during readmission being rare. A number of patient factors are associated with higher risk of readmission. A fuller understanding of these risk factors may help tailor strategies to reduce unnecessary hospital readmission.
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Affiliation(s)
- William T. Mahle
- Division of Pediatric Cardiology, Children’s Healthcare of Atlanta, Atlanta, Georgia
| | | | - Anne I. Dipchand
- Labatt Family Heart Center, Department of Paediatrics, Hospital for Sick Children, Toronto, ON, Canada
| | - Marc Richmond
- Department of Pediatrics, New York-Presbyterian Morgan Stanley Children’s Hospital, New York, New York
| | - Brian Feingold
- Department of Pediatrics and Clinical and Translational Science, University of Pittsburgh School of Medicine, Pittsburgh, PA (Feingold)
| | - Charles E. Canter
- Division of Pediatric Cardiology, Washington University School of Medicine, St. Louis, Missouri
| | - Daphne T. Hsu
- Division of Pediatric Cardiology, Children’s Hospital at Montefiore, Bronx, New York
| | - Tajinder P. Singh
- Department of Cardiology, Boston Children’s Hospital, Boston, Massachusetts
| | - Robert E. Shaddy
- Division of Pediatric Cardiology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | | | - Adriana Zeevi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - David N. Iklé
- Rho Federal Systems Division, Chapel Hill, North Carolina
| | - Helena Diop
- Transplantation Branch, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Jonah Odim
- Transplantation Branch, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Steven A. Webber
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
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11
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Godown J, Gaies M, Wilkinson JD. Leveraging big data to advance knowledge in pediatric heart failure and heart transplantation. Transl Pediatr 2019; 8:342-348. [PMID: 31728327 PMCID: PMC6825960 DOI: 10.21037/tp.2019.07.09] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 07/11/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Justin Godown
- Division of Pediatric Cardiology, Monroe Carell Jr. Children’s Hospital, Nashville, TN, USA
| | - Michael Gaies
- Division of Cardiology, Department of Pediatrics, C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor, MI, USA
| | - James D. Wilkinson
- Department of Pediatrics, Monroe Carell Jr. Children’s Hospital, Nashville, TN, USA
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12
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Abstract
Despite advancements in transplant immunosuppression and techniques for managing critically ill patients awaiting heart transplantation, children who are immunologically sensitized to human leukocyte antigen remain at increased risk for morbidity and mortality, both while awaiting and after heart transplant. In this review we will discuss the epidemiology of sensitization, review the immunologic basis and methods of human leukocyte antigen antibody detection, describe outcomes for sensitized pediatric transplant candidates, and consider both pre- and post-transplant management options for sensitized patients.
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Affiliation(s)
- Erik L Frandsen
- Division of Pediatric Cardiology, Seattle Children's Hospital, Seattle, Washington, USA
| | - Erin L Albers
- Division of Pediatric Cardiology, Seattle Children's Hospital, Seattle, Washington, USA
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13
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Lamour JM, Mason KL, Hsu DT, Feingold B, Blume ED, Canter CE, Dipchand AI, Shaddy RE, Mahle WT, Zuckerman WA, Bentlejewski C, Armstrong BD, Morrison Y, Diop H, Iklé DN, Odim J, Zeevi A, Webber SA. Early outcomes for low-risk pediatric heart transplant recipients and steroid avoidance: A multicenter cohort study (Clinical Trials in Organ Transplantation in Children - CTOTC-04). J Heart Lung Transplant 2019; 38:972-981. [PMID: 31324444 PMCID: PMC8359669 DOI: 10.1016/j.healun.2019.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/12/2019] [Accepted: 06/16/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Immunosuppression strategies have changed over time in pediatric heart transplantation. Thus, comorbidity profiles may have evolved. Clinical Trials in Organ Transplantation in Children-04 is a multicenter, prospective, cohort study assessing the impact of pre-transplant sensitization on outcomes after pediatric heart transplantation. This sub-study reports 1-year outcomes among recipients without pre-transplant donor-specific antibodies (DSAs). METHODS We recruited consecutive candidates (<21 years) at 8 centers. Sensitization status was determined by a core laboratory. Immunosuppression was standardized as follows: Thymoglobulin induction with tacrolimus and/or mycophenolate mofetil maintenance. Steroids were not used beyond 1 week. Rejection surveillance was by serial biopsy. RESULTS There were 240 transplants. Subjects for this sub-study (n = 186) were non-sensitized (n = 108) or had no DSAs (n = 78). Median age was 6 years, 48.4% were male, and 38.2% had congenital heart disease. Patient survival was 94.5% (95% confidence interval, 90.1-97.0%). Freedom from any type of rejection was 67.5%. Risk factors for rejection were older age at transplant and presence of non-DSAs pre-transplant. Freedom from infection requiring hospitalization/intravenous anti-microbials was 75.4%. Freedom from rehospitalization was 40.3%. New-onset diabetes mellitus and post-transplant lymphoproliferative disorder (PTLD) occurred in 1.6% and 1.1% of subjects, respectively. There was no decline in renal function over the first year. Corticosteroids were used in 14.5% at 1 year. CONCLUSIONS Pediatric heart transplantation recipients without DSAs at transplant and managed with a steroid avoidance regimen have excellent short-term survival and a low risk of first-year diabetes mellitus and PTLD. Rehospitalization remains common. These contemporary observations allow for improved caregiver and/or patient counseling and provide the necessary outcomes data to help design future randomized controlled trials.
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Affiliation(s)
- Jacqueline M Lamour
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Bronx, New York, New York.
| | | | - Daphne T Hsu
- Division of Pediatric Cardiology, Children's Hospital at Montefiore, Bronx, New York, New York
| | - Brian Feingold
- Departments of Pediatrics and Clinical and Translational Science, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Elizabeth D Blume
- Department of Pediatric Cardiology, Boston Children's Hospital, Boston, Massachusetts
| | - Charles E Canter
- Division of Pediatric Cardiology, Washington University School of Medicine, St. Louis, Missouri
| | - Anne I Dipchand
- Department of Paediatrics, Labatt Family Heart Center, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Robert E Shaddy
- Division of Pediatric Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - William T Mahle
- Division of Pediatric Cardiology, Children's Healthcare of Atlanta, Atlanta, Georgia
| | - Warren A Zuckerman
- Division of Pediatric Cardiology, Columbia University Medical Center, New York, New York
| | - Carol Bentlejewski
- Division of Pediatric Cardiology, Columbia University Medical Center, New York, New York
| | | | | | - Helena Diop
- Rho Federal Systems Division, Chapel Hill, North Carolina
| | - David N Iklé
- Rho Federal Systems Division, Chapel Hill, North Carolina
| | - Jonah Odim
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Adriana Zeevi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Steven A Webber
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
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14
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Sharma M, Webber SA, Zeevi A, Mohanakumar T. Molecular events contributing to successful pediatric cardiac transplantation in HLA sensitized recipients. Hum Immunol 2019; 80:248-256. [PMID: 30710563 DOI: 10.1016/j.humimm.2019.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 01/29/2019] [Accepted: 01/29/2019] [Indexed: 10/27/2022]
Abstract
Antibodies to HLA resulting in positive cytotoxicity crossmatch are generally considered a contraindication for cardiac transplantation. However, cardiac transplantations have been performed in children by reducing the Abs and modifying immunosuppression. To identify mechanisms leading to allograft acceptance in the presence of Abs to donor HLA, we analyzed priming events in endothelial cells (EC) by incubating with sera containing low levels of anti-HLA followed by saturating concentration of anti-HLA. Pre-transplant sera were obtained from children with low levels of Abs to HLA who underwent transplantation. EC were selected for donor HLA and exposed to sera for 72 h (priming), followed by saturating concentrations of anti-HLA (challenge). Priming of EC with sera induced the phosphatidylinositol 3-kinase/Akt mediated by the BMP4/WNT pathway and subsequent challenge with panel reactive antibody sera increased survival genes Bcl2 and Heme oxygenase-1, decreased adhesion molecules, induced complement inhibitory proteins and reduced pro-inflammatory cytokines. In contrast, EC which did not express donor HLA showed decreased anti-apoptotic genes. Primed EC, upon challenge with anti-HLA, results in increased survival genes, decreased adhesion molecules, induction of complement inhibitory proteins, and downregulation of pro-inflammatory cytokines which may result in accommodation of pediatric cardiac allografts despite HLA sensitization.
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Affiliation(s)
- Monal Sharma
- Norton Thoracic Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
| | - S A Webber
- Vanderbilt University School of Medicine, Nashville, TN, United States
| | - A Zeevi
- University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - T Mohanakumar
- Norton Thoracic Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States.
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15
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Valenzuela NM, Askar M, Heidt S, Jindra P, Madbouly A, Pinelli D, Jackson A, Hidalgo LG. Minimal data reporting standards for serological testing for histocompatibility. Hum Immunol 2018; 79:865-868. [DOI: 10.1016/j.humimm.2018.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 08/15/2018] [Indexed: 12/30/2022]
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16
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Dipchand AI, Webber S, Mason K, Feingold B, Bentlejewski C, Mahle WT, Shaddy R, Canter C, Blume ED, Lamour J, Zuckerman W, Diop H, Morrison Y, Armstrong B, Ikle D, Odim J, Zeevi A. Incidence, characterization, and impact of newly detected donor-specific anti-HLA antibody in the first year after pediatric heart transplantation: A report from the CTOTC-04 study. Am J Transplant 2018; 18:2163-2174. [PMID: 29442424 PMCID: PMC6092243 DOI: 10.1111/ajt.14691] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 01/30/2018] [Accepted: 02/04/2018] [Indexed: 01/25/2023]
Abstract
Data on the clinical importance of newly detected donor-specific anti-HLA antibodies (ndDSAs) after pediatric heart transplantation are lacking despite mounting evidence of the detrimental effect of de novo DSAs in solid organ transplantation. We prospectively tested 237 pediatric heart transplant recipients for ndDSAs in the first year posttransplantation to determine their incidence, pattern, and clinical impact. One-third of patients developed ndDSAs; when present, these were mostly detected within the first 6 weeks after transplantation, suggesting that memory responses may predominate over true de novo DSA production in this population. In the absence of preexisting DSAs, patients with ndDSAs had significantly more acute cellular rejection but not antibody-mediated rejection, and there was no impact on graft and patient survival in the first year posttransplantation. Risk factors for ndDSAs included common sensitizing events. Given the early detection of the antibody response, memory responses may be more important in the first year after pediatric heart transplantation and patients with a history of a sensitizing event may be at risk even with a negative pretransplantation antibody screen. The impact on late graft and patient outcomes of first-year ndDSAs is being assessed in an extended cohort of patients.
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Affiliation(s)
- A. I. Dipchand
- Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - S. Webber
- Vanderbilt University Medical Center, Nashville, TN
| | | | - B. Feingold
- Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA
| | | | - W. T. Mahle
- Children’s Healthcare of Atlanta, Atlanta, GA
| | - R. Shaddy
- Children’s Hospital of Philadelphia, Philadelphia, PA
| | - C. Canter
- St Louis Children’s Hospital, St Louis, MO
| | | | - J. Lamour
- Montefiore Children’s Hospital, New York, NY
| | | | - H. Diop
- National Institutes of Health, Bethesda, MD
| | | | | | | | - J. Odim
- National Institutes of Health, Bethesda, MD
| | - A. Zeevi
- Department of Pathology, UPMC, Pittsburgh, PA
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17
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Webber S, Zeevi A, Mason K, Addonizio L, Blume E, Dipchand A, Shaddy R, Feingold B, Canter C, Hsu D, Mahle W, Armstrong B, Morrison Y, Ikle D, Diop H, Odim J. Pediatric heart transplantation across a positive crossmatch: First year results from the CTOTC-04 multi-institutional study. Am J Transplant 2018; 18:2148-2162. [PMID: 29673058 DOI: 10.1111/ajt.14876] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 04/01/2018] [Accepted: 04/03/2018] [Indexed: 01/25/2023]
Abstract
Sensitization is common in pediatric heart transplant candidates and waitlist mortality is high. Transplantation across a positive crossmatch may reduce wait time, but is considered high risk. We prospectively recruited consecutive candidates at eight North American centers. At transplantation, subjects were categorized as nonsensitized or sensitized (presence of ≥1 HLA antibody with MFI ≥1000 using single antigen beads). Sensitized subjects were further classified as complement-dependent cytotoxicity crossmatch (CDC-crossmatch) positive or negative and as donor-specific antibodies (DSA) positive or negative. Immunosuppression was standardized. CDC-crossmatch-positive subjects also received perioperative antibody removal, maintenance corticosteroids, and intravenous immunoglobulin. The primary endpoint was the 1 year incidence rate of a composite of death, retransplantation, or rejection with hemodynamic compromise. 317 subjects were screened, 290 enrolled and 240 transplanted (51 with pretransplant DSA, 11 with positive CDC-crossmatch). The incidence rates of the primary endpoint did not differ statistically between groups; nonsensitized 6.7% (CI: 2.7%, 13.3%), sensitized crossmatch positive 18.2% (CI: 2.3%, 51.8%), sensitized crossmatch negative 10.7% (CI: 5.7%, 18.0%), P = .2354. The primary endpoint also did not differ by DSA status. Freedom from antibody-mediated and cellular rejection was lower in the crossmatch positive group and/or in the presence of DSA. Follow-up will determine if acceptable outcomes can be achieved long-term.
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Affiliation(s)
- S Webber
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - A Zeevi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - K Mason
- Rho Federal Systems Division, Chapel Hill, NC, USA
| | - L Addonizio
- Division of Pediatric Cardiology, Columbia University Medical Center, New York, NY, USA
| | - E Blume
- Department of Pediatric Cardiology, Boston Children's Hospital, Boston, MA, USA
| | - A Dipchand
- Department of Paediatrics, Hospital for Sick Children, Labatt Family Heart Center, Toronto, Ontario, Canada
| | - R Shaddy
- Division of Pediatric Cardiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - B Feingold
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - C Canter
- Division of Pediatric Cardiology, Washington University School of Medicine, St. Louis, MO, USA
| | - D Hsu
- Division of Pediatric Cardiology, Albert Einstein College of Medicine/Children's Hospital at Montefiore, Bronx, NY, USA
| | - W Mahle
- Division of Pediatric Cardiology, Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - B Armstrong
- Rho Federal Systems Division, Chapel Hill, NC, USA
| | - Y Morrison
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - D Ikle
- Rho Federal Systems Division, Chapel Hill, NC, USA
| | - H Diop
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - J Odim
- Transplantation Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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