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1.
Am J Transplant ; 17(6): 1515-1524, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28251816

ABSTRACT

Low case volume has been associated with poor outcomes in a wide spectrum of procedures. Our objective was to study the association of low case volume and worse outcomes in pediatric heart transplant centers, taking the novel approach of including waitlist outcomes in the analysis. We studied a cohort of 6482 candidates listed in the Organ Procurement and Transplantation Network for pediatric heart transplantation between 2002 and 2014; 4665 (72%) of the candidates underwent transplantation. Candidates were divided into groups according to the average annual transplantation volume of the listing center during the study period: more than 10, six to 10, three to five, or fewer than three transplantations. We used multivariate Cox regression analysis to identify independent risk factors for waitlist and posttransplantation mortality. Of the 6482 candidates, 24% were listed in low-volume centers (fewer than three annual transplantations). Of these listed candidates in low-volume centers, only 36% received a transplant versus 89% in high-volume centers (more than 10 annual transplantations) (p < 0.001). Listing at a low-volume center was the most significant risk factor for waitlist death (hazard ratio [HR] 4.5, 95% confidence interval [CI] 3.5-5.7 in multivariate Cox regression and HR 5.6, CI 4.4-7.3 in multivariate competing risk regression) and was significant for posttransplantation death (HR 1.27, 95% CI 1.0-1.6 in multivariate Cox regression). During the study period, one-fourth of pediatric transplant candidates were listed in low-volume transplant centers. These children had a limited transplantation rate and a much greater risk of dying while on the waitlist.


Subject(s)
Graft Rejection/mortality , Heart Transplantation/mortality , Hospitals, Low-Volume/statistics & numerical data , Postoperative Complications , Tissue and Organ Procurement , Waiting Lists , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Graft Survival , Humans , Infant , Infant, Newborn , Male , Prognosis , Retrospective Studies , Risk Factors
2.
Am J Transplant ; 15(7): 1855-63, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25689873

ABSTRACT

A prognostic index to predict survival after liver transplantation could address several clinical needs. Here, we devised a scoring system that predicts recipient survival after pediatric liver transplantation. We used univariate and multivariate analysis on 4565 pediatric liver transplant recipients data and identified independent recipient and donor risk factors for posttransplant mortality at 3 months. Multiple imputation was used to account for missing variables. We identified five factors as significant predictors of recipient mortality after pediatric liver transplantation: two previous transplants (OR 5.88, CI 2.88-12.01), one previous transplant (OR 2.54, CI 1.75-3.68), life support (OR 3.68, CI 2.39-5.67), renal insufficiency (OR 2.66, CI 1.84-3.84), recipient weight under 6 kilograms (OR 1.67, CI 1.12-2.36) and cadaveric technical variant allograft (OR 1.38, CI 1.03-1.83). The Survival Outcomes Following Pediatric Liver Transplant score assigns weighted risk points to each of these factors in a scoring system to predict 3-month recipient survival after liver transplantation with a C-statistic of 0.74. Although quite accurate when compared with other posttransplant survival models, we would not advocate individual clinical application of the index.


Subject(s)
Endpoint Determination/methods , Liver Diseases/mortality , Liver Transplantation/mortality , Models, Theoretical , Outcome Assessment, Health Care , Adolescent , Child , Child, Preschool , Decision Support Techniques , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Liver Diseases/diagnosis , Liver Diseases/surgery , Male , Multivariate Analysis , Postoperative Complications , Prognosis , Retrospective Studies , Risk Factors , Survival Rate
3.
Oncogene ; 34(33): 4368-78, 2015 Aug 13.
Article in English | MEDLINE | ID: mdl-25362854

ABSTRACT

MCPH1, also known as BRIT1, has recently been identified as a novel key regulatory gene of the DNA damage response pathway. MCPH1 is located on human chromosome 8p23.1, where human cancers frequently show loss of heterozygosity. As such, MCPH1 is aberrantly expressed in many malignancies, including breast and ovarian cancers, and the function of MCPH1 has been implicated in tumor suppression. However, it remains poorly understood whether MCPH1 deficiency leads to tumorigenesis. Here we generated and studied both Mcph1(-/-) and Mcph1(-/-)p53(-/-) mice; we showed that Mcph1(-/-) mice developed tumors with long latency, and that primary lymphoma developed significantly earlier in Mcph1(-/-)p53(-/-) mice than in Mcph11(+/+)p53(-/-) and Mcph1(+/-)p53(-/-) mice. The Mcph1(-/-)p53(-/-) lymphomas and derived murine embryonic fibroblasts (MEFs) were both more sensitive to irradiation. Mcph1 deficiency resulted in remarkably increased chromosome and chromatid breaks in Mcph1(-/-)p53(-/-) lymphomas and MEFs, as determined by metaphase spread assay and spectral karyotyping analysis. In addition, Mcph1 deficiency significantly enhanced aneuploidy as well as abnormal centrosome multiplication in Mcph1(-/-)p53(-/-) cells. Meanwhile, Mcph1 deficiency impaired double strand break (DSB) repair in Mcph1(-/-)p53(-/-) MEFs as demonstrated by neutral Comet assay. Compared with Mcph1(+/+)p53(-/-) MEFs, homologous recombination and non-homologous end-joining activities were significantly decreased in Mcph1(-/-)p53(-/-) MEFs. Notably, reconstituted MCPH1 rescued the defects of DSB repair and alleviated chromosomal aberrations in Mcph1(-/-)p53(-/-) MEFs. Taken together, our data demonstrate MCPH1 deficiency promotes genomic instability and increases cancer susceptibility. Our study using knockout mouse models provides convincing genetic evidence that MCPH1 is a bona fide tumor suppressor gene. Its deficiency leading to defective DNA repair in tumors can be used to develop novel targeted cancer therapies in the future.


Subject(s)
Cell Transformation, Neoplastic/genetics , Chromosomal Proteins, Non-Histone/deficiency , Genomic Instability/genetics , Lymphoma/genetics , Lymphoma/pathology , Aneuploidy , Animals , Cell Cycle Proteins , Cell Transformation, Neoplastic/pathology , Centrosome/metabolism , Chromosomal Proteins, Non-Histone/genetics , Chromosome Aberrations , Cytoskeletal Proteins , DNA Breaks, Double-Stranded , DNA Repair/genetics , Disease Models, Animal , Fibroblasts/metabolism , Genes, Tumor Suppressor/physiology , Homologous Recombination/genetics , Lymphoma/metabolism , Mice , Mice, Knockout , Tumor Suppressor Protein p53
4.
Am J Transplant ; 12(11): 3021-30, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22947426

ABSTRACT

Maribavir is an oral benzimidazole riboside with potent in vitro activity against cytomegalovirus (CMV), including some CMV strains resistant to ganciclovir. In a randomized, double-blind, multicenter trial, the efficacy and safety of prophylactic oral maribavir (100 mg twice daily) for prevention of CMV disease were compared with oral ganciclovir (1000 mg three times daily) in 303 CMV-seronegative liver transplant recipients with CMV-seropositive donors (147 maribavir; 156 ganciclovir). Patients received study drug for up to 14 weeks and were monitored for CMV infection by blood surveillance tests and also for the development of CMV disease. The primary endpoint was Endpoint Committee (EC)-confirmed CMV disease within 6 months of transplantation. In a modified intent-to-treat analysis, the noninferiority of maribavir compared to oral ganciclovir for prevention of CMV disease was not established (12% with maribavir vs. 8% with ganciclovir: event rate difference of 0.041; 95% CI: -0.038, 0.119). Furthermore, significantly fewer ganciclovir patients had EC-confirmed CMV disease or CMV infection by pp65 antigenemia or CMV DNA PCR compared to maribavir patients at both 100 days (20% vs. 60%; p < 0.0001) and at 6 months (53% vs. 72%; p = 0.0053) after transplantation. Graft rejection, patient survival, and non-CMV infections were similar for maribavir and ganciclovir patients. Maribavir was well-tolerated and associated with fewer hematological adverse events than oral ganciclovir. At a dose of 100 mg twice daily, maribavir is safe but not adequate for prevention of CMV disease in liver transplant recipients at high risk for CMV disease.


Subject(s)
Antiviral Agents/administration & dosage , Benzimidazoles/administration & dosage , Cytomegalovirus Infections/drug therapy , Graft Rejection/prevention & control , Liver Transplantation/methods , Ribonucleosides/administration & dosage , Acyclovir/administration & dosage , Administration, Oral , Cytomegalovirus Infections/diagnosis , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Follow-Up Studies , Ganciclovir/administration & dosage , Graft Rejection/virology , Graft Survival , Humans , Liver Transplantation/adverse effects , Liver Transplantation/immunology , Male , Postoperative Complications/drug therapy , Postoperative Complications/virology , Prospective Studies , Risk Assessment , Treatment Outcome
5.
Ir J Med Sci ; 179(4): 605-6, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20734157

ABSTRACT

INTRODUCTION: The liver and biliary tree are common sites of initial metastasis for many primary tumors. However, we recently encountered a patient who presented with biliary-tree tumor encasement as a first metastasis from squamous carcinoma of the anus. METHODS: To our knowledge, this has not been previously described in the literature. CONCLUSIONS: As obstructive jaundice is a relatively common presenting sign in the emergency room and in general surgical clinics, we thus recommend early consideration of metastatic disease as a differential diagnosis in patients post-chemoradiotherapy for anal carcinoma who present with obstructive jaundice.


Subject(s)
Anus Neoplasms/pathology , Biliary Tract Neoplasms/secondary , Carcinoma, Squamous Cell/secondary , Anus Neoplasms/surgery , Bile Ducts/pathology , Biliary Tract Neoplasms/surgery , Carcinoma, Squamous Cell/surgery , Common Bile Duct Neoplasms , Dilatation, Pathologic , Epithelium/pathology , Female , Humans , Jaundice, Obstructive/etiology , Jejunostomy , Middle Aged , Pancreatic Ducts/pathology
6.
Am J Transplant ; 7(5): 1265-70, 2007 May.
Article in English | MEDLINE | ID: mdl-17359503

ABSTRACT

Extended criteria donor (ECD) liver allografts are often allocated to less severely ill liver transplant (LT) candidates who are at a relatively lower risk of pretransplant mortality, but it is not clear that the use of ECD allografts will decrease center waitlist mortality (WLM). Individual patient data from the UNOS OPTN database (2002-2005) were aggregated to obtain center-specific data. Deceased donor allografts with any of the following characteristics were defined as ECDs: from a donor with any of the criteria described by the New York State Department of Health Workgroup; or 12+ h of cold ischemia. Multivariate regression was used to examine the relationship between WLM and ECD, non-ECD and LDLT use after adjusting for candidate severity of illness. A total of 3555 ECD transplants, 11,660 standard criteria donor (SCD) transplants, and 717 LDLTs were performed at 100 centers during this period. The model demonstrated that SCD and ECD LTs were inversely correlated with a center's WLM (beta=-0.242 and -0.221, respectively; p

Subject(s)
Liver Diseases/mortality , Liver Transplantation/statistics & numerical data , Patient Selection , Tissue Donors/classification , Tissue and Organ Procurement/methods , Waiting Lists , Adult , Eligibility Determination , Humans , Liver Diseases/surgery , Middle Aged , Models, Theoretical , Multivariate Analysis , Risk Factors , Severity of Illness Index , Survival Analysis , Tissue and Organ Procurement/statistics & numerical data , Transplantation, Homologous , United States
7.
Am J Transplant ; 7(4): 1010-20, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17391141

ABSTRACT

The use of regional human islet cell processing centers (ICPC) supporting distant clinical islet transplantation programs (CITP) has proven successful in recent clinical trials. Standardization of islet shipping protocols is needed to preserve cell product identity, quantity, quality and sterility, and to meet criteria for transplantation. We evaluated the use of gas-permeable bags for human islet preparation shipment from a single ICPC to two remote CITPs. Product release tests (counts, purity, viability, sterility and potency) were performed at both centers using identical protocols to determine adequacy for transplantation.Thirty-five islet preparations were shipped either immediately after isolation (n = 20) or following culture (n = 15). Islet recovery rate after shipment was higher in cultured preparations, when compared to those not cultured (91.2 +/- 4.9% vs. 72.9 +/- 4.7%, respectively; p < 0.05), though the overall recovery rate based on isolation and pre-transplant counts was comparable (72.9 +/- 4.7% vs. 70.4 +/- 3.5%, respectively; p = N.S.). All preparations met product release criteria for transplantation. Additional experiments showed that gas-permeable bags led to improved recovery and potency, when compared to 50-mL conical tubes or to non-gas-permeable bags for shipment.Collectively, our data demonstrate that the use of gas-permeable bags is efficient for clinical-grade and should be preferred also for the shipment of research-grade islet preparations.


Subject(s)
Islets of Langerhans/cytology , Organ Transplantation , Tissue and Organ Harvesting/methods , Tissue and Organ Procurement/methods , Tissue and Organ Procurement/organization & administration , Cell Culture Techniques/methods , Cell Survival , Humans , Time Factors
8.
Am J Transplant ; 6(9): 2060-8, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16827790

ABSTRACT

We investigated the effects of nicotinamide (NA) supplementation of the processing medium during islet isolation. One hundred and two human pancreata were processed for clinical transplantation after preservation either in the University of Wisconsin (UW) or using the two-layer method (TLM). Pancreata were then divided into four groups and retrospectively analyzed. Group I: UW preservation followed by processing without NA, Group II: UW preservation and processing with NA, Group III: TLM preservation without NA, Group IV: TLM preservation with NA. We observed a significant increase in islet yield in Group II (4343+/-348 IEQ/g) [mean+/-SEM], compared to Group I (2789+/-348 IEQ/g) (p=0.005). Similarly, a significant increase in islet yield was observed when NA was used in the processing of organs preserved with TLM (Group IV: 5538+/-413 vs. Group III: 3500+/-629; p=0.02). Furthermore islet yield was higher in Group IV than in Group II (p<0.05). The percentages of preparations that qualified for transplantation were 25, 47, 45, 69% in Groups I, II, III, IV, respectively. Addition of NA to the processing medium significantly improved islet yields in both the UW and TLM preservation protocols, allowing for a higher percentage of islet preparations to qualify for clinical transplantation.


Subject(s)
Cell Separation/methods , Islets of Langerhans/cytology , Niacinamide/pharmacology , Pancreas/drug effects , Adenosine , Adult , Allopurinol , Diabetes Mellitus, Type 1/surgery , Glutathione , Humans , Insulin , Islets of Langerhans Transplantation , Middle Aged , Organ Preservation , Organ Preservation Solutions , Raffinose , Retrospective Studies
9.
Transpl Infect Dis ; 8(2): 108-12, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16734634

ABSTRACT

BACKGROUND: Polymorphisms of the solute carrier family 11 member 1 (Slc11a1) gene have previously been associated with susceptibility to infectious disease, anti-tumor defenses, and autoimmune diseases. We postulated that polymorphisms of the gene may also be associated with susceptibility to post-transplant lymphoproliferative disease (PTLD), a disease thought to be related to an impaired immune response to Epstein-Barr virus (EBV) in immunosuppressed patients. METHODS: Whole blood samples were obtained from 45 pediatric patients who underwent liver transplantation. Polymerase chain reaction (PCR) was used to amplify a 3' region of the gene that includes an exon 15 single-nucleotide substitution (referred to as D543N) and a 4-bp deletion polymorphism (referred to as 3'-UTR). PCR products were digested using AvaII and FokI restriction enzymes for the D543N and 3'-UTR polymorphisms, respectively. PTLD disease status and EBV virus serum titers of all patients were obtained from hospital records. RESULTS: Six of the 45 pediatric transplant recipients developed PTLD. An association was found between 3'-UTR polymorphisms of Slc11a1 and incidence of PTLD after liver transplantation (P = 0.005). In addition, post-transplant serum EBV titers were higher (P = 0.009) for recipients with certain Slc11a1 polymorphisms. No association was found between the D543N polymorphism and incidence of PTLD. CONCLUSION: 3'-UTR polymorphisms of the Slc11a1 gene appear to be associated with susceptibility to PTLD and the immune response to EBV in pediatric liver transplant recipients. Genotyping of pediatric patients undergoing liver transplantation may enable early identification of patients at high risk for developing high EBV titers and/or PTLD.


Subject(s)
Cation Transport Proteins/genetics , Liver Transplantation/physiology , Lymphoproliferative Disorders/genetics , 3' Untranslated Regions/genetics , Adolescent , Cation Transport Proteins/immunology , Child , Child, Preschool , Epstein-Barr Virus Infections/blood , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/immunology , Female , Genetic Predisposition to Disease , Humans , Immunity, Cellular/immunology , Infant , Liver Transplantation/adverse effects , Liver Transplantation/immunology , Lymphoproliferative Disorders/etiology , Lymphoproliferative Disorders/immunology , Lymphoproliferative Disorders/virology , Male , Polymorphism, Genetic
11.
Transplant Proc ; 37(5): 2263-5, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15964394

ABSTRACT

INTRODUCTION: Pancreatic islet transplantation (PIT) has only become an effective treatment for type 1 diabetes mellitus within the past 4 years. As a result, the long-term effects of PIT on progression of diabetic neuropathy and retinopathy are unknown. The benefit of halting or improving diabetic neuropathy and retinopathy is of particular interest since most PIT recipients have not developed the advanced complications of diabetes. Herein, we describe the improvement and stabilization of diabetic neuropathy and retinopathy in 12 PIT recipients. PATIENTS AND METHODS: Between January 1, 2002, and June 30, 2004, there have been 12 patients who have received PIT. Currently, there are eight patients who have sufficient follow-up to assess the progression of diabetic retinopathy and neuropathy. To assess for disease progression, patients were examined by a single ophthalmologist and single neurologist throughout the study period. Eye exams were performed using a slit-lamp exam while neurological status was assessed using electromyelograms and clinical exams. RESULTS: All PIT recipients had decreases in hemoglobin A(1)C and increases in serum C-peptide. All study patients had stabilization of their retinopathic disease. One patient demonstrated improvement of retinopathy at 1 year posttransplant. Fifty percent of patients demonstrated improvement or stabilization of their diabetic neuropathy. One patient had mild reinnervation of the fingers and wrist extensors by clinical exam 1 year posttransplant. Four patients exhibited an average decrease of 19% in sural nerve conduction velocities. CONCLUSION: Our series has demonstrated that all PIT recipients have had stabilization of their diabetic retinopathy and that 50% of patients exhibited stabilization or even improvement of their diabetic neuropathy.


Subject(s)
Diabetes Mellitus, Type 1/surgery , Diabetic Neuropathies/prevention & control , Diabetic Retinopathy/prevention & control , Islets of Langerhans Transplantation/physiology , Adult , C-Peptide/blood , Diabetic Neuropathies/physiopathology , Diabetic Retinopathy/physiopathology , Female , Humans , Male , Middle Aged , Neurologic Examination
12.
Eur J Pediatr Surg ; 15(6): 434-6, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16418964

ABSTRACT

We report here on a newborn infant who initially presented with a history of gastroschisis, abdominal distension, and jaundice. Further studies revealed that the child had findings consistent with extrahepatic biliary atresia (EHBA). The child later developed hepatic failure and subsequently expired. The purpose of this case report is to discuss the pathogenesis of each disease process and to identify any commonality between the pathogenesis of gastroschisis and EHBA.


Subject(s)
Biliary Atresia/diagnosis , Gastroschisis/diagnosis , Biliary Atresia/etiology , Biliary Atresia/pathology , Fatal Outcome , Female , Gastroschisis/epidemiology , Gastroschisis/etiology , Humans , Infant, Newborn , Risk Factors
13.
Transplant Proc ; 36(4): 1127-9, 2004 May.
Article in English | MEDLINE | ID: mdl-15194393

ABSTRACT

BACKGROUND: Owing to advances in both immunosuppressive protocols and pancreatic islet isolation techniques, insulin independence has recently been achieved in type 1 insulin-dependent diabetics (IDDM) via pancreatic islet transplantation (PIT). Although the dissemination of immunosuppressive protocols is relatively easy, transferring the knowledge and expertise required to isolate a large number of quality human islets for transplantation is a far greater challenge. Therefore, in an attempt to centralize the critical islet processing needed for islet transplantation and to avoid the development of another islet processing center, we have established a collaborative islet transplant program between two geographically distant transplant centers. PATIENTS AND METHODS: Eleven consecutive type 1 IDDM patients with a history of severe hypoglycemia and metabolic instability underwent PIT at the Methodist Hospital (TMH) in Houston, Texas, utilizing pancreatic islets isolated at the Diabetes Research Institute (DRI) at the University of Miami in Miami, Florida between January 1, 2002 and June 31, 2003. Forty-one pancreata have been procured in the Houston area and have subsequently been transported for isolation at the DRI following enzymatic ductal perfusion by the automated method (Ricordi chamber). Following purification the islets were immediately transported back to TMH in Houston and transplanted via percutaneous transhepatic portal infusion. Immunosuppression regimen consisted of sirolimus, tacrolimus, and daclizumab. RESULTS: Following harvesting, donor pancreata arrived at the DRI for initiation of the isolation process within 6.5 hours of cross-clamping (median time 5.4 hours; range 4.8 to 6.5 hours). The islets were immediately transported back to TMH for final sterility and viability tests and transplanted via percutaneous transhepatic portal vein infusion. The harvesting of 41 pancreata has yielded a number of pancreatic islets sufficient for transplantation (>5000 IEQ/kg recipient body weight) 26 times (63% of harvested pancreata). Thus far, three patients have received three PITs and eight patients have received two PITs. Six remain insulin independent. All have experienced a decrease in serum hemoglobin A(1c) levels, and both basal and stimulated C-peptide levels have increased. There have been no major complications related to the procedure or the immunosuppressive regimen used. CONCLUSIONS: Our series demonstrates that pancreatic islets isolated at a remote isolation center can successfully and safely be used for PIT and the achievement of insulin independence.


Subject(s)
Diabetes Mellitus, Type 1/surgery , Islets of Langerhans Transplantation/adverse effects , Islets of Langerhans Transplantation/physiology , Adult , Diabetes Mellitus, Type 1/drug therapy , Female , Florida , Humans , Insulin/therapeutic use , Islets of Langerhans/cytology , Male , Middle Aged , Postoperative Complications/classification , Retrospective Studies , Texas
15.
Transplantation ; 72(11): 1853-8, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11740404

ABSTRACT

BACKGROUND: Split-liver transplantation offers a unique opportunity to expand the existing donor pool. However, it has previously been stated that due to inadequate liver volume the advantages of split-liver transplantation would be lost when attempting to split the liver for two adult recipients. In this study, we sought to determine the safety, efficacy, and applicability of split-liver transplantation in select adult liver transplant recipients. METHODS: Liver allografts for eight adult recipients were procured by in situ splitting of four adult cadaveric livers. The donor ages were 17, 19, 22, and 25 years and weights were 72, 77, 78, and 87 kg, respectively. In situ splitting resulted in three right trisegmental grafts, one right lobe graft, one left lobe graft, and three left lateral segmental grafts. The median recipient age was 49 years (range 38-61 years), whereas the median recipient weight was 84 kg (range 78-98 kg) for the right-sided grafts and 52 kg (range 51-53 kg) for recipients of the left-sided grafts. The median graft-to-recipient body weight ratio for right trisegmental, right lobe, left lobe, and left lateral segmental grafts was 1.31%, 1.26%, 1.35%, and 0.70%, respectively. RESULTS: Overall patient and graft survival in this series is 100%. All prothrombin times were normalized within 4 days of transplantation. No evidence of ascites or prolonged hyperbilirubinemia was encountered in any right- or left-sided graft recipient. The incidence of hepatic artery, portal vein, and hepatic vein thrombosis is 0%, 0%, and 0%, respectively. Hepatic arterial anastomotic bleeding and a cut surface bile leak each occurred in one patient. Median United Network for Organ Sharing (UNOS) waiting time was 242 days (range 4-454 days) for the patients to which the donor liver was allocated. In contrast, the median waiting time for the four patients receiving the extra split-liver graft was reduced significantly to 37 days (range 21-101 days) (P<0.02). CONCLUSIONS: This study demonstrates that split-liver transplantation can expand the cadaveric donor liver pool available for select adult liver transplant recipients. When both the donor organ and the transplant recipient are chosen carefully, split-liver transplantation can be safely performed without a delay in allograft function, increase in technical complications, or compromise in graft or patient survival.


Subject(s)
Health Care Rationing/methods , Liver Transplantation/methods , Tissue and Organ Procurement/methods , Adolescent , Adult , Cadaver , Humans , Middle Aged , Retrospective Studies , Survival Analysis , Treatment Outcome
16.
Transplantation ; 70(1): 94-9, 2000 Jul 15.
Article in English | MEDLINE | ID: mdl-10919581

ABSTRACT

BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is a serious complication associated with the use of chronic immunosuppression for solid organ transplantation. This study represents a retrospective analysis of UCLA's experience with PTLD in all pediatric liver transplant recipients between 1984-1997. We assessed the clinical presentation, risk factors, incidence density, immunological characteristics, management, and outcome of patients who developed PTLD when receiving either primary cyclosporin A (CsA) or tacrolimus. METHODS: A total of 251 children received primary CsA therapy of which 70 required OKT3 for steroid resistant rejection and 29 required tacrolimus rescue for OKT3 resistance and/or chronic rejection. One hundred forty one children received tacrolimus as primary therapy. Sixty patients who survived for less than 6 months after transplantation were excluded from the study. RESULTS: The total incidence density (ID) rate of PTLD was 1.8+/-0.4 per 100 patient-years (30/392). The overall ID rate of PTLD in the CsA group was 0.93+/-0.2 per 100 patient-years (15/251). Within this group of primary CsA-treated patients, the ID rate of PTLD was 0.49+/-0.1 without OKT3 or tacrolimus, 0.67+/-0.2 with OKT3, and 6.42+/-1.1 with tacrolimus rescue. The overall PTLD ID rate in the primary tacrolimus-treated patients was 4.86+/-1.2 per 100 person-years (15/141). There was a 5-fold increase in the ID rate of PTLD in the primary tacrolimus group when compared to the comparable, primary CsA group (P<0.001). The mean time to PTLD was 5-fold longer (49.7+/-20.7 months) in the CsA group when compared to the CsA/tacrolimus rescue group (9.8+/-3 months, P<0.05) or the tacrolimus primary group (12.6+/-5.1 months, P<0.05). Five patients had monoclonal disease in the CsA group, but only one in the tacrolimus group (P<0.05). Clinical presentations with enlarged lymph nodes, fevers, malaise, anorexia, weight loss, hypoalbuminemia, and gastrointestinal blood loss were common. Mortality was 20%, three patients died in each group. CONCLUSION: The use of primary tacrolimus therapy was associated with a significant 5-fold higher rate of PTLD when compared to those treated with primary cyclosporine. Early diagnosis, decrease and/or discontinuation of potent immunosuppressive agents may contribute to decrease morbidity and mortality of this entity.


Subject(s)
Immunosuppressive Agents/adverse effects , Liver Transplantation/adverse effects , Lymphoproliferative Disorders/etiology , Adolescent , Age Factors , Child , Child, Preschool , Cyclosporine/adverse effects , Herpesvirus 4, Human/isolation & purification , Humans , Incidence , Infant , Lymphoproliferative Disorders/epidemiology , Lymphoproliferative Disorders/therapy , Muromonab-CD3/adverse effects , Retrospective Studies , Risk Factors , Tacrolimus/adverse effects
17.
Transplantation ; 68(8): 1206-9, 1999 Oct 27.
Article in English | MEDLINE | ID: mdl-10551654

ABSTRACT

Congenital anatomic anomalies often present technical obstacles during liver transplants. Biliary atresia is the most common indication for liver transplants in children, and approximately 7-10% of these patients have congenital anomalies comprising the "polysplenia syndrome." The polysplenia syndrome, which often includes abdominal situs inversus, is of particular concern in liver transplants because these anatomic anomalies result in a more complex hepatectomy, alterations in the placement of the donor grafts, and the need for additional vascular reconstruction. Earlier reports have shown mixed results for these patients who have undergone orthotopic liver transplants, reporting a high rate of postoperative complications and poor survival. The use of living-related donor grafts has produced excellent results in the general pediatric population. This is the first report of the successful use of a living-related donor graft for an orthotopic liver transplant to treat end-stage liver disease secondary to biliary atresia in a child with polysplenia syndrome.


Subject(s)
Liver Transplantation , Spleen/abnormalities , Spleen/surgery , Biliary Atresia/complications , Biliary Atresia/etiology , Biliary Atresia/surgery , Female , Humans , Infant , Living Donors , Medical Illustration , Spleen/pathology
18.
J Surg Res ; 84(1): 1-7, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-10334880

ABSTRACT

BACKGROUND: We have previously shown that >75% of LEW cardiac allografts survive indefinitely in BUF rats pretreated at Day -21 intrathymically (IT) with donor alloantigen in conjunction with a single intravenous dose of ALS. Spleen cells can adoptively transfer the tolerant state to new cohorts of test recipients. This study was designed to analyze cellular and humoral events contributing to the "infectious" tolerance pathway in this model. METHODS: Spleen cells (25 x 10(6)) harvested from BUF recipients bearing long-term cardiac allografts were injected intravenously into lightly irradiated (450 R) secondary BUF rats, followed 24 h later by transplantation of LEW of ACl hearts. Cardiac allografts were then analyzed serially by reverse transcription polymerase chain reaction for Th1 and Th2 cytokine gene expression. Donor-specific IgM and IgG alloantibody responses in host serum were screened by flow cytometry. RESULTS: Transfer of regulatory spleen cells harvested between Days 80 and 140 from tolerant hosts induced tolerance to heart grafts in a donor-specific manner. In the early posttransplant period, selective sparing of Th2 cytokines was noted. Adoptively transferred hosts showed overall depression of IgM, but a vigorous IgG1 and IgG2a alloantibody response. CONCLUSION: IT + ALS-induced tolerance can be transferred in a donor-specific "infectious" manner to new cohorts of engrafted recipients. The development of tolerance is nontemporally bound, and associates with an early Th2-type immune deviation at the graft site. The elevated levels of T cell-dependent IgG1 and IgG2 may interfere with the antigen reactivity and alloresponsive effector functions, contributing to graft acceptance in the "infectious" tolerance pathway.


Subject(s)
Heart Transplantation/immunology , Immune System/physiopathology , Immune Tolerance/physiology , Infections/immunology , Thymus Gland/immunology , Animals , Antibody Formation/physiology , Cytokines/metabolism , Isoantibodies/immunology , Kinetics , Male , Rats , Rats, Inbred Strains , Th1 Cells/metabolism , Th2 Cells/metabolism , Transplantation Immunology/physiology , Transplantation, Homologous/immunology
19.
Ann Surg ; 229(3): 313-21, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10077042

ABSTRACT

OBJECTIVE: This study reviews the indications, technical aspects, and experience with ex vivo and in situ split liver transplantation. BACKGROUND: The shortage of cadaveric donor livers is the most significant factor inhibiting further application of liver transplantation for patients with end-stage liver disease. Pediatric recipients, although they represent only 15% to 20% of the liver transplant registrants, suffer the greatest from the scarcity of size-matched cadaveric organs. Split liver transplantation provides an ideal means to expand the donor pool for both children and adults. METHODS: This review describes the evolution of split liver transplantation from reduced liver transplantation and living-related liver transplantation. The two types of split liver transplantation, ex vivo and in situ, are compared and contrasted, including the technique, selection of patients for each procedure, and the most current results. RESULTS: Ex vivo splitting of the liver is performed on the bench after removal from the cadaver. It is usually divided into two grafts: segments 2 and 3 for children, and segments 4 to 8 for adults. Since 1990, 349 ex vivo grafts have been reported. Until recently, graft and patient survival rates have been lower and postoperative complication rates higher in ex vivo split grafts than in whole organ cadaveric transplantation. Further, the use of ex vivo split grafts has been relegated to the elective adult patient because of the high incidence of graft dysfunction (right graft) when placed in an emergent patient. Reasons for the poor function of ex vivo splits except in elective patients have focused on graft damage due to prolonged cold ischemia times and rewarming during the long benching procedure. In situ liver splitting is accomplished in a manner identical to the living donor procurement. This technique for liver splitting results in the same graft types as in the ex vivo technique. However, graft and patient survival rates reported for in situ split livers have exceeded 85% and 90%, respectively, with a lower incidence of postoperative complications, including biliary and reoperation for bleeding. These improved results have also been observed in the urgent patient. CONCLUSION: Splitting of the cadaveric liver expands the donor pool of organs and may eliminate the need for living-related donation for children. Recent experience with the ex vivo technique, if applied to elective patients, results in patient and graft survival rates comparable to whole-organ transplantation, although postoperative complication rates are higher. In situ splitting provides two grafts of optimal quality that can be applied to the entire spectrum of transplant recipients: it is the method of choice for expanding the cadaver liver donor pool.


Subject(s)
Liver Transplantation/methods , Adolescent , Child , Hepatectomy/methods , Humans , Tissue Donors
20.
Transplantation ; 67(3): 404-11, 1999 Feb 15.
Article in English | MEDLINE | ID: mdl-10030286

ABSTRACT

BACKGROUND: Poor linear growth after pediatric orthotopic liver transplantation (OLT) is a well-described phenomenon. We have undertaken a bivariate and multivariate analysis of multiple factors that might effect postOLT growth in all children who underwent transplantation at a single center, with survival > 1 year and adequate follow-up. METHODS: Standardized height score (Z score) and height deficit (centimeters below the 50th percentile) were computed for each patient over time. The variables assessed were (i) age at OLT, (ii) gender, (iii) pretransplantation diagnosis, (iv) Z score and height deficit at OLT, (v) tacrolimus versus cyclosporine as primary immunosuppressive therapy, (vi) retransplantation, (vii) graft disease, (viii) chronic illness, (ix) posttransplant lymphoproliferative disease, (x) intractable rejection, and (xi) prednisone withdrawal. RESULTS: A total of 236 children met the inclusion criteria, with a mean follow-up of 3.8+/-1.9 years. For the population as a whole, the baseline Z score was -1.72 (fourth percentile) with a significant improvement to - 1.37 (ninth percentile) at 2 years, but with no additional gain at 5 years (Z score -1.4). The baseline height deficit was -6.4 cm, with no improvement at 2 years (-6.52 cm), and was significantly worse at 5 years (-7.87 cm). In the bivariate analysis, the most important variables affecting growth were age at OLT, Z score at OLT, and diagnosis. In general, children <2 years with biliary atresia and those with the most growth delay at OLT showed the best posttransplantation growth. In the multivariate analysis, 18 factors were considered, of which 9 were significant. These were (i) Z score at baseline, (ii) follow-up time, (iii) age at OLT, (iv) diagnosis of tumor, (v) diagnosis of fulminant hepatic failure, (vi) retransplantation, (vii) graft disease, (viii) posttransplant lymphoproliferative disease, and (ix) stoppage of prednisone. Multivariate models using these nine variables accounted for 84% of the variation in standardized height. CONCLUSION: In general, children after OLT show some potential for catch-up growth but do not achieve normal height compared with their age and sex-matched peers. A multivariate analysis was necessary to investigate the interdependent effects of the many variables that can affect growth after OLT. The most important detrimental affects were older age at time of OLT, Z scores greater than -2.0 at OLT, fulminant hepatic failure, tumor, and postOLT complications causing graft dysfunction.


Subject(s)
Body Height , Growth/physiology , Liver Transplantation/physiology , Adolescent , Age Factors , Child , Child, Preschool , Cyclosporine/therapeutic use , Female , Follow-Up Studies , Hospital Records , Humans , Immunosuppressive Agents/therapeutic use , Infant , Male , Postoperative Complications , Reoperation , Retrospective Studies , Sex Factors , Survival Analysis , Tacrolimus/therapeutic use , Time Factors
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