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2.
Transplantation ; 72(11): 1853-8, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11740404

RESUMO

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.


Assuntos
Alocação de Recursos para a Atenção à Saúde/métodos , Transplante de Fígado/métodos , Obtenção de Tecidos e Órgãos/métodos , Adolescente , Adulto , Cadáver , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
3.
Transplantation ; 69(8): 1690-4, 2000 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-10836382

RESUMO

BACKGROUND: Fas ligand (FasL) induces apoptosis of cells bearing Fas receptor, and may play a role in the acquisition of immune privilege. We have previously shown that adenovirus (Ad)-mediated FasL gene transfer significantly prolongs survival in a strongly major histocompatibility complex-incompatible rat kidney allograft model. This study analyzes putative mechanisms of FasL-mediated effects, with particular emphasis on Th1 and Th2 immune activation and Bag-1 expression, a Bcl-2-binding anti-apoptotic protein. METHODS: Kidney transplants were performed in Wistar-Furth to Lewis rat combination. Donor kidneys were perfused in situ with Ad-FasL or Ad-beta-Gal, and then transplanted. Kidney allografts were harvested at days 2, 7, and 56 and were evaluated by hematoxylin and eosin and immunohistochemical staining. The expression of FasL, Bag-1, and Th1/Th2 cytokine genes was assessed by Northern blots, Western blots, and competitive template reverse-transcriptase polymerase chain reaction, respectively. RESULTS: Intragraft expression of FasL was enhanced, whereas that of anti-apoptotic Bag-1 gene was diminished throughout, in Ad-FasL-transduced well-functioning renal allografts, compared with Ad-beta-Gal-treated rejecting controls. In parallel, the expression of mRNA coding for IL-2 and IFN-gamma remained depressed, whereas that of IL-4 and IL-10 reciprocally and progressively increased in the Ad-FasL animal group. CONCLUSIONS: Prolonged survival in Ad-FasL-transduced rat renal allograft model correlates with down-regulation of Bag-1, a novel anti-apoptotic gene, and preferential Th2-type cytokine elaboration profile at the graft site. Because Th1-like cells are sensitive to FasL-mediated cytotoxic effects, T-cell apoptosis may preferentially spare Th2-like cells, with resultant prolonged graft survival.


Assuntos
Proteínas de Transporte/metabolismo , Citocinas/metabolismo , Técnicas de Transferência de Genes , Sobrevivência de Enxerto , Transplante de Rim , Glicoproteínas de Membrana/genética , Células Th2/metabolismo , Animais , Apoptose/fisiologia , Proteínas de Transporte/fisiologia , Citocinas/genética , Proteínas de Ligação a DNA , Regulação para Baixo/fisiologia , Proteína Ligante Fas , Expressão Gênica , Rim/metabolismo , Rim/fisiologia , Masculino , Glicoproteínas de Membrana/metabolismo , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos WF , Fatores de Transcrição , Transplante Homólogo
4.
Transplantation ; 67(3): 422-30, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10030290

RESUMO

To formulate a model predicting survival after liver retransplantation, we analyzed in detail the last 150 cases of hepatic retransplantation at UCLA. Cox proportional hazards regression analysis identified five variables that demonstrated independent simultaneous prognostic value in estimating patient survival after retransplantation: (1) age group (pediatric or adult), (2) recipient requiring preoperative mechanical ventilation, (3) donor organ cold ischemia > or =12 hr, (4) preoperative serum creatinine, and (5) preoperative serum total bilirubin. The Cox regression equation that predicts survival based on these covariates was simplified by assigning individual patients a risk classification based on a 5-point scoring system. We demonstrate that this system can be employed to identify a subgroup of patients in which the expected outcome is too poor to justify retransplantation. These findings may assist in the rational selection of patients suitable for retransplantation.


Assuntos
Transplante de Fígado/mortalidade , Reoperação/mortalidade , Adulto , Fatores Etários , California , Criança , Intervalos de Confiança , Seguimentos , Hospitais Universitários , Humanos , Isquemia , Fígado , Modelos Estatísticos , Análise Multivariada , Preservação de Órgãos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Doadores de Tecidos
5.
Am J Gastroenterol ; 93(11): 2245-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9820407

RESUMO

Recurrent hepatitis B infection after orthotopic liver transplantation remains problematic despite prophylaxis with hepatitis B immune globulin (anti-HBs IgG). Recently, famciclovir (an oral nucleoside analog) has been shown to have potent antiviral activity against hepatitis B in vitro as well as in patients with chronic hepatitis B. We present two patients who developed recurrent hepatitis B after orthotopic liver transplantation and were treated with famciclovir, 500 mg t.i.d. Both patients subsequently responded with marked improvement in biochemical liver tests and histology, with subsequent loss of hepatitis B surface antigen. Famciclovir is a useful agent in the treatment of hepatitis B in the liver transplant recipient.


Assuntos
2-Aminopurina/análogos & derivados , Antivirais/uso terapêutico , Hepatite B/tratamento farmacológico , Transplante de Fígado , 2-Aminopurina/uso terapêutico , Famciclovir , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Recidiva
6.
Ann Surg ; 228(3): 411-20, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9742924

RESUMO

OBJECTIVE: To analyze a single center's 13-year experience with 569 pediatric orthotopic liver transplants for end-stage liver disease. SUMMARY BACKGROUND DATA: Despite advances in medical therapy, liver replacement continues to be the only definitive mode of therapy for children with end-stage liver disease. Innovative surgical techniques and improved immunosuppression have broadened the application of liver replacement for affected children. However, liver transplantation in the child remains challenging because of the scarcity of donor organs, complex surgical technical demands, and the necessity to prevent long-term complications. METHODS: The medical records of 440 consecutive patients younger than 18 years of age undergoing orthotopic liver transplantation for end-stage liver disease from March 20, 1984, to November 15, 1997, were reviewed. Results were analyzed using Cox multivariate regression analysis to determine the statistical strength of independent associations between pretransplant covariates and patient and graft survival. Actuarial patient and graft survival rates were determined at 1, 3, 5, and 10 years. The type and incidence of posttransplant complications were determined, as was the quality of long-term allograft function. The median follow-up period was 4.1 years. RESULTS: Biliary atresia was the most common cause (50.4%) of endstage liver disease in this patient population. The median recipient age was 2.4 years; 239 patients (54%) were younger than 3 years of age and 1 11 patients (25%) were younger than 1 year of age. There were 471 whole organs, 29 were ex vivo reduced size, 33 were living-related donor, and 36 were in situ split-liver allografts. Three hundred forty-three (78%) patients underwent a single allograft, whereas 97 patients required retransplantation; hepatic artery thrombosis was the most common indication for retransplantation (55 patients). The 1-, 3-, 5-, and 10-year actuarial patient survival rates were 82%, 80%, 78%, and 76%, respectively; allograft survival rates were 68%, 63%, 60%, and 54%. Long-term liver function remains excellent: current median follow-up values for total bilirubin and aspartate aminotransferase were 0.5 mg/dl and 54 IU/L, respectively. Cox multivariate regression analysis demonstrated that pretransplant patient age, the era of transplantation, and the number of allografts performed significantly and independently predicted patient survival rates, whereas allograft type and pretransplant diagnosis did not. CONCLUSIONS: Liver transplantation in the pediatric patient is a durable procedure that provides excellent long-term survival. Although there have been overall improvements in patient outcome with increased experience, the effect is most pronounced for patients younger than 1 year of age. Retransplantation, although effective in a meaningful number of patients, continues to carry a progressive decrement in survival with the number of allografts performed. Use of living-related and in situ split-liver allografts has dramatically reduced waiting times for small children and has improved patient survival.


Assuntos
Falência Hepática/cirurgia , Transplante de Fígado , Análise Atuarial , Adolescente , Criança , Pré-Escolar , Seguimentos , Sobrevivência de Enxerto , Humanos , Terapia de Imunossupressão , Lactente , Falência Hepática/mortalidade , Transplante de Fígado/efeitos adversos , Análise Multivariada , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , Fatores de Tempo
8.
Liver Transpl Surg ; 4(5): 350-4, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9724471

RESUMO

The purpose of this study was to combine our clinical experience with a review of the literature to determine the value of orthotopic liver transplantation in the treatment of both boys and girls with ornithine transcarbamylase deficiency. Three boys younger than 1 year of age with symptomatic ornithine transcarbamylase deficiency (median age, 116 days; range, 40 to 223 days) underwent orthotopic liver transplantation. The patients' growth, developmental progress, ammonia levels, and amino acid levels were analyzed pre- and post-liver transplantation. The clinical courses of the respective patients and the treatment modalities used were compared with published reports from 1978 through 1997. The median follow-up period in these 3 patients was 3.2 years (range, 9 months to 5.2 years). Orthotopic liver transplantation restored normal urea production and stabilized ammonia levels within 24 hours of surgery (median serum ammonia level 24 hours post-liver replacement, 43 micromol/L; range, 30 to 66 micromol/L). After liver replacement, arginine synthesis was normalized; however, plasma citrulline levels remained less than normal in all patients. Linear growth was evaluated in all 3 patients at the time of the most recent follow-up; median z scores for patient height and weight were -2.16 and -1.16, respectively. Standardized intelligence tests showed that 2 of the 3 patients continue to perform at age-appropriate levels. The third child was developmentally delayed pretransplantation at 4 months of age on presentation and continues to perform in a below-average fashion. Orthotopic liver transplantation results in the restoration of normal urea production and serum ammonia levels in the boy suffering from symptomatic ornithine transcarbamylase deficiency. Serum arginine, but not citrulline, levels are normalized, probably because of the persistent intestinal mucosa defect. Patient growth is similar to that in infants undergoing liver transplantation for other causes. When liver transplantation is performed before cognitive impairment occurs, intellectual development is normal, because the risk of additional episodes of hyperammonemia is elevated.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/cirurgia , Amônia/sangue , Arginina/sangue , Transplante de Fígado , Doença da Deficiência de Ornitina Carbomoiltransferase , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Transplante Homólogo , Ureia/sangue
9.
Hepatology ; 28(2): 412-5, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9696005

RESUMO

Polycystic liver disease, commonly associated with polycystic kidney disease, can result in massive hepatomegaly and debilitating symptoms. Surgical intervention for symptomatic polycystic liver disease has been associated with significant morbidity and inconsistent long-term palliation; it is more appropriate in patients with a single dominant cyst or cysts which is/are confined to one lobe. At our institution, nine patients have undergone orthotopic liver transplantation for symptomatic hepatic cysts with excellent long-term results and minimal morbidity and mortality. Surgical candidates were selected based on severe limitations in daily activities and on sequelae of hepatic cystic involvement. Other factors considered were the extent and pattern of hepatic cystic disease, the degree of hepatic and renal dysfunction, and prior surgical intervention. Three patients (33%) required combined liver and kidney transplantation because of renal cystic involvement with renal insufficiency. The one-year survival rate was 89% with excellent symptomatic relief and improved quality of life in all the surviving patients. One death occurred in a significantly malnourished 62-year-old female. Complications included one case each of hepatic artery thrombosis requiring retransplantation, biliary leak necessitating biliary reconstruction, and postoperative bleeding requiring re-exploration. The mean hospital stay was 23 days and the mean intraoperative blood transfusion requirement was 18 units. Our experience demonstrates that appropriately selected patients with extensive hepatic involvement with adult polycystic liver disease can have an excellent outcome with transplantation, with morbidity comparable with other surgical options.


Assuntos
Cistos/cirurgia , Hepatopatias/cirurgia , Transplante de Fígado , Adulto , Cistos/diagnóstico por imagem , Feminino , Humanos , Hepatopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Hepatology ; 28(2): 585-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9696028

RESUMO

Patients undergoing liver transplantation for hepatitis B-related liver disease are prone to recurrence. The mainstay of prophylaxis has been passive immunotherapy with hepatitis B immune globulin (HBIG). Antiviral therapy with lamivudine has proven effective in lowering hepatitis B virus (HBV) DNA and improving histology in patients with hepatitis B infection; its role in prophylaxis against hepatitis B recurrence following liver transplantation is under investigation. Viral breakthrough and resistance, however, are a significant problem with monotherapy with either HBIG or lamivudine. The efficacy of combination lamivudine/HBIG prophylaxis has not been reported. Fourteen patients underwent transplantation for decompensated liver disease owing to hepatitis B. Lamivudine (150 mg p.o./d) was begun before transplantation in 10 patients, including 4 who were HBV DNA-positive. In addition, 1 patient was HBV DNA-positive when transplanted. HBIG was given perioperatively and continued thereafter; treatment with lamivudine was maintained or initiated at the time of transplantation and continued indefinitely. The median follow-up was 387 days. Actuarial 1-year patient and graft survival was 93% (1 patient died of unrelated causes). At a median interval of 28 days following lamivudine treatment, all 5 HBV DNA-positive patients cleared HBV DNA from the serum; 1 went on to clear hepatitis B surface antigen (HBsAg), before transplantation, at day 148 of lamivudine treatment. By the highly sensitive polymerase chain reaction (PCR), at a median of 346 days (range, 130-525 days) following transplantation, all 13 surviving patients had no detectable serum HBV DNA. Lamivudine suppresses HBV replication in patients awaiting liver transplantation. At a median follow-up of 1.1 years, combination prophylaxis with lamivudine and HBIG prevented hepatitis B recurrence following liver transplantation.


Assuntos
Hepatite B/prevenção & controle , Imunização Passiva , Lamivudina/uso terapêutico , Transplante de Fígado , Complicações Pós-Operatórias/prevenção & controle , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Idoso , Feminino , Seguimentos , Hepatite B/terapia , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Humanos , Imunoglobulinas , Fígado/fisiopatologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Prevenção Secundária , Replicação Viral/efeitos dos fármacos
12.
Arch Surg ; 133(8): 839-46, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9711957

RESUMO

OBJECTIVE: To review the clinical characteristics, outcomes, and risk factors for survival among 57 pediatric patients undergoing orthotopic liver transplantation for fulminant hepatic failure at the University of California, Los Angeles, Center for the Health Sciences. DESIGN: The medical records of 57 consecutive pediatric patients undergoing orthotopic liver transplantation for fulminant hepatic failure from July 1, 1984, to June 25, 1997, were reviewed and survival data were analyzed via univariate and multivariate statistical methods. The type and incidence of posttransplant complications were determined as was the quality of long-term graft function. Median follow-up period was 3.38 years (range, 0-10.02 years). RESULTS: The 1-, 3-, and 5-year actuarial patient survival rates were 77%, 77%, and 77%, respectively, while graft survivals were 73%, 65%, and 65%. Stepwise Cox regression analysis revealed that recipient age and ventilator dependency at the time of transplantation were independently and significantly correlated with patient survival, whereas no association was found between survival and grade of encephalopathy, prior abdominal surgery, recipient weight, pretransplantation values for total bilirubin or prothrombin time, ABO match, allograft type, peak posttransplantation aspartate aminotransferase levels, or the presence of posttransplantation hepatic artery thrombosis. Non-ventilator-dependent patients demonstrated a 96% 1-, 3-, and 5-year survival as compared with only 56% at these same time points for those children requiring ventilator support at the time of transplantation (P < .001). At the time of most recent follow-up, median values for total bilirubin and aspartate aminotransferase concentrations were 10.3 micromol/L (0.6 mg/dL) and 56 U/L, respectively, in the 40 surviving patients. CONCLUSIONS: In children undergoing liver transplantation for fulminant hepatic failure: (1) overall results are comparable to those achieved for less emergent non-neoplastic indications in this same age group; (2) ventilator dependency prior to transplantation is the strongest predictor of ultimate survival, followed by recipient age; (3) 5-year survival exceeds 90% in recipients who are ventilator independent immediately prior to liver transplantation but is significantly compromised once the need for mechanical ventilation supervenes, particularly in those younger than 4 years; and (4) prompt referral and timely liver replacement are the cornerstones of optimal outcome.


Assuntos
Encefalopatia Hepática/cirurgia , Transplante de Fígado , Análise Atuarial , Adolescente , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Encefalopatia Hepática/mortalidade , Humanos , Lactente , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Análise de Sobrevida , Resultado do Tratamento
15.
Transplantation ; 65(4): 570-2, 1998 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-9500634

RESUMO

BACKGROUND: Although jejunoileal bypass results in end-stage liver disease in up to 100% of patients, little is known about outcome after liver transplantation. METHODS: The clinical courses of six patients who underwent liver transplantation at UCLA for decompensated cirrhosis owing to a jejunoileal bypass were reviewed. Liver function, allograft pathology, renal function, and nutritional status were assessed. RESULTS: Of the four patients with an intact jejunoileal bypass, two of the three who were biopsied had recurrent steatotic liver disease. The two patients whose jejunoileal bypass was reversed at the time of liver transplantation had lower alkaline phosphatase, lower creatinine, higher albumin, and higher cholesterol, and were more obese than their counterparts with intact bypasses. CONCLUSIONS: Patients undergoing liver transplantation for jejunoileal bypass-associated liver disease should, if possible, have their bypass reversed at the time of transplantation; otherwise, they must be followed closely and be biopsied routinely. Recurrent liver disease should prompt reversal of the jejunoileal bypass.


Assuntos
Derivação Jejunoileal/efeitos adversos , Cirrose Hepática/cirurgia , Transplante de Fígado , Adulto , Biópsia , Feminino , Seguimentos , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Recidiva
16.
Transplantation ; 65(1): 68-72, 1998 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9448146

RESUMO

BACKGROUND: We retrospectively reviewed 213 consecutive patients who received their first liver allograft between January 1 and December 31, 1993, in order to study the impact of ischemia/preservation/reperfusion injury (IPRI) on patient and graft outcome. METHODS: The extent of IPRI was assessed by the peak value of aspartate aminotransferase (ASTmax) observed within the first 72 hr after transplant. For the purpose of univariate analysis, categorical classification of recipients was done based upon ASTmax as follows: group 1, ASTmax<600 U/L (n=46); group 2, ASTmax=600-2000 U/L (n=97); group 3, ASTmax>2000-5000 U/L (n=50), and group 4, ASTmax>5000 U/L (n=17). For multivariate analysis, stepwise Cox regression was performed with age, ASTmax, and United Network for Organ Sharing (UNOS) status as covariates. RESULTS: Groups were comparable with respect to age, UNOS status at the time of transplantation, and diagnostic case mix. Median follow-up was 644 days. The overall incidence of primary graft nonfunction (PNF) was 7.6%. PNF incidence was significantly correlated with the severity of IPRI (0%, 4%, 10%, and 41% for groups 1 to 4, respectively, P < 0.0001), but this impact was confined to the respective rates of retransplantation as early patient survival was unaffected. The 1-year survival of patients whose initial grafts manifested extreme IPRI (group 4) was significantly inferior to recipients in the three other groups (77%, 71%, 73%, and 52% for groups 1 to 4, respectively, P=0.03). This increased mortality was confined to patients who never achieved discharge from their initial hospitalization, with no significant differences between groups being detected in the survival of those patients who were discharged (84%, 80%, 85%, and 81% for groups 1 to 4, respectively, P=NS). Although overall 1-year graft survival was strongly correlated with the extent of IPRI (77%, 67%, 62%, and 41% for groups 1 to 4, respectively, P=0.001), this correlation was abolished when survival of grafts not lost to PNF was examined at 1 and 2 years. Stepwise Cox regression analysis confirmed the independent association between ASTmax and patient and graft survival. The long-term quality of allograft function as well as the incidence of chronic rejection and biliary complications were unrelated to the extent of IPRI. CONCLUSIONS: We conclude that: (1) patient survival is influenced by IPRI only when it is extreme (ASTmax>5000 U/L), provided parameters of graft function are used in conjunction with aminotransferase values to assess the need for prompt retransplantation; (2) short-term graft survival is proportional to the extent of IPRI, but grafts that are not lost to PNF have equivalent 1- and 2-year survival irrespective of the magnitude of IPRI; (3) 40% of grafts with extreme IPRI are lost to PNF, but the same proportion also provide long-term function; and (4) for surviving grafts, long-term biochemical function as well as the incidence of biliary complications and of chronic rejection are unrelated to the extent of IPRI.


Assuntos
Aspartato Aminotransferases/metabolismo , Transplante de Fígado , Adulto , Sistema Biliar/fisiopatologia , Ciclosporina/uso terapêutico , Feminino , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Imunossupressores/uso terapêutico , Fígado/enzimologia , Transplante de Fígado/fisiologia , Masculino , Muromonab-CD3/uso terapêutico , Estudos Retrospectivos , Tacrolimo/uso terapêutico
17.
Transplantation ; 65(2): 149-55, 1998 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9458006

RESUMO

BACKGROUND: Pravastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, inhibits coronary transplant vasculopathy in the clinical setting. To further delineate the immune modulatory effect of this agent, it was tested in a rat cardiac transplant model of chronic rejection. METHODS: Rat heterotopic abdominal cardiac transplants were performed using a Lewis to Fischer 344 combination. Fischer 344 recipients received a brief course of cyclosporine to decrease the incidence of acute rejection. Experimental groups were treated with either high-dose (10 mg/kg) or low-dose (5 mg/kg) pravastatin for 120 days, while a control group did not receive pravastatin. The effect of pravastatin on chronic rejection of cardiac allografts was analyzed by histology, and the expression of laminin, fibronectin, macrophages, and T cells was assessed by immunohistochemistry. RESULTS: Coronary transplant vasculopathy was inhibited in both groups of pravastatin-treated animals, as compared with controls. Immunohistochemistry revealed that control animals had degraded laminin and fibronectin which paralleled the degree of tissue necrosis. In contrast, pravastatin-treated animals had modest amounts of extracellular matrix proteins retained within intermyocytes and endothelium, a pattern seen in native cardiac tissue. The pravastatin-treated groups also had fewer graft-infiltrating macrophages, specifically within the arterial intima and perivascular areas. CONCLUSIONS: Progressive chronic vascular rejection, a leading cause of allograft failure, can be inhibited by pravastatin in a well-defined rat cardiac transplant model. Pravastatin appears to inhibit the synthesis and subsequent degradation of extracellular matrix proteins and block the infiltration of macrophages to the graft, which emphasizes that this inflammatory cell plays a major role in the pathogenesis of transplant chronic rejection.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transplante de Coração/imunologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Pravastatina/farmacologia , Animais , Proteínas da Matriz Extracelular/metabolismo , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/patologia , Transplante de Coração/patologia , Imuno-Histoquímica , Macrófagos , Masculino , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Transplante Homólogo
18.
Transplantation ; 65(2): 155-60, 1998 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9458007

RESUMO

BACKGROUND: Fas ligand (FasL) induces apoptosis of cells bearing its receptor Fas, and has been shown to be important in T-cell development and regulation and in immune privilege. We hypothesized that FasL expression by renal allografts might provide protection from rejection. METHODS: The murine FasL cDNA was cloned into a replication-defective adenovirus (AdV-FasL). Protein expression was confirmed by immunostaining of AdV-FasL-transduced HeLa cells. Allogeneic kidney transplants were performed between WF (RT1u) donors and Lewis (RT1) recipients. Donor kidneys were perfused in situ with saline alone (control), or 9 x 10(9) plaque-forming units of AdV-FasL. One native kidney was removed at the time of transplant and the other at 6 or 7 days. Uremic death was the endpoint, and deaths within 7 days of transplant were excluded. Transduced allografts were stained for FasL expression using a monoclonal antibody and tested for FasL mRNA production by reverse transcriptase-polymerase chain reaction and Northern blotting. RESULTS: Immunostaining of AdV-FasL-transduced allografts demonstrated efficient gene transfer lasting approximately 2 weeks, and FasL mRNA production in the AdV-FasL-transduced allografts was confirmed by Northern blotting and reverse transcriptase-polymerase chain reaction. Mean survival of animals with AdV-FasL-transduced renal allografts was 27.8 days vs. 11.6 days in control animals (P < 0.05). CONCLUSIONS: (1) Adenoviral vectors can successfully transduce rat kidneys with the FasL cDNA. (2) FasL gene transfer prolongs rat renal allograft survival.


Assuntos
Citotoxicidade Imunológica , Rejeição de Enxerto/metabolismo , Sobrevivência de Enxerto , Transplante de Rim/imunologia , Glicoproteínas de Membrana , Transplante Homólogo/imunologia , Adenoviridae , Animais , Citotoxicidade Imunológica/genética , DNA Complementar , Proteína Ligante Fas , Técnicas de Transferência de Genes , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Células HeLa , Humanos , Imuno-Histoquímica , Transplante de Rim/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos WF , Transdução Genética , Transplante Homólogo/patologia
19.
Ann Surg ; 226(4): 408-18; discussion 418-20, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9351709

RESUMO

OBJECTIVE: The authors determined the long-term outcome of patients undergoing hepatic retransplantation at their institution. Donor, operative, and recipient factors impacting on outcome as well as parameters of patient resource utilization were examined. SUMMARY BACKGROUND DATA: Hepatic retransplantation provides the only available option for liver transplant recipients in whom an existing graft has failed. However, such patients are known to exhibit patient and graft survival after retransplantation that is inferior to that expected using the same organs in naiive recipients. The critical shortage of donor organs and resultant prolonged patient waiting periods before transplantation prompted the authors to evaluate the results of a liberal policy of retransplantation and to examine the factors contributing to the inferior outcome observed in retransplanted patients. METHODS: A total of 2053 liver transplants were performed at the UCLA Medical Center during a 13-year period from February 1, 1984, to October 1, 1996. A total of 356 retransplants were performed in 299 patients (retransplant rate = 17%). Multivariate regression analysis was performed to identify variables associated with survival. Additionally, a case-control comparison was performed between the last 150 retransplanted patients and 150 primarily transplanted patients who were matched for age and United Network of Organ Sharing (UNOS) status. Differences between these groups in donor, operative, and recipient variables were studied for their correlation with patient survival. Days of hospital and intensive care unit stay, and hospital charges incurred during the transplant admissions were compared for retransplanted patients and control patients. RESULTS: Survival of retransplanted patients at 1, 5, and 10 years was 62%, 47%, and 45%, respectively. This survival is significantly less than that seen in patients undergoing primary hepatic transplantation at the authors' center during the same period (83%, 74%, and 68%). A number of variables proved to have a significant impact on outcome including recipient age group, interval to retransplantation, total number of grafts, and recipient UNOS status. Recipient primary diagnosis, cause for retransplantation, and whether the patient was retransplanted before or after June 1, 1992, did not reach statistical significance as factors influencing survival. In the case-control comparison, the authors found that of the more than 25 variables studied, only preoperative ventilator status showed both a significant difference between control patients and retransplanted patients and also was a factor predictive of survival in retransplanted patients. Retransplant patients had significantly longer hospital and intensive care unit stays and accumulated total hospitalization charges more than 170% of those by control patients. CONCLUSIONS: Hepatic retransplantation, although life-saving in almost 50% of patients with a failing liver allograft, is costly and uses scarce donor organs inefficiently. The data presented define patient characteristics and preoperative variables that impact patient outcome and should assist in the rational application of retransplantation.


Assuntos
Transplante de Fígado , Adolescente , Adulto , Estudos de Casos e Controles , Causas de Morte , Humanos , Readmissão do Paciente , Análise de Regressão , Reoperação , Análise de Sobrevida , Fatores de Tempo , Doadores de Tecidos , Resultado do Tratamento
20.
Transplantation ; 64(6): 871-7, 1997 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-9326413

RESUMO

BACKGROUND: The shortage of cadaveric donor livers is the rate-limiting step in clinical liver transplantation. Split liver transplantation provides a means to expand the cadaveric donor pool. However, this concept has not reached its full potential because of inferior patient and graft survival and high complication rates when traditional ex vivo split techniques are used. Therefore we sought to evaluate the safety, applicability, and effectiveness of a new technique for split liver transplantation. METHODS: This study consists of 15 in situ split liver procurements, which resulted in 28 liver transplants. In situ splitting of selected livers from hemodynamically stable cadaveric donors was performed at the donor hospital without any additional work-up or equipment being needed. In situ liver splitting is accomplished in a manner identical to the living-donor procurement. This technique for liver splitting results in a left lateral segment graft (segments 2 and 3) and a right trisegmental graft (segments 1 and 4-8). This procedure required the use of the donor hospital operating room for an additional 1.5-2.5 hr and did not interfere with the procurement of 30 kidneys, 12 hearts, 7 lungs, and 9 pancreata from these same donors. RESULTS: The 6-month and 1-year actuarial patient survival rates were 92% and 92%, respectively, while the 6-month and 1-year actuarial graft survival rates were 86% and 86%, respectively. The 6-month and 1-year actuarial patient survival rate of patients who received a left lateral segment graft was 100% and 100%, respectively, while those who received a right trisegmental graft had 6-month and 1-year rates of 86% and 86%, respectively. The actuarial death-censored graft survival rates at 6 months and 1 year were 80% and 80%, respectively, for the left lateral segment grafts, and 93% and 93%, respectively, for the right trisegmental grafts. Alograft and patient survival was independent of United Network for Organ Sharing status at the time of liver transplantation. No patient developed a biliary stricture, required re-exploration for intra-abdominal hemorrhage, or suffered from portal vein, hepatic vein, or hepatic artery thrombosis CONCLUSIONS: In situ split liver transplantation can be accomplished without complications and provides results that are superior to those obtained previously with ex vivo methods. It abolishes ex vivo benching and prolonged ischemia times and provides two optimal grafts with hemostasis accomplished. This technique decreases pediatric waiting time and allows adult recipients to receive right-sided grafts safely. In situ splitting is the method of choice for expanding the cadaveric liver donor pool.


Assuntos
Sobrevivência de Enxerto , Hepatectomia/métodos , Transplante de Fígado/métodos , Análise Atuarial , Adulto , Cadáver , Coração , Hemodinâmica , Humanos , Rim , Transplante de Fígado/mortalidade , Transplante de Fígado/fisiologia , Doadores Vivos , Pulmão , Pâncreas , Complicações Pós-Operatórias , Segurança , Taxa de Sobrevida , Fatores de Tempo , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/organização & administração , Estados Unidos
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