Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 108
Filtrar
1.
Am J Transplant ; 16(11): 3235-3245, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27192971

RESUMO

The demand for liver transplantation (LT) exceeds supply, with rising waiting list mortality. Utilization of high-risk organs is low and a substantial number of procured livers are discarded. We report the first series of five transplants with rejected livers following viability assessment by normothermic machine perfusion of the liver (NMP-L). The evaluation protocol consisted of perfusate lactate, bile production, vascular flows, and liver appearance. All livers were exposed to a variable period of static cold storage prior to commencing NMP-L. Four organs were recovered from donors after circulatory death and rejected due to prolonged donor warm ischemic times; one liver from a brain-death donor was declined for high liver function tests (LFTs). The median (range) total graft preservation time was 798 (range 724-951) min. The transplant procedure was uneventful in every recipient, with immediate function in all grafts. The median in-hospital stay was 10 (range 6-14) days. At present, all recipients are well, with normalized LFTs at median follow-up of 7 (range 6-19) months. Viability assessment of high-risk grafts using NMP-L provides specific information on liver function and can permit their transplantation while minimizing the recipient risk of primary graft nonfunction. This novel approach may increase organ availability for LT.


Assuntos
Transplante de Fígado , Fígado/metabolismo , Preservação de Órgãos , Perfusão/métodos , Doadores de Tecidos/provisão & distribuição , Sobrevivência de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Adulto , Idoso , Aloenxertos , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Humanos , Fígado/irrigação sanguínea , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Disfunção Primária do Enxerto/prevenção & controle , Isquemia Quente
2.
Am J Transplant ; 16(10): 2816-2835, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27273869

RESUMO

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.


Assuntos
Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Isoanticorpos/imunologia , Transplante de Fígado/efeitos adversos , Aloenxertos , Humanos , Relatório de Pesquisa
3.
Postgrad Med J ; 89(1058): 685-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23924687

RESUMO

BACKGROUND: Fibroscan is a quick, non-invasive technique used to measure liver stiffness (kPa), which correlates with fibrosis. To achieve a valid liver stiffness evaluation (LSE) the operator must obtain all the following three criteria: (1) ≥10 successful liver stiffness measurements; (2) IQR/median ratio <0.30 and (3) ≥60% measurement success rate. OBJECTIVES: To assess the operator training requirements and the importance of adhering to the LSE validity criteria in routine clinical practice. METHODS: We retrospectively analysed the LSE validity rates of 2311 Fibroscans performed (1 August 2008 to 31 July 2011) in our tertiary liver outpatients department at the University Hospital Birmingham, UK. The diagnostic accuracy of Fibroscan was assessed in 153 patients, by comparing LSE (valid and invalid) with the modified Ishak fibrosis stage on liver biopsy. RESULTS: Learning curve analysis highlighted that the greatest improvement in validity of LSE rates occurs in the operator's first 10 Fibroscans, reaching 64.7% validity by the 50th Fibroscan. The correlation between LSE and the fibrosis stage on liver biopsy was superior in patients with a valid LSE (n=97) compared with those with an invalid LSE (n=56) (rs 0.577 vs 0.259; p=0.022). Area under receiving operating characteristics for significant fibrosis was greater when LSE was valid (0.83 vs 0.66; p=0.048). Using an LSE cut-off of 8 kPa, the negative predictive value of valid LSE was superior to invalid LSE for the detection of significant (84% vs 71%) and advanced fibrosis (100% vs 93%). CONCLUSIONS: Fibroscan requires minimal operator training (≥10 observed on patients), and when a valid LSE is obtained, it is an accurate tool for excluding advanced liver fibrosis. To ensure the diagnostic accuracy of Fibroscan it is essential that the recommended LSE validity criteria are adhered to in routine clinical practice.


Assuntos
Competência Clínica , Técnicas de Imagem por Elasticidade , Fidelidade a Diretrizes , Pessoal de Saúde/educação , Cirrose Hepática/diagnóstico , Fígado/patologia , Área Sob a Curva , Biópsia , Competência Clínica/normas , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Inglaterra , Feminino , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Medicina Estatal
4.
J Exp Med ; 189(2): 441-6, 1999 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-9892626

RESUMO

We propose that a novel mechanism of hepatocyte apoptosis, involving a cooperative interaction between CD40 and Fas, is involved in the hepatocyte loss of chronic liver allograft rejection. We detected increased hepatocyte expression of Fas, Fas ligand (FasL), and CD40 associated with dropout of centrilobular (acinar zone 3) hepatocytes in chronic allograft rejection. Expression of CD40 ligand (CD40L) was also increased but was largely restricted to CD68(+) macrophages. A functional role for CD40 and Fas in hepatocyte apoptosis was demonstrated in vitro using primary human hepatocytes and the HepG2 cell line in both of which apoptosis was induced, not only by cross-linking Fas directly but also via CD40 activation. Our data suggest that CD40 activation induces apoptosis via Fas because (a) ligation of CD40 upregulated hepatocyte FasL expression, and (b) apoptosis induced via activation of CD40 was prevented by a neutralizing monoclonal antibody to FasL. Thus, CD40 engagement triggers apoptosis of human hepatocytes and might amplify Fas-dependent hepatocyte apoptosis in chronic rejection and other inflammatory liver diseases in which Fas-mediated apoptosis is involved.


Assuntos
Apoptose/fisiologia , Antígenos CD40/metabolismo , Rejeição de Enxerto/imunologia , Fígado/imunologia , Glicoproteínas de Membrana/metabolismo , Transplante Homólogo/imunologia , Anticorpos Monoclonais/farmacologia , Linhagem Celular , Proteína Ligante Fas , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Inflamação/imunologia , Fígado/patologia , Microscopia de Fluorescência
5.
Am J Transplant ; 8(9): 1931-41, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18671674

RESUMO

Late allograft dysfunction is a significant problem following liver transplantation and its pathogenesis is uncertain. HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that regulate the cytotoxic activity of natural killer (NK) cells. HLA-C alleles can be allocated into two groups, termed HLA-C1 and HLA-C2, based on their KIR specificity. HLA-C2 interactions are more inhibiting to NK cell activation. We studied the clinical importance of HLA-C genotype in a large liver transplant cohort and found that possession of at least one HLA-C2 allele by the donor allograft was associated with less histological evidence of chronic rejection and graft cirrhosis, a 16.2% reduction in graft loss (p = 0.003) (hazard ratio: 2.7, 95% CI 1.4-5.3) and a 13.6% improvement in patient survival (p = 0.01) (hazard ratio: 1.9, 95% CI 1.1-3.3) at 10 years. Transplantation of an HLA-C2 homozygous allograft led to a particularly striking 26.5% reduction in graft loss (p < 0.001) (hazard ratio: 7.2, 95% CI 2.2-23.0) at 10 years when compared to HLA-C1 homozygous allografts. Donor HLA-C genotype is therefore a major determinant of clinical outcome after liver transplantation and reveals the importance of NK cells in chronic rejection and graft cirrhosis. Modulation of HLA-C and KIR interactions represents an important novel approach to promote long-term graft and patient survival.


Assuntos
Rejeição de Enxerto/epidemiologia , Antígenos HLA-C/genética , Transplante de Fígado/imunologia , Doadores de Tecidos , Adulto , Alelos , Estudos de Coortes , Feminino , Fibrose/epidemiologia , Fibrose/patologia , Seguimentos , Genótipo , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/genética , Heterozigoto , Teste de Histocompatibilidade , Homozigoto , Humanos , Incidência , Estimativa de Kaplan-Meier , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/transplante , Masculino , Análise Multivariada , Receptores KIR/imunologia , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologia
7.
Aliment Pharmacol Ther ; 47(5): 631-644, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29271504

RESUMO

BACKGROUND: Validated diagnostic tools that are accurate, cost effective and acceptable to patients are required for disease stratification and monitoring in NAFLD. AIMS: To investigate the performance and cost of multiparametric MRI alongside existing biomarkers in the assessment of NAFLD. METHODS: Adult patients undergoing standard of care liver biopsy for NAFLD were prospectively recruited at two UK liver centres and underwent multiparametric MRI, blood sampling and transient elastography withing 2 weeks of liver biopsy. Non-invasive markers were compared to histology as the gold standard. RESULTS: Data were obtained in 50 patients and 6 healthy volunteers. Corrected T1 (cT1) correlated with NAFLD activity score (ρ = 0.514, P < .001). cT1, enhanced liver fibrosis (ELF) test and liver stiffness differentiated patients with simple steatosis and NASH with AUROC (95% CI) of 0.69 (0.50-0.88), 0.87 (0.77-0.79) and 0.82 (0.70-0.94) respectively and healthy volunteers from patients with AUROC (95% CI) of 0.93 (0.86-1.00), 0.81 (0.69-0.92) and 0.89 (0.77-1.00) respectively. For the risk stratification of NAFLD, multiparametric MRI could save £150,218 per 1000 patients compared to biopsy. Multiparametric MRI did not discriminate between individual histological fibrosis stages in this population (P = .068). CONCLUSIONS: Multiparametric MRI accurately identified patients with steatosis, stratifies those with NASH or simple steatosis and reliably excludes clinically significant liver disease with superior negative predictive value (83.3%) to liver stiffness (42.9%) and ELF (57.1%). For the risk stratification of NAFLD, multiparametric MRI was cost effective and, combined with transient elastography, had the lowest cost per correct diagnosis.


Assuntos
Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adolescente , Adulto , Idoso , Biópsia , Análise Custo-Benefício , Técnicas de Imagem por Elasticidade/economia , Técnicas de Imagem por Elasticidade/métodos , Feminino , Voluntários Saudáveis , Humanos , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/economia , Imageamento por Ressonância Magnética/economia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/economia , Hepatopatia Gordurosa não Alcoólica/patologia , Valor Preditivo dos Testes , Adulto Jovem
8.
FASEB J ; 15(13): 2345-54, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11689460

RESUMO

Fas-mediated mechanisms of apoptosis are thought to be involved in the bile duct loss that characterizes diseases such as primary biliary cirrhosis (PBC). We have previously shown that activation of CD40 on hepatocytes can amplify Fas-mediated apoptosis; in the present study, we investigated interactions between CD40 and Fas in biliary epithelial cells (BEC). We report that the bile ducts in PBC liver tissue frequently express increased levels of Fas, Fas ligand (FasL), and CD40 associated with apoptotic BEC. The portal mononuclear infiltrate contains CD40L+ve T cells and macrophages, thereby demonstrating a potential mechanism for CD40 engagement in vivo. Primary cultures of human BEC also expressed Fas, FasL, and CD40 but not CD40L protein or mRNA. Activation of CD40 on BEC using recombinant CD40L increased transcriptional expression of FasL and induced apoptosis, which was inhibited by neutralizing antibodies to either Fas or FasL. Thus, CD40-induced apoptosis of BEC is mediated through Fas/FasL. We then investigated the intracellular signals and transcription factors activated in BEC and found that NF-kappaB and AP-1 were both activated after CD40 ligation. Increased functional NF-kappaB was seen early after CD40 ligation, but returned to baseline levels after 4 h. In contrast, the rapid up-regulation of AP-1 was sustained over 24 h. This study provides further functional evidence of the ability of CD40 to induce Fas/FasL-dependent apoptosis of liver epithelial cells supporting the importance of cross-talk between tumor necrosis factor (TNF) receptor family members as an amplification step in apoptosis induction. Sustained activation of AP-1 in the absence of NF-kappaB signaling may be a critical factor in determining the outcome of CD40 engagement.


Assuntos
Apoptose/fisiologia , Ductos Biliares Intra-Hepáticos/fisiologia , Antígenos CD40/metabolismo , NF-kappa B/fisiologia , Fator de Transcrição AP-1/fisiologia , Receptor fas/fisiologia , Ductos Biliares Intra-Hepáticos/química , Ductos Biliares Intra-Hepáticos/citologia , Antígenos CD40/genética , Ligante de CD40/metabolismo , Ligante de CD40/farmacologia , Células Cultivadas , Células Epiteliais/química , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Proteína Ligante Fas , Imunofluorescência , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Cirrose Hepática Biliar/metabolismo , Cirrose Hepática Biliar/patologia , Cirrose Hepática Biliar/fisiopatologia , Macrófagos/química , Macrófagos/patologia , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/genética , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Linfócitos T/química , Linfócitos T/patologia , Fatores de Tempo , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima , Receptor fas/análise
9.
Transplantation ; 71(11): 1566-72, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11435966

RESUMO

BACKGROUND: The progression of parenchymal changes in liver allograft biopsies due to preservation-reperfusion injury (PRI) and their differentiation from rejection related changes is poorly understood. The aim of this study was to determine which changes in a 1-week posttransplant biopsy could be attributed to PRI and which to acute rejection. METHODS: One week protocol liver transplant biopsies from patients with mild PRI (day 1 AST<400 IU/L) were compared with those from patients with severe PRI (day 1 AST>2000 IU/L). Parenchymal changes (cholestasis, ballooning, steatosis, necrosis) and rejection-related inflammatory features (portal tract inflammation, bile duct inflammation, portal vein endothelial inflammation, hepatic vein endothelial inflammation, and centrilobular inflammation) were blindly assessed semiquantitatively. RESULTS: Fat, cholestasis, and hepatocyte ballooning were significantly worse in the severe PRI group, and these features showed no correlation with histological features related to acute rejection. Centrilobular hepatocyte necrosis correlated with hepatic venular endothelial inflammation and centrilobular inflammation but not with rejection related features in portal tracts or with PRI. These findings suggest that centrilobular necrosis is a manifestation of a rejection-related parenchymal injury and may involve different pathogenetic mechanisms to rejection-related features in portal tracts. CONCLUSIONS: This study indicates that in early posttransplant biopsies, fat, cholestasis, and ballooning can largely be attributed to PRI. By contrast, centrilobular hepatocyte loss should be suspected as a rejection related phenomenon, even if typical portal tract changes are not prominent, and augmentation of immunosuppression should be considered.


Assuntos
Rejeição de Enxerto/patologia , Circulação Hepática , Transplante de Fígado , Fígado/patologia , Preservação Biológica/efeitos adversos , Traumatismo por Reperfusão/patologia , Adolescente , Adulto , Idoso , Biópsia , Colestase/patologia , Criopreservação , Fígado Gorduroso/patologia , Feminino , Hepatócitos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
10.
Transplantation ; 47(3): 479-82, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2493698

RESUMO

Hepatic endothelial cell damage was evaluated in patients following liver transplantation using 2 serum markers: hyaluronic acid (HA), which measures hepatic endothelial cell function, and factor VIII related antigen (VIIIRAg), an indicator of generalized endothelial damage. HA was elevated in rejection (median 22.3 x control) when compared with stable patients (3.7 x control; P less than 0.00001) and those with posttransplant complications not related to rejection (6.8 x control; P less than 0.0005). The highest levels were seen in patients with chronic rejection (28.7 x control). Levels were also elevated in acute rejection (21.3 x control), and the highest levels in this group were seen in patients who subsequently developed chronic rejection (25.2 x control). Serial studies demonstrated that HA increased 24 hr before serum bilirubin in patients developing acute rejection. VIIIRAg was elevated in all posttransplant patients with no significant difference between rejection and other complications. These results show that hepatic endothelial dysfunction occurs during acute and particularly chronic rejection of liver allografts suggesting that VECs may be an important target of the immune response. Measurement of HA may allow for the early diagnosis of acute rejection and the identification of patients at risk of developing chronic rejection.


Assuntos
Fígado/citologia , Adolescente , Adulto , Idoso , Antígenos/análise , Creatinina/sangue , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Fator VIII/análise , Fator VIII/imunologia , Feminino , Antígenos HLA/imunologia , Humanos , Ácido Hialurônico/sangue , Masculino , Pessoa de Meia-Idade , Fator de von Willebrand
11.
Transplantation ; 68(2): 253-6, 1999 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10440397

RESUMO

BACKGROUND: The literature data on the recurrence of autoimmune hepatitis (AIH) after orthotopic liver transplantation (OLTX) is scanty. METHODS: We analyzed the frequency of recurrent AIH in 47 patients who had been transplanted for AIH and survived at least 1 year after surgery. The following criteria were applied to diagnose recurrence: (1) positive autoantibodies in the titer> or =1:40; (2) hypertransaminasemia; (3) histological features of chronic hepatitis; (4) need of reintroduction or significant increase of steroids; and (5) lack of serum markers of viral hepatitis. RESULTS: A total of 13 patients (1 male/12 females) developed recurrent AIH after an interval of 6-63 months after OLTX (mean 29 months). Mean AST level at recurrence was 542+/-129 U/L. Three patients from this group needed regrafting. Mismatch of DR3+ recipient and DR3- donor was not more common in the recurrent disease group (37%) compared to the nonrecurrence group (31%) (P=NS). CONCLUSIONS: Recurrence of AIH after OLTX was diagnosed in a high proportion of patients and some of them required regrafting. DR3+ patients are not particularly prone to develop recurrence.


Assuntos
Hepatite Autoimune/prevenção & controle , Hepatite Autoimune/cirurgia , Transplante de Fígado , Análise de Variância , Anticorpos Antinucleares/sangue , Aspartato Aminotransferases/sangue , Biópsia , Feminino , Rejeição de Enxerto/diagnóstico , Hepatite Autoimune/patologia , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Recidiva , Fatores de Tempo
12.
Transplantation ; 70(3): 477-80, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10949190

RESUMO

BACKGROUND/AIM: It remains uncertain whether autoimmune hepatitis (AIH), as an original indication for orthotopic liver transplantation (OLTX), predisposes to the development of chronic rejection (CR) after surgery and published reports on heterogeneous groups of patients provided conflicting data. In this work we analyzed the incidence and risk factors for CR in a large cohort of adult patients transplanted for AIH in our unit. RESULTS: A total of 1190 adult patients received OLTX in our center between 1982 and 1998. A total of 77 patients (6.5%) were transplanted for AIH and 12 (15.6%) patients from this group developed clinical and histological features of CR within a median time of 3.5 months after OLTX. Patients with AIH who developed CR were younger than other AIH patients at OLTX (32 vs. 44.2 ys; P=0.015) and more often had histological features of moderate or severe acute rejection (83 vs. 34%; P=0.002) on early post-OLTX biopsies. The incidence of CR in AIH patients was significantly higher than in subjects transplanted for other indications such as primary biliary cirrhosis (8.2%; P<0.05), primary sclerosing cholangitis (5.2%; P<0.05) or alcoholic cirrhosis (2.0%; P<0.001). Also, we observed a tendency to decreased incidence of CR with time in all transplanted subjects. CONCLUSIONS: Apart from younger age at OLTX and higher incidence of severe acute rejection, patients with AIH who developed CR did not differ from other subjects transplanted for this indication. Unlike other studies, not stratified by diagnosis, recipient CMV negative status, young donor age, and HLA DR matching were not identified as risk factors for CR in AIH.


Assuntos
Doenças Autoimunes/cirurgia , Rejeição de Enxerto/etiologia , Hepatite/cirurgia , Transplante de Fígado/efeitos adversos , Adulto , Doenças Autoimunes/complicações , Colangite Esclerosante/cirurgia , Doença Crônica , Estudos de Coortes , Feminino , Hepatite/complicações , Hepatite Viral Humana/cirurgia , Humanos , Cirrose Hepática Biliar/cirurgia , Hepatopatias Alcoólicas/cirurgia , Masculino , Fatores de Risco
13.
Transplantation ; 51(5): 1004-10, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1851580

RESUMO

Loss of bile ducts is a characteristic feature of chronic rejection in the liver allograft (also known as irreversible rejection and vanishing bile-duct syndrome). Typically, this occurs as a progressive lesion resulting in irreversible damage and graft failure requiring retransplantation. In this study, we describe 6 patients who developed a transient loss of bile ducts following liver transplantation. This occurred in a series of 138 patients who underwent the first 160 liver transplant operations in the Birmingham Liver Transplant Programme (incidence = 4.4% of patients, 3.7% of grafts). Forty needle biopsies were obtained from the 6 patients between 6 and 1303 days after transplantation. Thirteen specimens, taken between 8 and 1253 days posttransplant (median 98 days) showed an absence of bile ducts in more than 50% of portal tracts. Other histologic features of chronic rejection, inflammatory bile-duct lesions, perivenular cholestasis, and hepatocyte dropout were also seen in these biopsies, and severe cholestasis was present biochemically (median serum bilirubin level 240 mumol/L). The histologic and biochemical changes were thought to be compatible with a diagnosis of chronic/irreversible rejection, but the decision to carry out retransplantation was deferred on the basis of stable and, subsequently, improving biochemistry. Follow-up biopsies showed recovery of duct loss and other histologic abnormalities. All 6 patients are currently alive and well with good graft function. It is concluded that a transient, reversible bile-duct loss can occur after liver transplantation and that cases with this condition are indistinguishable from those who subsequently develop irreversible graft damage. In view of the risks associated with additional immunosuppression and/or retransplantation, caution is advocated in the interpretation of ductopenia in posttransplant liver biopsies. We suggest that the term "early chronic rejection" might be appropriate to describe cases in which a definite diagnosis of irreversible graft damage cannot be made.


Assuntos
Doenças dos Ductos Biliares/etiologia , Rejeição de Enxerto , Transplante de Fígado/efeitos adversos , Adolescente , Adulto , Idoso , Doenças dos Ductos Biliares/terapia , Ductos Biliares/patologia , Bilirrubina/sangue , Infecções por Citomegalovirus/etiologia , Feminino , Seguimentos , Antígenos HLA/análise , Humanos , Masculino
14.
Transplantation ; 60(10): 1098-103, 1995 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-7482715

RESUMO

Liver allograft rejection is usually divided into acute (cellular) rejection and chronic (ductopenic) rejection. Most cases of acute rejection occur within four weeks of transplantation. There is a paucity of published literature on late acute rejection (LAR) in liver allografts and little is known about factors affecting its occurrence and outcome. To study the predisposing factors, clinical presentation, and prognosis of LAR, data prospectively collected on consecutive adult patients who underwent liver transplantation between 1982 and 1994, were analyzed. LAR was defined as histologically confirmed acute cellular rejection occurring 30 or more days after liver transplantation. Of the 717 patients, 59 (7.5%) had 71 episodes of LAR. Fifty-seven episodes were seen during the first year after transplantation, the remaining occurring between 1 and 6 years. Age, sex, pretransplant diagnosis, donor match of HLA, and blood groups was not associated with risk of LAR. Twenty-seven (38%) episodes were preceded by subtherapeutic blood levels of cyclosporine/FK506 (< 100 ng/ml and < 5 ng/ml, respectively) while an additional 6 (8%) had marginally low blood levels (< 150 ng/ml and < 10 ng/ml, respectively). Treatment with high-dose prednisolone resulted in complete resolution of rejection in 36 (51%) episodes, partial response in 21, and no response in 14 patients. Sixteen patients (27%) developed chronic rejection and graft loss. Development of chronic rejection was not affected by age or sex of the patient, timing of LAR, or histological severity of AR. Delayed response to therapy during an earlier episode of AR, and histological findings of centrilobular necrosis or bile duct loss at the time of diagnosis of LAR were associated with high risk of progression to chronic rejection and graft loss.


Assuntos
Rejeição de Enxerto , Transplante de Fígado/imunologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Tempo , Transplante Homólogo
15.
Transplantation ; 72(12): 1957-67, 2001 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-11773896

RESUMO

BACKGROUND: Graft rejection after liver transplantation is associated with a lymphocytic infiltrate, the nature of which will be determined by, among various factors, the local activity of chemokines that attract particular subsets of effector cells to the graft. METHODS: The expression of chemokines and receptors in human liver allografts was studied by immunohistochemistry of tissue and flow cytometry of blood and liver-derived lymphocytes. Receptor function was assessed with in vitro chemotaxis. RESULTS: We report increased expression of chemokine receptors CXCR3, CXCR4, and CCR5 on circulating and graft-infiltrating lymphocytes after liver transplantation. Liver-derived T cells responded to the ligands for these receptors in vitro, which suggests that the receptors are functionally active. The chemokine ligands for these receptors were detected in rejecting allografts. CXCR3 ligands interferon-inducible protein 10 and monokine-induced by gamma interferon were detected on sinusoidal endothelium and interferon-inducible T-cell alpha chemoattractant was detected on portal and hepatic vascular endothelium, whereas the CXCR4 ligand, stromal-derived factor (SDF), was restricted to biliary epithelium. CCR5 ligands have previously been shown on portal endothelium. An in vitro model of T-cell alloactivation demonstrated a similar pattern of expression of functional CXCR3, CXCR4, and CCR5 on T cells. Increased expression of chemokine receptors, especially CCR3 and CCR5, was associated with redistribution of activated Kupffer cells in rejecting grafts. CONCLUSIONS: The patterns of chemokine expression in liver allografts during rejection suggest that the recruitment and positioning of lymphocytes is mediated by specific chemokines. Although ligands for the receptors CXCR3 and CCR5 are important for recruitment, the restriction of SDF to bile ducts suggests that CXCR4 may be involved in the retention of alloactivated lymphocytes at sites of graft damage.


Assuntos
Quimiocinas/metabolismo , Rejeição de Enxerto/complicações , Hepatite/etiologia , Hepatite/metabolismo , Transplante de Fígado , Receptores de Quimiocinas/metabolismo , Quimiocina CXCL10/metabolismo , Quimiocina CXCL12 , Quimiocinas CXC/metabolismo , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/patologia , Humanos , Interferon-alfa/metabolismo , Células de Kupffer/metabolismo , Fígado/patologia , Linfócitos/metabolismo , Linfócitos/patologia , Período Pós-Operatório , Receptores CXCR3 , Receptores CXCR4/metabolismo , Receptores CXCR5 , Receptores de Citocinas/metabolismo , Linfócitos T/metabolismo
16.
Transplantation ; 55(3): 529-34, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8456473

RESUMO

A group of 195 consecutive adult patients who received a primary orthotopic liver allograft were reviewed retrospectively to analyze the incidence of rejection, the response to antirejection therapy, and the impact of acute rejection on the development of ductopenic rejection. The diagnosis of acute rejection (AR) was based on a combination of clinical and histological criteria, and 69.7% of the patients had at least one episode of acute rejection. Only 6.7% of the patients failed to respond to steroids and were treated with OKT3. Four (2.3%) patients developed acute vanishing bile duct syndrome (within 60 days) and 6 (3.5%) patients developed chronic rejection. Eight patients who spontaneously recovered from AR without additional immunosuppression are described in detail. In addition to histological damage, all developed significant hepatic dysfunction. Except for one patient who died from disseminated fungal infection, the 7 remaining patients are alive with excellent graft function 7 to 21 months posttransplant. While severe AR and recurrent AR should be treated without delay, some patients with mild-to-moderate rejection and hepatic dysfunction may resolve without additional immunosuppression.


Assuntos
Rejeição de Enxerto/terapia , Transplante de Fígado/imunologia , Doença Aguda , Adolescente , Adulto , Doenças dos Ductos Biliares/etiologia , Feminino , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/epidemiologia , Humanos , Imunossupressores/uso terapêutico , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome , Transplante Homólogo
17.
Transplantation ; 61(10): 1488-95, 1996 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-8633377

RESUMO

Alpha 1 antitrypsin deficiency (AT) is an autosomal recessive disease associated with chronic liver disease in adults and children and emphysema in adults. The disease is one of the most common inherited disorders of the Caucasian population of North Europe and North America and is the most common genetic reason for pediatric orthotopic liver transplantation (OLTx), although it is a rare indication in adults. The natural history of the disease is unpredictable and the pathogenesis of the liver injury unclear. Thirty-five patients with histologically apparent alpha 1 AT accumulation in the liver (22 adults, 13 children) have been transplanted in this center. Clinical features were correlated with the pretransplant phenotype, serum alpha 1 antitrypsin levels and potential precipitating factors. All children were PiZZ homozygotes, most of whom had presented with neonatal hepatitis. The majority of adult patients were heterozygotes presenting with portal hypertension and liver cirrhosis. Current one-year posttransplant survival figures are 73% for adults and 87.5% for children. Replacement of the cirrhotic liver results in acquisition of the donor phenotype, a rise in serum levels of alpha 1 antitrypsin, and apparent prevention of associated disease.


Assuntos
Hepatopatias/cirurgia , Transplante de Fígado , Deficiência de alfa 1-Antitripsina , Adulto , Humanos , Lactente , Recém-Nascido , Hepatopatias/enzimologia , Neoplasias Hepáticas/complicações , Pulmão/fisiologia , Pessoa de Meia-Idade , Recidiva
18.
Transplantation ; 57(9): 1323-7, 1994 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8184469

RESUMO

In a prospective study, 66 donor livers were evaluated by monoethylglycinexylidide (MEGX) dynamic clearance and semiquantitative scoring of pathological changes in liver biopsies. The median MEGX level in 63 donors was 89 mcg/L (range 16-250 mcg/L); fifteen had MEGX levels < 50 mcg/L, 17 between 50 and 90 mcg/L, and 31 > 90 mcg/L. There were no cases of primary nonfunction, and no deaths were related to poor graft function. There was no statistically significant difference in peak aspartate aminotransferase (AST), day 5 AST, peak bilirubin, or lowest prothrombin time among the 3 groups. Liver biopsies were assessed in 61 donors: 33 (54%) were normal and 17 (28%) showed mild, 8 (13%) showed moderate, and 3 (5%) showed severe steatosis. Postperfusion biopsy assessing the extent of preservation injury was essentially normal or showed minimal change in 16 (26%), mild change in 29 (48%), moderate in 13 (21%) and severe abnormalities in 3 (5%). The latter 3 biopsies all had severe steatosis. There was no significant difference in early graft function or outcome between moderate/severe groups and normal/minimal groups, although the former had a higher peak AST (P < 0.02) and peak bilirubin (P < 0.004). This detailed prospective analysis suggests that MEGX and the morphological studies may assist in the assessment of potential liver donors but they do not provide a basis on which grafts should be discarded.


Assuntos
Transplante de Fígado/patologia , Fígado/patologia , Doadores de Tecidos , Adolescente , Adulto , Aspartato Aminotransferases/metabolismo , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto/diagnóstico , Humanos , Lactente , Lidocaína/análogos & derivados , Lidocaína/farmacocinética , Fígado/metabolismo , Transplante de Fígado/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Transplantation ; 55(4): 789-94, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8475553

RESUMO

Corticosteroids were withdrawn from the immunosuppressive regimen of 168/197 (85%) of liver transplant patients who survived for more than three months. In 14, steroids were restarted for reasons other than rejection. The remaining 154 patients were evaluated for the occurrence of rejection and graft loss. Risk factors for the development of rejection after steroid withdrawal were assessed. There were 13 episodes of rejection in 12 (7.8%) grafts; 7 (4.5%) experienced acute cellular rejection, and 6 (3.9%) developed chronic ductopenic rejection. All cases of acute rejection resolved with high-dose steroids. Graft and patient loss due to chronic rejection was 3 (1.9%) and 2 (1.3%), respectively. Chronic rejection resolved in 1 patient, 1 was successfully retransplanted, and in the other 2 the principal cause of death was recurrent tumor. None of the risk factors examined (primary indication for transplant, severity of previous acute rejection, use of OKT3, retransplantation, ABO blood group donor/recipient match, CMV infection, and CsA mono versus CsA and AZA double therapy) were associated with the development of chronic rejection poststeroid withdrawal. The prevalence of side effects, after steroid withdrawal, was low; 66% of patients never required antihypertensive medication; 14% experienced a significant septic episode, and only 4 died with sepsis as the major factor. There were no fungal sepsis and no new cases of diabetes. Withdrawal of corticosteroids after 3 months can be successfully achieved in the majority of liver allograft recipients and is associated with a low rate of rejection, graft loss, and complications attributable to immunosuppressive medication.


Assuntos
Corticosteroides/administração & dosagem , Transplante de Fígado/imunologia , Prednisolona/efeitos adversos , Síndrome de Abstinência a Substâncias/etiologia , Adolescente , Adulto , Idoso , Azatioprina/farmacologia , Ciclosporina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Terapia de Imunossupressão/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo
20.
J Clin Pathol ; 42(11): 1160-5, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2584429

RESUMO

To determine whether portal lymphadenopathy in primary biliary cirrhosis is caused by deposition of lipofuscin pigment in sinus histiocytes and to compare primary biliary cirrhosis with other liver diseases a retrospective study on a consecutive series of 169 livers obtained at transplantation was carried out. There were grouped into eight diagnostic categories: primary biliary cirrhosis (n = 51), primary sclerosing cholangitis (n = 10), extrahepatic biliary atresia (n = 6), chronic rejection (n = 9), cirrhosis (other causes) (n = 38), primary liver neoplasia (n = 21), acute liver disease (n = 20), and retransplantation (other) (n = 14). Lymph nodes were present in 66 specimens. Fifty of these contained granules of lipofuscin pigment. The highest incidence of lymph node enlargement and the largest amounts of pigment were present in cases of primary biliary cirrhosis. A similar pattern of lymph node enlargement was also commonly observed in other chronic cholestatic conditions (primary sclerosing cholangitis, biliary atresia, chronic rejection). Much less pigment was seen in nodes draining livers with non-cholestatic cirrhosis or primary tumours. Nodes were not found in acute liver disease. It is concluded that portal lymphadenopathy associated with lipofuscin is a common finding in various chronic cholestatic liver diseases. The pathogenesis of this lesion is uncertain. Most cases are asymptomatic with enlarged nodes which may be detected only at laperotomy or necropsy and may be wrongly attributed to neoplastic disease. Diagnostically, the finding of large amounts of lipofuscin in enlarged portal lymph nodes is a good indicator of underlying chronic cholestatic liver disease.


Assuntos
Lipofuscina/análise , Cirrose Hepática Biliar/complicações , Linfonodos/análise , Doenças Linfáticas/metabolismo , Pigmentos Biológicos/análise , Colestase/complicações , Doença Crônica , Humanos , Fígado , Hepatopatias/complicações , Linfonodos/patologia , Doenças Linfáticas/etiologia , Doenças Linfáticas/patologia , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa