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1.
Am J Transplant ; 17(1): 11-21, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27214826

RESUMO

In spite of reduction of rejection rates and improvement in short-term survival post-kidney transplantation, modest progress has occurred in long-term graft attrition over the years. Timely identification of molecular events that precede clinical and histopathological changes might help in early intervention and thereby increase the graft half-life. Evolution of "omics" tools has enabled systemic investigation of the influence of the whole genome, epigenome, transcriptome, proteome and microbiome on transplant function and survival. In this omics era, systemic approaches, in-depth clinical phenotyping and use of strict validation methods are the key for further understanding the complex mechanisms associated with graft function. Systems biology is an interdisciplinary holistic approach that focuses on complex and dynamic interactions within biological systems. The complexity of the human kidney transplant is unlikely to be captured by a reductionist approach. It appears essential to integrate multi-omics data that can elucidate the multidimensional and multilayered regulation of the underlying heterogeneous and complex kidney transplant model. Herein, we discuss studies that focus on genetic biomarkers, emerging technologies and systems biology approaches, which should increase the ability to discover biomarkers, understand mechanisms and stratify patients and responses post-kidney transplantation.


Assuntos
Marcadores Genéticos , Transplante de Rim , Biologia de Sistemas , Genômica , Humanos , Proteômica , Transcriptoma
2.
Am J Transplant ; 17(12): 3060-3075, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28556588

RESUMO

Progressive fibrosis of the interstitium is the dominant final pathway in renal destruction in native and transplanted kidneys. Over time, the continuum of molecular events following immunological and nonimmunological insults lead to interstitial fibrosis and tubular atrophy and culminate in kidney failure. We hypothesize that these insults trigger changes in DNA methylation (DNAm) patterns, which in turn could exacerbate injury and slow down the regeneration processes, leading to fibrosis development and graft dysfunction. Herein, we analyzed biopsy samples from kidney allografts collected 24 months posttransplantation and used an integrative multi-omics approach to understand the underlying molecular mechanisms. The role of DNAm and microRNAs on the graft gene expression was evaluated. Enrichment analyses of differentially methylated CpG sites were performed using GenomeRunner. CpGs were strongly enriched in regions that were variably methylated among tissues, implying high tissue specificity in their regulatory impact. Corresponding to this methylation pattern, gene expression data were related to immune response (activated state) and nephrogenesis (inhibited state). Preimplantation biopsies showed similar DNAm patterns to normal allograft biopsies at 2 years posttransplantation. Our findings demonstrate for the first time a relationship among epigenetic modifications and development of interstitial fibrosis, graft function, and inter-individual variation on long-term outcomes.


Assuntos
Atrofia/patologia , Metilação de DNA , Fibrose/patologia , Rejeição de Enxerto/genética , Falência Renal Crônica/patologia , Transplante de Rim/métodos , Túbulos Renais/patologia , Adulto , Atrofia/metabolismo , Biomarcadores/metabolismo , Estudos de Coortes , Progressão da Doença , Feminino , Fibrose/metabolismo , Seguimentos , Perfilação da Expressão Gênica , Taxa de Filtração Glomerular , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/cirurgia , Testes de Função Renal , Túbulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Transplante Homólogo
3.
Am J Transplant ; 14(5): 1152-1163, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24698514

RESUMO

The molecular basis of calcineurin inhibitor toxicity (CNIT) in kidney transplantation (KT) and its contribution to chronic allograft dysfunction (CAD) with interstitial fibrosis (IF) and tubular atrophy (TA) were evaluated by: (1) identifying specific CNIT molecular pathways that associate with allograft injury (cross-sectional study) and (2) assessing the contribution of the identified CNIT signature in the progression to CAD with IF/TA (longitudinal study). Kidney biopsies from well-selected transplant recipients with histological diagnosis of CNIT (n = 14), acute rejection (n = 13) and CAD with IF/TA (n = 10) were evaluated. Normal allografts (n = 18) were used as controls. To test CNIT contribution to CAD progression, an independent set of biopsies (n = 122) from 61 KT patients collected at 3 and ~12 months post-KT (range = 9-18) were evaluated. Patients were classified based on 2-year post-KT graft function and histological findings as progressors (n = 30) or nonprogressors to CAD (n = 31). Molecular signatures characterizing CNIT samples were identified. Patients classified as progressors showed an overlap of 7% and 22% with the CNIT signature at 3 and at ~12 months post-KT, respectively, while the overlap was <1% and 1% in nonprogressor patients, showing CNIT at the molecular level as a nonimmunological factor involved in the progression to CAD.


Assuntos
Biomarcadores/sangue , Inibidores de Calcineurina/efeitos adversos , Perfilação da Expressão Gênica , Rejeição de Enxerto/classificação , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Aloenxertos , Área Sob a Curva , Estudos Transversais , Progressão da Doença , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/genética , Humanos , Falência Renal Crônica/complicações , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos
4.
Am J Transplant ; 14(2): 466-71, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24373228

RESUMO

Many transplant centers use endoscopically directed brachytherapy to provide locoregional control in patients with otherwise incurable cholangiocarcinoma (CCA) who are awaiting liver transplantation (LT). The use of endoscopic retrograde cholangiopancreatography (ERCP)-directed photodynamic therapy (PDT) as an alternative to brachytherapy for providing locoregional control in this patient population has not been studied. The aim of this study was to report on our initial experience using ERCP-directed PDT to provide local control in patients with unresectable CCA who were awaiting LT. Patients with unresectable CCA who underwent protocol-driven neoadjuvant chemoradiation and ERCP-directed PDT with the intent of undergoing LT were reviewed. Four patients with confirmed or suspected CCA met the inclusion criteria for protocol LT. All four patients (100%) successfully underwent ERCP-directed PDT. All patients had chemoradiation dose delays, and two patients had recurrent cholangitis despite PDT. None of these patients had progressive locoregional disease or distant metastasis following PDT. All four patients (100%) underwent LT. Intention-to-treat disease-free survival was 75% at mean follow-up of 28.1 months. In summary, ERCP-directed PDT is a reasonably well tolerated and safe procedure that may have benefit by maintaining locoregional tumor control in patients with CCA who are awaiting LT.


Assuntos
Neoplasias dos Ductos Biliares/terapia , Ductos Biliares Intra-Hepáticos/patologia , Quimiorradioterapia , Colangiocarcinoma/terapia , Transplante de Fígado , Terapia Neoadjuvante , Fotoquimioterapia , Adulto , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Prognóstico , Estudos Retrospectivos , Listas de Espera
5.
Am J Transplant ; 13(1): 11-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23136949

RESUMO

Important progress has been made in improving short-term outcomes in solid organ transplantation. However, long-term outcomes have not improved during the last decades. There is a critical need for biomarkers of donor quality, early diagnosis of graft injury and treatment response. MicroRNAs (miRNAs) are a class of small single-stranded noncoding RNAs that function through translational repression of specific target mRNAs. MiRNA expression has been associated with different diseases and physiological conditions. Moreover, miRNAs have been detected in different biological fluids and these circulating miRNAs can distinguish diseased individuals from healthy controls. The noninvasive nature of circulating miRNA detection, their disease specificity and the availability of accurate techniques for detecting and monitoring these molecules has encouraged a pursuit of miRNA biomarker research and the evaluation of specific applications in the transplant field. miRNA expression might develop as excellent biomarkers of allograft injury and function. In this minireview, we summarize the main accomplishments of recently published reports focused on the identification of miRNAs as biomarkers in organ quality, ischemia-reperfusion injury, acute rejection, tolerance and chronic allograft dysfunction emphasizing their mechanistic and clinical potential applications and describing their methodological limitations.


Assuntos
Biomarcadores/sangue , MicroRNAs/sangue , Transplante de Órgãos , Rejeição de Enxerto/sangue , Humanos , Traumatismo por Reperfusão/sangue , Doadores de Tecidos
6.
Am J Transplant ; 13(10): 2703-12, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24010942

RESUMO

The optimal balance between maximizing the number versus the outcome of transplantation utilizing kidneys from small (≤20 kg) pediatric donors remains unclear, complicated by the choice of single versus en bloc transplantation with their attendant technical risks. Using the Organ Procurement and Transplantation Network (OPTN) database, we examined kidney recovery and utilization patterns, and 1-year transplant outcomes by single kilogram weight strata. Between January 1, 2005 and June 30, 2010, 2352 kidneys from ≤20 kg donors were transplanted into 1531 recipients, 710 single kidney transplants (SKTs) and 821 en bloc kidney transplants (EBKTs). Increased donor weight was associated with higher rates of recovery, transplantation and SKT. Low donor weight (linear p < 0.001; quadratic p = 0.003), SKT versus EBKT (p = 0.008), increased cold ischemia time (p = 0.003), local versus nonlocal donor (p = 0.0044), low versus high volume center (p = 0.003) and the interaction term between center volume and donor weight (p = 0.0024) were associated with graft failure. Notably, lower donor weight exacerbated the negative impact of low center volume but did not worsen the negative impact of SKT on outcomes. Our data show that EBKT offers superior 1-year survival at the expense of accomplishing one rather than two transplants. However, SKTs yield excellent outcomes when performed at experienced centers.


Assuntos
Rejeição de Enxerto/diagnóstico , Sobrevivência de Enxerto/fisiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Complicações Pós-Operatórias , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Cadáver , Criança , Pré-Escolar , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Adulto Jovem
7.
Am J Transplant ; 13(3): 729-37, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23312020

RESUMO

Diagnosis and prediction of the severity of hepatitis C virus recurrence (HCVrec) after liver transplantation (LT) remain a challenge. MicroRNAs have been recently recognized as potential disease biomarkers. Archival liver biopsy samples from 43 HCV+ LT recipients were collected at clinical HCVrec time and at 3 years post-LT. Patients were classified as progressors (P = F0/F1) or nonprogressors (NP = F3/F4) according to the severity of fibrosis on the 3-year biopsy. Training (n = 27) and validation (n = 16) sets were defined. RNA was isolated from all biopsies at clinical HCVrec time, labeled and hybridized to miRNA-arrays. Progressors versus nonprogressors were compared using the two-sample t-test. A p-value ≤0.01 was considered significant. The ingenuity pathway analysis tool was used for microRNA and miRNA:mRNA ontology data integration. Nine microRNAs were differentially expressed between groups. A supervised cluster analysis separated samples in two well-defined groups (progressors vs. nonprogressors). Pathway analysis associated those microRNAs with hepatitis, steatosis, fibrosis, cirrhosis and T cell-related immune response. Data integration identified 17 genes from a previous genomic study as 9-microRNAs signature targets. Seven microRNAs were successfully validated in the validation set using QPCR. We have identified a 9-microRNA signature able to identify early post-LT patients at high risk of severe HCVrec during long-term follow-up.


Assuntos
Hepatite C/cirurgia , Cirrose Hepática/diagnóstico , Cirrose Hepática/cirurgia , Transplante de Fígado/efeitos adversos , MicroRNAs/genética , Complicações Pós-Operatórias , Adulto , Idoso , Biomarcadores/análise , Biomarcadores/metabolismo , Progressão da Doença , Feminino , Seguimentos , Perfilação da Expressão Gênica , Rejeição de Enxerto , Sobrevivência de Enxerto , Hepacivirus/patogenicidade , Hepatite C/complicações , Hepatite C/virologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Recidiva , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco
9.
Am J Transplant ; 11(10): 2110-22, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21794090

RESUMO

Despite the advances in immunosuppression, renal allograft attrition over time remains unabated due to chronic allograft dysfunction (CAD) with interstitial fibrosis (IF) and tubular atrophy (TA). We aimed to evaluate microRNA (miRNA) signatures in CAD with IF/TA and appraise correlation with paired urine samples and potential utility in prospective evaluation of graft function. MiRNA signatures were established between CAD with IF/TA versus normal allografts by microarray. Validation of the microarray results and prospective evaluation of urine samples was performed using real-time quantitative-PCR (RT-qPCR). Fifty-six miRNAs were identified in samples with CAD-IF/TA. Five miRNAs were selected for further validation based on array fold change, p-value and in silico predicted mRNA targets. We confirmed the differential expression of these five miRNAs by RT-qPCR using an independent set of samples. Differential expression was detected for miR-142-3p, miR-204, miR-107 and miR-211 (p < 0.001) and miR-32 (p < 0.05). Furthermore, differential expression of miR-142-3p (p < 0.01), miR-204 (p < 0.01) and miR-211 (p < 0.05) was also observed between patient groups in urine samples. A characteristic miRNA signature for IF/TA that correlates with paired urine samples was identified. These results support the potential use of miRNAs as noninvasive markers of IF/TA and for monitoring graft function.


Assuntos
Rejeição de Enxerto , Transplante de Rim , MicroRNAs/genética , Urina , Adulto , Sequência de Bases , Creatinina/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Transplante Homólogo
10.
Transplant Proc ; 51(3): 729-733, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30979457

RESUMO

BACKGROUND: TruGraf v1 is a well-validated DNA microarray-based test that analyzes blood gene expression profiles as an indicator of immune status in kidney transplant recipients with stable renal function. METHODS: In this study, investigators assessed clinical utility of the TruGraf test in patient management. In a retrospective study, simultaneous blood tests and clinical assessments were performed in 192 patients at 7 transplant centers, and in a prospective observational study they were performed in 45 subjects at 5 transplant centers. RESULTS: When queried regarding whether or not the TruGraf test result impacted their decision regarding patient management, in 168 of 192 (87.5%) cases the investigator responded affirmatively. The prospective study indicated that TruGraf results supported physicians' decisions on patient management 87% (39/45) of the time, and in 93% of cases physicians indicated that they would use serial TruGraf testing in future patient management. A total of 21 of 39 (54%) reported results confirmed their decision that no intervention was needed, and 17 of 39 (44%) reported that results specifically informed them that a decision not to perform a surveillance biopsy was correct. CONCLUSIONS: TruGraf is the first and only noninvasive test to be evaluated for clinical utility in determining rejection status of patients with stable renal function and shows promise of providing support for clinical decisions to avoid unnecessary surveillance biopsies with a high degree of confidence. TruGraf is an invaluable addition to the transplant physician's tool kit for managing patient health by avoiding painful and invasive biopsies, reducing health care costs, and enabling frequent assessment of patients with stable renal function to confirm immune quiescence.


Assuntos
Perfilação da Expressão Gênica/métodos , Rejeição de Enxerto/diagnóstico , Transplante de Rim , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Biópsia , Tomada de Decisões , Feminino , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Patologia Molecular/métodos , Médicos , Estudos Prospectivos , Estudos Retrospectivos
11.
Transplant Proc ; 51(3): 722-728, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30979456

RESUMO

TruGraf v1 is a laboratory-developed DNA microarray-based gene expression blood test to enable proactive noninvasive serial assessment of kidney transplant recipients with stable renal function. It has been previously validated in patients identified as Transplant eXcellence (TX: stable serum creatinine, normal biopsy results, indicative of immune quiescence), and not-TX (renal dysfunction and/or rejection on biopsy results). TruGraf v1 is intended for use in subjects with stable renal function to measure the immune status as an alternative to invasive, expensive, and risky surveillance biopsies. MATERIALS AND METHODS: In this study, simultaneous blood tests and clinical assessments were performed in 192 patients from 7 transplant centers to evaluate TruGraf v1. The molecular testing laboratory was blinded to renal function and biopsy results. RESULTS: Overall, TruGraf v1 accuracy (concordance between TruGraf v1 result and clinical and/or histologic assessment) was 74% (142/192), and a result of TX was accurate in 116 of 125 (93%). The negative predictive value for TruGraf v1 was 90%, with a sensitivity 74% and specificity of 73%. Results did not significantly differ in patients with a biopsy-confirmed diagnosis vs those without a biopsy. CONCLUSIONS: TruGraf v1 can potentially support a clinical decision enabling unnecessary surveillance biopsies with high confidence, making it an invaluable addition to the transplant physician's tool kit for managing patients. TruGraf v1 testing can potentially avoid painful and risky invasive biopsies, reduce health care costs, and enable frequent assessment of patients with stable renal function to confirm the presence of immune quiescence in the peripheral blood.


Assuntos
Perfilação da Expressão Gênica/métodos , Rejeição de Enxerto/diagnóstico , Transplante de Rim , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adulto , Biópsia , Feminino , Rejeição de Enxerto/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Transplantados
12.
Transplant Proc ; 39(1): 153-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17275495

RESUMO

The treatment of patients with cirrhosis and hepatocellular carcinoma (HCC) has improved dramatically over the past 10 years. We conducted a 6-year prospective study, using multimodality ablation therapy (MMT) combined with liver transplantation (LTx) for patients with cirrhosis and unresectable HCC. Subjects were classified as: group 1 (n = 35), intention to treat with MMT + LTx; group 2 (n = 16), contemporaneous LTx with "incidental" HCC on explants; group 3 (n = 94), MMT alone; and group 4 (n = 19), palliative care alone. MMT included trans-arterial chemo-embolization (54.4%), trans-arterial chemo-infusion (28.6%), and radio frequency ablation (17%). Group 1, with a mean wait time of 11.6 months pre-MELD era and 5.4 months post-MELD era, had a mean of 2.4 +/- 1.2 MMTs and achieved 1- 3-, and 5-year patient survivals of 100, 100, and 76%, respectively, which was not different from group 2 (incidental HCC), namely 93, 93, and 93%, respectively; or to a contemporaneous non-HCC LTx group: namely 84.3, 78.7, and 73.9%, respectively. Despite careful pretransplant HCC staging, 22.8% (8 of 35) group 1 subjects were understaged. Those subjects in group 1 with true T1-2 stage HCC achieved 100% cancer-free survival at 5 years. Only three cases of HCC recurrence occurred in our series, all of whom were understaged. Our data suggest that pretransplant MMT followed by timely LTx provides excellent disease-free survival at 5 years for patients with true T1-2 stage HCC and cirrhosis. Pretransplant HCC understaging contributes to posttransplant HCC recurrence after LTx.


Assuntos
Carcinoma Hepatocelular/cirurgia , Cirrose Hepática/cirurgia , Transplante de Fígado/patologia , Transplante de Fígado/estatística & dados numéricos , Adulto , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Hepatite B/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
13.
Transplant Proc ; 38(5): 1422-4, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16797321

RESUMO

Portal vein thrombosis (PVT) is considered a relative contraindication to living donor liver transplantation (LDLTx) due to technical difficulty and ethical considerations. So far, there have been a few reported cases of LDLTx with PVT, most of which were treated by thrombectomy with or without a venous conduit. We report a case of LDLTx in an unexpected recipient with grade 4 diffuse PVT, which was successfully managed using a variceal left gastric vein and a deceased donor iliac vein conduit to create a "de novo portal vein" for splanchnic inflow to the right lobe. The patient experienced an uneventful postoperative course with normal blood flow in the de novo portal vein at 1-year follow up. This report demonstrated that a variceal collateral vein can be used as appropriate alternative inflow for the right lobe in LDLTx cases in which an unexpected PVT is encountered.


Assuntos
Doadores Vivos , Nefrectomia/efeitos adversos , Veia Porta/cirurgia , Trombose/cirurgia , Coleta de Tecidos e Órgãos/efeitos adversos , Humanos , Veia Ilíaca/cirurgia , Masculino , Pessoa de Meia-Idade , Terapia de Salvação , Estômago/inervação , Trombose/etiologia , Resultado do Tratamento
14.
Transplant Proc ; 38(5): 1243-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16797273

RESUMO

BACKGROUND: Delayed graft function (DGF) is a problem in kidney transplantation and cold ischemia has been identified as a risk factor. Perfluorocarbons (PFC) have an enhanced ability to dissolve and release oxygen. We evaluated histologically and a number of molecular changes induced by ischemia in stored kidneys with University of Wisconsin (UW) and PFC-based preservation solutions (PFC-UW). MATERIALS AND METHODS: ACI rats were used as kidney donors. UW (control group) or PFC-UW (study group) preservation solutions were used for kidney perfusion. All kidneys were stored at 4 degrees C for 12, 24, and 36 hours. After this time, intragraft histologic evaluation as well as mRNA HO-1 and iNOS levels were also analyzed. RESULTS: In the kidneys stored at 24 hours, mRNA HO-1 levels were elevated in the study group when compared with the control and mRNA iNOS was decreased. CONCLUSION: We observed overexpression of HO-1 and underexpression of iNOS in the kidney tissue stored with PFC-UW solution at 24 hours. These preliminary data suggest that increasing oxygen delivery by PFC added to the perfusion solution triggers cytoprotective mechanism in kidney transplantation.


Assuntos
Fluorocarbonos , Rim , Soluções para Preservação de Órgãos , RNA Mensageiro/genética , Adenosina , Alopurinol , Animais , Biomarcadores , Fluorocarbonos/farmacologia , Regulação da Expressão Gênica , Glutationa , Heme Oxigenase-1/genética , Insulina , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Modelos Animais , Óxido Nítrico Sintase Tipo II/genética , Rafinose , Ratos , Ratos Endogâmicos ACI
15.
Transplant Proc ; 37(5): 2195-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15964377

RESUMO

Hepatic angiosarcoma is a rare malignant vascular tumor that accounts for up to 2% of all primary liver tumors. Accurate diagnosis of this tumor is difficult, especially if the patient has no history of exposure to specific carcinogens including thorotrast, arsenicals, and vinyl chloride monomer. Diagnosis of diffuse angiosarcoma by means of liver biopsy has been reported as treacherous and nondiagnostic. Herein, we present a case of a 61-year-old Caucasian male with history of cryptogenic cirrhosis, normal alpha-fetoprotein, and pretransplant abnormal liver MRI who underwent nondiagnostic liver biopsies followed by liver transplantation. High grade diffuse angiosarcoma was diagnosed in the explanted liver. The patient developed bone metastases at 8 months and is alive 1 year posttransplantation. Diffuse liver tissue infiltration seen pretransplant on CT scan or MRI, suggesting the possibility of diffuse liver lesions (HCC, angiosarcoma, etc) must be fully investigated with all techniques available including multiple open liver biopsies to avoid the sacrifice of a liver allograft in these patients.


Assuntos
Hemangiossarcoma/patologia , Hemangiossarcoma/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
16.
Transplant Proc ; 36(5): 1438-41, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15251353

RESUMO

Most of the few reports about hepatic artery disease found in the literature describe hepatic artery aneurysms or hepatic artery calcifications. Atherosclerosis of the hepatic artery is not commonly evaluated during deceased donor liver procurement. Herein we present a case of a stable 47-year-old Caucasian female donor whose liver function tests were within normal limits and a liver biopsy showed less than 5% steatosis. The liver when received at our center appeared grossly unremarkable. Back-table evaluation showed a complete occlusion of the trunk of the proper hepatic artery. The pathology report revealed hepatic occlusion due to arterial atherosclerosis. Transplantation was canceled, and the liver was used for isolated hepatocyte perfusion, revealing < 25% hepatocyte viability. Hepatic artery atherosclerosis and patency need to be evaluated at the time of procurement to prevent recipient morbidity due to anesthetic induction, or initiation of a recipient abdominal incision prior to declining the liver graft for this rare finding.


Assuntos
Arteriosclerose/patologia , Arteriosclerose/cirurgia , Artéria Hepática/patologia , Artéria Hepática/cirurgia , Transplante de Fígado/métodos , Aorta Abdominal/patologia , Morte Encefálica , Feminino , Hepatectomia/métodos , Humanos , Pessoa de Meia-Idade , Coleta de Tecidos e Órgãos/métodos
17.
Transplant Proc ; 42(7): 2436-46, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20832522

RESUMO

The Organ Procurement and Transplantation Network database (2001-2006) was reviewed for kidney transplant (KT) recipients, to evaluate the effects of use of grafts from donors positive for hepatitis C virus (HCV) on recipient outcome. Data for 76,787 de novo adult KT recipients were included in the analysis. Serologic tests revealed HCV positivity in 6.25% of cadaver kidneys and 2.97% of living-donor kidneys. Median follow-up in patients still alive was 36 months. At multivariable Cox regression analysis in recipients of cadaver kidney, HCV serostatus was significantly associated with overall and graft survival (both P < .001), with a hazard ratio for HCV-positive patients of 1.43 for overall survival and 1.48 for graft survival. Similar results were obtained for living-donor kidney recipients. Recipients of HCV-positive organs tended to be male and African American and to have a shorter waiting time. Infection was the most commonly reported cause of death in recipients of organs from HCV-positive donors. In patients willing to accept HCV-positive grafts (929 [25.6%]), waiting time was significantly shortened (P < .001). However, this benefit was offset by decreased patient survival (P < .001) and graft survival (P = .007).


Assuntos
Hepatite C/complicações , Transplante de Rim/fisiologia , Doadores de Tecidos , Adolescente , Adulto , Idoso , Cadáver , Bases de Dados como Assunto , Humanos , Transplante de Rim/métodos , Transplante de Rim/mortalidade , Tempo de Internação , Doadores Vivos , Pessoa de Meia-Idade , Análise de Regressão , Estudos Retrospectivos , Fatores de Tempo , Listas de Espera
18.
Clin Transplant ; 16 Suppl 7: 6-14, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12372038

RESUMO

BACKGROUND: The Th1-Th2 paradigm proposes clonal expansion of Th2 lymphocytes as the basis of allograft tolerance. The Th2 cells have been found to be present in recipients with long-term allograft survival. However, the presence of Th2 cells and tolerance is not a uniform finding. Previously we have shown that pre-engraftment single dose rapamycin and a 7-d course of cyclosporin induce transplantation tolerance to 120 d. In the present study, we investigated the immunobiology of grafts in a long-term follow-up (>350 d). METHODS: Kidney allografts (n = 7), isografts (n = 5) and single nephrectomy (n = 3) groups were followed for 350 +/- 87 d. Heterotopic kidney transplant was performed by the same surgeon in the allograft group (ACI-Lewis) and the isograft group (Lewis-Lewis). The left kidney was removed in the single nephrectomy group. The allograft group was treated with pre-engraftment single dose rapamycin and a 7-d course of cyclosporin. A kidney biopsy was performed at midpoint time for histological study and tissue was frozen for measuring intragraft cytokine expression (IL-4, IL-10) in all animals. Prior to biopsy, serum blood urea nitrogen (BUN) and creatinine (Cr) levels were studied. Serum BUN, Cr levels, plus 24-h urinary protein (PRO) were measured prior to sacrifice. Randomly, four allograft rats received skin grafts (ACI, Lewis and Buffalo skin donors) after kidney biopsy. Skin grafts were studied for a mean of 6 weeks for signs of acceptance or rejection. Analysis of variance (ANOVA) with Tukey's test was used; p < 0.05 was considered statistically significant. RESULTS: The mean follow up was 352 +/- 87 d. BUN and Cr levels at biopsy time (mean 214 d) were not statistically different between the three groups (p = 0.19 and p = 0.66). At sacrifice (mean 352 d), BUN, Cr and PRO were statistically different between allograft and isograft groups (p = 0.013), and between allograft and single nephrectomy groups (p = 0.027). Functional and histological signs of graft loss occurred in three of seven (42.8%) of the allografts at 352 d. Using BANFF criteria, three allografts at biopsy time and seven allografts (100%) and four isografts (80%) at sacrifice time developed chronic histologic changes. Intragraft overexpression of IL-4 and IL-10 was seen at biopsy and sacrifice time in six of seven allografts and one of five isografts. All donor specific skin grafts (ACI-Lewis) on allografts were accepted and third party (Buffalo) donor skin grafts were rejected in all animals (>95% skin necrosis). CONCLUSIONS: This highly stringent, functional, renal transplant model yields 100% normal renal function as compared with isografts at 120 d follow-up. With the follow-up extended to 350 d, 43% of the allografts loose function and develop a chronic allograft histology despite a demonstrated intragraft Th2 cytokine dominance and donor specific skin graft acceptance.


Assuntos
Transplante de Rim/fisiologia , Modelos Animais , Tolerância ao Transplante/imunologia , Transplante Heterotópico/fisiologia , Animais , Citocinas/metabolismo , Rejeição de Enxerto/imunologia , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Rim/patologia , Transplante de Rim/imunologia , Masculino , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos Lew , Linfócitos T/imunologia , Transplante Heterotópico/imunologia , Transplante Homólogo , Transplante Isogênico
19.
Am J Transplant ; 3(3): 312-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12614287

RESUMO

We investigated the efficacy of nonresective ablation techniques and the tumor-free survival of cirrhotic patients undergoing liver transplantation for hepatocellular carcinoma (HCC). In group 1, 11 HCC patients were treated with these techniques and transplanted. On the waiting list, patients were treated to complete ablation, judged by gadolinium-enhanced MRI and alpha-fetoprotein (AFP) levels. Group 1 was compared with a concurrent group of 10 liver transplant patients (group 2) with incidental HCC (stages T1 three patients, T2 seven patients). The group 1 patients received 36 procedures (4 alcohol ablations, 14 trans -hepatic artery chemo-embolizations, 15 trans -hepatic chemo-infusions, and 3 radio frequency ablations) for treatment of 13 liver masses. Tumor-node-metastasis (TNM) stage was reduced in eight patients (72.7%), unchanged in two patients and increased in one patient before transplantation. The mean waiting time for transplantation was 12.9 7.6 months. Both groups had a tumor-free survival of 100%, at 30 12 months post transplant. On pathology, 54.5% of explanted livers had residual viable HCC after tumor treatment, and 36.4% (4/11) explants had synchronous lesions. Non-resective ablation therapy is safe and effective in reducing the HCC progression in cirrhotic patients awaiting liver transplantation. The cancer-free survival rate in this treatment group is equal to that for incidental T1-T2 HCCs.


Assuntos
Carcinoma Hepatocelular/terapia , Fibrose/terapia , Neoplasias Hepáticas/terapia , Transplante de Fígado/métodos , Adulto , Carcinoma Hepatocelular/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
20.
Clin Transplant ; 18(5): 502-12, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15344951

RESUMO

BACKGROUND: Orthotopic liver transplantation (OLT) for patients with small hepatocellular carcinoma (HCC) is widely accepted, and the usefulness of local ablation techniques as a bridge for liver transplantation is still under investigation. METHODS: From December 1997 to February 2003, patients with cirrhosis and T0-T1-T2-T3 stage HCC received multi-modality ablative therapy (MMT) for the treatment of their HCC and were evaluated for OLT; listed, and transplanted when an allograft became available. MMT included radiofrequency ablation (RFA), and/or Trans-Arterial Chemo-Embolization (TACE), and alcohol (EtOH) ablation, followed by Trans-Arterial Chemo-Infusion (TACI), with repeated treatments based on follow up hepatic magnetic resonance imaging (MRI) during the waiting period for OLT. RESULTS: A total of 135 HCC patients were seen at our center within this time frame. The intention-to-treat group included 33 (24.4%) patients with T0, T1, T2, T3 HCC and cirrhosis. There were 31 men and two women. The mean age was 53.6 +/- 7.2 yr. All patients received MMT with a mean of 2.90 +/- 1.5 procedures per patient. Tumor-node-metastasis (TNM) stages at time of listing were: T0 in one patient, T1 in nine patients, T2 in 17 patients, and T3 in six patients. Twenty-eight (85%) patients have received OLT. Five (12.19%) patients were listed and removed (dropout) from the transplant waiting list after waiting 5, 5, 5, 8, and 14 months respectively. The waiting time of the HCC listed group was 9.1 +/- 14.8 months with a mean follow up of 32 months. OLT patient survival and cancer-free survival are 92.9% and 95.24%, respectively; the overall survival of intention-to-treat group was 79% at 32 months follow up. Predictors of dropout included an alpha-fetoprotein (AFP, >400 ng/mL) and T3 HCC stage. CONCLUSION: Aggressive ablation therapy with a short transplant waiting time optimizes the use of OLT for curative intent in selective cirrhotic HCC patients.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Pacientes Desistentes do Tratamento , Listas de Espera , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/terapia , Ablação por Cateter , Quimioembolização Terapêutica , Terapia Combinada , Intervalo Livre de Doença , Etanol/administração & dosagem , Óleo Etiodado/administração & dosagem , Feminino , Seguimentos , Humanos , Cirrose Hepática/cirurgia , Cirrose Hepática/terapia , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
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