摘要:

Members of the Clinical Practice Committee, American Society of Transplantation, have attempted to define referral criteria for solid organ transplantation. Work done by the Clinical Practice Committee does not represent the official position of the American Society of Transplantation. Recipients for solid organ transplantation are growing in numbers, progressively outstripping the availability of organ donors. As there may be discrepancies in referral practice and, therefore, inequity may exist in terms of access to transplantation, there needs to be uniformity about who should be referred to transplant centers so the system is fair for all patients. A review of the literature that is both generic and organ specific has been conducted so referring physicians can understand the criteria that make the patient a suitable potential transplant candidate. The psychosocial milieu that needs to be addressed is part of the transplant evaluation. Early intervention and evaluation appear to play a positive role in maximizing quality of life for the transplant recipient. There is evidence, especially in nephrology, that the majority of patients with progressive failure are referred to transplant centers at a late stage of disease. Evidence-based medicine forms the basis for medical decision-making about accepting the patient as a transplant candidate. The exact criteria for each organ are detailed.These guidelines reflect consensus opinions, synthesized by the authors after extensive literature review and reflecting the experience at their major transplant centers. These guidelines can be distributed by transplant centers to referring physicians, to aid them in understanding who is potentially an acceptable candidate for transplantation. The more familiar physicians are with the exact criteria for specific organ transplantation, the more likely they are to refer patients at an appropriate stage. Individual transplant centers will make final decisions on acceptability for transplantation based on specific patient factors. It is hoped that this overview will assist insurers/payors in reimbursing transplant centers for solid organ transplantation, based on criteria for acceptability by the transplant community. The selection and management of patients with end-stage organ failure are constantly changing, and future advances may make obsolete some of the criteria mentioned in the guidelines. Most importantly, these are intended to be guidelines, not rules.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.The majority of liver transplant centers require a 6-month abstinence period before listing candidates for liver transplantation with alcoholic cirrhosis and a persistent sobriety thereafter. We attempted to identify risk factors for failure to comply with these requirements.Methods.Ninety-nine consecutive patients with alcoholic cirrhosis were referred for liver transplant evaluation between September 1996 and May 1998. The mean age was 49 years, 74% were male, and 54% were hepatitis C virus positive. To be listed, patients had to meet the following requirements. All patients received extensive psychosocial evaluations and were frequently monitored with random urine and blood alcohol tests; patients found positive were excluded or removed from the liver transplant waiting list. Detailed patient information was entered into a computerized database, and 36 discreet variables were analyzed in relation to success (patient listed and remained on the list) or failure (not listed or removed from the list based on noncompliance).Results.Forty-nine patients were successfully listed. Nineteen received a transplant, with a 95% 1-year patient and graft survival rate and 21% alcohol relapse rate after transplantation. Twenty-two patients had either medical contraindication and/or died before transplant listing. Twenty-four patients were never listed and four were removed from the list due to recurrent alcoholism, for a total of 28 failures. Our statistical analysis identified five significant risk factors for failure: (I) living arrangement (alone/family versus community/friend),P=0.006; (II) history of suicide ideation,P=0.03; (III) history of previous alcohol-related hospitalization,P=0.01; (IV) lack of previous alcoholic rehabilitation before transplant evaluation,P=0.001; and (V) failure to accept further alcoholic rehabilitation before orthotopic liver transplantation,P=0.01.Conclusions.Our experience confirms that transplantation can be extremely successful in properly selected patients with alcoholic cirrhosis. We identified several predictive psychosocial factors of early alcoholic recidivism in transplant candidates.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Modification of a donor cornea by gene therapy ex vivo has potential to modulate irreversible rejection, the major cause of corneal graft failure. Our aim was to transfer the gene encoding mammalian IL-10 to ovine donor corneas and to determine subsequent orthotopic corneal allograft survival in an outbred sheep model.Methods.The replicative capacity of ovine corneal endothelium was determined by autoradiography after deliberate injury. A replication-defective adenovirus was used to deliver the lacZ reporter gene to ovine corneas and transfected corneas were organ-cultured in vitro to allow transfection efficiency, duration of reporter gene expression, and toxicity attributable to the vector to be determined. A cDNA encoding full-length ovine IL-10 was cloned into an adenoviral vector that was used to transfect donor corneas ex vivo before transplantation. Orthotopic penetrating corneal transplantation was performed in outbred sheep.Results.Sheep corneal endothelium was found to be essentially amitotic. Transfection of >70% corneal endothelial cells was achieved with the viral vector and expression was maintained for 28 days in vitro. IL-10 mRNA was detectable in transfected, organ-cultured corneas for 21 days in vitro. Donor corneas transfected with cDNA encoding IL-10 showed significantly prolonged survival after penetrating keratoplasty (median 55 days, range 19 ⩾300 days) compared with control corneas (median 20.5 days, range 18–32 days,P=0.011).Conclusion.Local gene therapy-mediated expression of the immunomodulatory cytokine IL-10 has the potential to reduce the incidence of corneal graft rejection and to prolong corneal allograft survival.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Aim.The effect of fatty liver on graft survival, especially with reference to macrovesicular and microvesicular steatosis, is still uncertain. This preliminarily study was designed to create a noninvasive method for the quantification of the hepatic fat content in vivo and to establish provisional criteria for the assessment of fatty donor livers before liver transplantation among transplant surgeons, radiologists, and pathologists.Methods and Materials.Different degrees of rat fatty liver model were established by feeding rats a diet deficient in choline and methionine for different periods of time. Computed tomography (CT) with test tubes containing variable percentages of fat equivalent substance were used to assess the severity of fatty change of the rat liver. This was then correlated with the histological classification, level of hepatic enzymes, and graft survival.Results.Linear correlation between the fat volume fraction added to the test tubes and CT density were found. The process of producing a fatty liver via diet alteration peaked at week 3. At this time hepatic enzymes, radiological fat content, and posttransplantation survival were worse (P=0.013), compared with other time points. Radiological assessment of fatty liver correlated well with survival and serum glutamic oxaloacetic transaminase and glutamic pyruvate transaminase levels.Conclusion.Severe microvesicular steatosis does not influence recipient survival, however, macrovesicular steatosis affects graft survival. Caliber CT is a practical and simple method that allows an accurate noninvasive quantitative assessment of hepatic fatty infiltration. It has potential to be a useful parameter for the assessment of donor livers for clinical liver transplantation.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.Hepatocyte transplantation using polymeric matrices is under investigation as an alternative therapy for metabolic liver diseases. Long-term engraftment of hepatocytes in polymers has been demonstrated. However, the metabolic activity of hepatocytes in such devices has never been assessed in direct comparison with liver grafts.Methods.Hepatocyte and partial liver transplantation were evaluated in the scurvy-prone osteogenic disorder Shionogi rat model. Biodegradable poly glycolic acid matrices seeded with hepatocytes equivalent to 20% of the recipient’s liver mass, or 20% liver grafts were heterotopically transplanted into ascorbic acid- (AsA) deficient recipients. Recipients of cell-free matrices or AsA-deficient liver grafts served as controls. Recipients were set on AsA-free diet after transplantation. Plasma AsA levels, AsA concentrations in liver and adrenal gland tissue, and body weight ratios were assessed and H&E histology was performed.Results.Recipients from the control groups showed symptoms of scurvy at 1 month after cessation of AsA supply. Hepatocyte transplantation and auxiliary liver transplantation prevented symptoms of scurvy and increased plasma and tissue AsA levels and body weight ratios. AsA levels in recipients of 20% liver grafts were comparable to normal control animals.Conclusions.Hepatocytes transplanted in polymeric matrices are able to compensate for liver-based metabolic deficiencies. Hepatocyte transplantation improves plasma AsA levels in AsA-deficient recipients. However, auxiliary liver grafts are superior to hepatocyte grafts in improving metabolic parameters. Further research work is needed to increase the efficiency of liver cell transplantation with regard to a clinical application.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.The aim of the present study was to evaluate hepatic content of adenine nucleotides and their degradation products in non-heart-beating donor (NHBD) pigs and its relationship with recipient survival.Methods.Thirty animals were transplanted with an allograft from NHBDs. After warm ischemia (WI) time (20, 30, or 40 min), cardiopulmonary bypass and normothermic recirculation (NR) were run for 30 min. Afterward, the animals were cooled to 15°C and liver procurement was performed.Results.Survival rate was 100% in the 20WI, 70% in the 30WI, and 50% in the 40WI. Livers from non-surviving animals had higher levels of xanthine after NR than livers from surviving animals. Logistic regression analysis revealed that xanthine at the end of NR was the only variable able to predict survival with a calculated sensitivity of 80% and a specificity of 60%. Prolongation of warm ischemic period leaded to a greater xanthine accumulation as well as increased plasma &agr;-glutathione S-transferase levels at reperfusion. Xanthine at NR and &agr;-glutathione S-transferase at reperfusion significantly correlated, indicating that donor xanthine contributes to some extent to the severity of the lesion by ischemia-reperfusion.Conclusions.It is suggested that xanthine content in the donor is able to predict survival after transplantation. Xanthine is significantly involved in the hepatic lesion elicited by warm ischemia and subsequent ischemia-reperfusion associated to liver transplantation from a NHBD.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Background.The combined application of exogenous surfactant and inhaled nitric oxide was evaluated for prevention of ischemia-reperfusion injury of the lung.Methods.Left lungs were selectively perfused in 18 minipigs in situ with cold preservation solution. After 90 min of warm ischemia, the lungs were reperfused and the right pulmonary artery and bronchus were ligated (control group, n=6). Exogenous surfactant was instilled via bronchoscopy during ischemia (surfactant group, n=6). In a third group, surfactant was applied, followed by administration of inhaled nitric oxide (surfactant+NO group, n=6). Hemodynamic and respiratory parameters were recorded for 7 hr, and bronchoalveolar lavage fluid (BALF) was obtained before and after reperfusion for measurement of surface tension, small aggregate/large aggregate ratio, protein and phospholipid contents, and a differential cell count.Results.Control group animals survived for 3.7±1.4 hr. In both surfactant-treated groups, five out of six animals survived the observation period (P<0.001). Dynamic compliance of the lung was decreased in control animals (P<0.001). In the surfactant+NO group, arterial PO2was higher than in both other groups (P<0.001). BALF cell count and histology showed reduced neutrophil infiltration in surfactant+NO-treated lungs. Surface tension assessed in BALF with a pulsating bubble surfactometer was severely impaired in control animals (&ggr;min, 14.82±9.95 mN/m), but maintained in surfactant-treated (&ggr;min, 1.11±0.56 mN/m) and surfactant+NO-treated animals (&ggr;min, 3.90±2.35 mN/m,P=0.02).Conclusions.Administration of exogenous surfactant in lung reperfusion injury results in improved lung compliance. The addition of inhaled NO improves arterial oxygenation and reduces neutrophil extravasation compared with surfactant treatment alone.

ISSN:0041-1337    

出版商:OVID    

年代:2001

数据来源: OVID