Variations in cardiac transplantation: comparisons between the United Kingdom and the United States.

BACKGROUND: International practice variations have been documented in various health care specialties. This study compares cardiac transplantation in the UK with practice in the US. METHODS: UK data were from an ongoing multi-center prospective study, the UK Cardiothoracic Transplant Audit. The UK population comprised 620 listings and 463 transplants. US data were obtained from UNOS and comprised 3946 listings and 4704 transplants. RESULTS: There was a mean of 14 transplants per center per year in the US compared with 34 in the UK. Notable differences in practice include rarity of listing in the UK of patients > 65 years (0.2% vs 4.1% in US) and patients with previous transplants (UK 0.9%, US 3.2%). Patients listed in the US were more likely to be on ventricular assist devices (odds ratio 8.0, 95% CI 3.0-21.7) or inotropes (odds ratio 4.9, 95% CI 3.7-6.4). Living donor (domino) transplants, although comprising 7% of transplants in the UK, are virtually non-existent in the US (1 domino in 4704 transplants). Heterotopic transplants were more common in the UK (4.4% vs 0.5%). Indications for transplant were similar (except retransplantation). The donor age was > 35 years in 43% of UK donors vs 33% of US donors. CONCLUSION: This study reveals substantial practice differences between the UK and US. Further studies are required to examine the reasons for these practice differences, the influence on transplant outcome, and their ethical and economic implications.     

A report on the activity and clinical outcomes of renal non-heart beating donor transplantation in the United Kingdom

The use of kidneys from non-heart beating donors (NHBDs) presents a paradox; whilst they provide more organs for transplantation, there is an increased risk of poor graft outcome, particularly in the short term. This study has highlighted the difference in early graft function and late graft survival between NHBD kidneys with short (controlled) and long (uncontrolled) warm ischaemic times. Whilst it would seem that it is preferable to use controlled donors only, their numbers are small. By employing a rational approach to the use of each of these types of kidney, such as structured viability assessment and risk analysis, it may be that the results of uncontrolled NHBD can be improved.     

Adult orthotopic liver transplantation in the United Kingdom and Ireland between 1994 and 2005

BACKGROUND: The UK and Ireland Liver Transplant Audit collects information on all liver transplantations that are carried out in both countries. In this paper, we describe these transplantations and their outcomes in adult patients according to primary liver disease diagnosis, type of transplantation and period. METHODS: A prospective cohort study of 7906 orthotopic liver transplantations carried out between April 1994 and June 2005 in the United Kingdom and Ireland. Multivariable logistic regression was used to investigate improvements in mortality according to period of transplantation adjusted for recipient and donor characteristics. RESULTS: A total of 6,850 transplantations were done in adults (patients 16 years or older). Of these, 836 (12.2%) were first super-urgent procedures (33.7% men; median age 36 years), and 5,072 (74.0%) first elective procedures (60.0% men; median age 52 years). The percentage of patients who received a donor organ with abnormal appearance gradually increased, especially in patients receiving an elective transplant. Mortality at 90 days after first super-urgent transplant decreased from 29.6% (95% confidence interval: 23.5% to 36.9%) before October 1, 1996 to 16.0% (11.7% to 21.7%) after October 1, 2002. Considering the same time periods, mortality at 90 days after first elective transplant decreased from 10.6% (8.9% to 12.7%) to 7.7% (6.3% to 9.3%). Multivariable analysis demonstrated that these improvements cannot be explained by changes in the risk profile of recipients and donors. CONCLUSIONS: Patients undergoing a liver transplantation in the most recent years had a better survival than patients with similar characteristics transplanted 10 years earlier. Posttransplant survival has improved despite a deteriorating quality of donor organs.     

Split liver transplantation is utilized infrequently and concentrated at few transplant centers in the United States

Split liver transplantation (SLT) is 1 strategy for maximizing the number of deceased donor liver transplants. Recent reports suggest that utilization of SLT in the United States remains low. We examined deceased donor offers that were ultimately split between 2010 and 2014. SLTs were categorized as “primary” and “secondary” transplants. We analyzed allocation patterns and used logistic regression to evaluate factors associated with secondary split discard. Four hundred eighteen livers were split: 54% from adult, 46% from pediatric donors. Of the 227 adult donor livers split, 61% met United Network for Organ Sharing “optimal” split criteria. A total of 770 recipients (418 primary and 352 secondary) were transplanted, indicating 16% discard. Ninety‐two percent of the 418 primary recipients were children, and 47% were accepted on the first offer. Eighty‐seven percent of the 352 secondary recipients were adults, and 7% were accepted on the first offer. Of the 352 pairs, 99% were transplanted in the same region, 36% at the same center. In logistic regression, shorter donor height was associated with secondary discard (odds ratio 0.97 per cm, 95% CI 0.94‐1.00, P = .02). SLT volume by center was not predictive of secondary discard. Current policy proposals that incentivize SLT in the United States could increase the number of transplants to children and adults.     

骨髓移植供体选择的研究

为了保证异基因骨髓移植成功，本文自１９８１年至１９９０年对拟接受骨髓移植的１８４例患者及其家属共５４１人进行了ＨＬＡ配型。患者与供体相合率为４６．８％，高于理论值并分析了偏高的原因。此外，对血清学与细胞学配型相关性和供、受者间ＨＬＡ相合程度以及不同血缘关系等进行了探讨。根据患者的不同病程、供体人数的多少、不同质量的ＨＬＡ抗血清等方面总结出一套较好的ＨＬＡ分型方法，为骨髓移植患者选择了理想供体。     

Geographic disparities in access to organ transplantation in the United Kingdom

In the United Kingdom, geographic variations in access to transplantation seem to exist-median waiting time to transplantation ranges between 305 and 1,236 days for kidney recipients, 36 and 73 days for liver recipients, and 66 and 667 days for heart recipients (although this latter example must be interpreted with caution). These variations may result from a number of factors. Different patterns of end-stage organ disease are particularly relevant for patients with kidney failure. Protocols for transplant assessment are now available and may reduce inequality. Regional variations in donation rates also exist but are poorly understood.     

Renal transplantation in the United Kingdom for patients from ethnic minorities

BACKGROUND: To investigate any differences in access to transplant and post-transplant outcomes for ethnic minority patients in the United Kingdom, national data on ethnicity of patients on the waiting list, those receiving a transplant, and deceased donors were analyzed. METHODS: Adult patients and donors were included. Ethnic origin was classified as white, Asian, black, or "other." National data were analyzed, and 2001 U.K. National census data were used for comparative purposes. Median waiting times to transplant were obtained from Kaplan-Meier estimates for patients registered 1998-2000. Transplant survival was estimated for patients transplanted from 1998 to 2003. RESULTS: A total of 92% of the U.K. population was white, compared with 77% of waiting list patients, 88% of transplant recipients, and 97% of deceased donors. Median waiting time to transplantation for white patients was 719 days (95% confidence interval 680-758) compared with 1368 (1131-1605) days for Asian patients and 1419 (1165-1673) days for black patients. The degree of human leukocyte antigen matching achieved was inferior for Asian and black patients. There is some evidence of inferior 3-year transplant survival for black patients compared with white and Asian patients (P=0.03). CONCLUSIONS: There are imbalances in the ethnic make up of the waiting list, the donor pool, and renal transplant recipients. There are significant differences in both post-transplant outcomes and time to transplantation between patients of different ethnic origin. Waiting times are influenced by allocation schemes, and the 2006 U.K. National Kidney Allocation Scheme is designed to achieve greater equity of access to transplant for all patients, regardless of geography, blood group, or ethnicity.     

The variation among transplant center results in the United Kingdom and Ireland from 1977 to 1981

An analysis of pooled data from transplants performed between 1977 and 1981 in 29 centers throughout the United Kingdom and Ireland revealed that the pattern of loss varied according to cause and postoperative time. Loss from rejection was characterized by a bimodal pattern in which early (0-25 days) and late (26-100 days) peaks of rejection were distinguishable. Rejected second transplants exhibited this phenomenon more than first transplants, and the loss was proportionately greater during the early period, suggesting that prior sensitization played an important role. Graft loss from technical causes and recipient death showed distinctly different patterns of loss. These findings suggested that, when possible, transplant survival statistics should be analyzed separately according to postoperative time and cause of loss. In applying these preliminary observations of the pooled data to a comparative study of the results in the different centers it was noted that such comparisons could be substantially affected by random variability in estimates of actuarial survival rates. Therefore, a simple method of ranking was developed in which centers were allocated to high or low survivorship categories, or to an indeterminate category when the standard error in estimated actuarial survival was relatively large. Whereas the variation in loss rate from death with a functioning transplant (DWFT) was found to be indistinguishable from random variability, both nonimmunological failure (NIF) and immunological failure (IF) of the graft were found to be legitimate bases for ranking. Furthermore, center ranking based on IF at 0-25 days failed to exhibit a significant relationship with IF at 26-100 days, which could indicate important center differences associated with antirejection treatments during these two periods. These results showed that, ideally, time-cause parameters should be analyzed separately when comparing transplant survival statistics in different centers.     

Variations in the assessment practice for renal transplantation across the United Kingdom

BACKGROUND: To investigate whether there are any variations in the evaluation of adult candidates for cadaveric renal transplantation among transplant centers in the United Kingdom. METHODS: An online survey of transplant units in the United Kingdom, including nephrologists, surgeons, and transplant coordinators, measured differences in the assessment process and evaluation of patient's age, body mass index (BMI), cardiovascular comorbidity, and viral serology. RESULTS: A response was received from 20 out of the 23 centers (87%). These centers perform 90% of all renal transplants in the United Kingdom. In 30% of the units, there is no formal transplant assessment clinic. There is no cutoff age limit for assessment across the United Kingdom, but 12 centers (60%) exclude patients with a high BMI, with a median cutoff BMI of 35. Eight out of the 20 centers do not give cytomegalovirus (CMV)-negative patients the option to receive kidneys from a CMV-positive donor. Hepatitis C antibody-positive donors are not used in 50% of the units. There is considerable variation in the investigation of cardiovascular disease and exclusion criteria based on cardiovascular status of the patients. Five units have no consistent policy of re-evaluating patients once they are listed. CONCLUSIONS: There is evidence, from this study, of significant variations in the assessment of patients for renal transplantation across the United Kingdom. Further research and better-defined guidelines are required for a uniform assessment process and to ensure equity of access to the renal transplant waiting list.     

Policy variation in donor and recipient status in 11 pediatric renal transplantation centers

Background

Evidence-based guidelines for pediatric renal transplantation (Tx) are lacking. This may lead to unwanted treatment variations. We aimed to quantify the variation in treatment policies and its consequences in daily practice in 11 centers that provide renal Tx for children in three European countries.

Methods

We surveyed Tx policies in all ten centers in the Netherlands and Belgium and one center in Germany. We compared Tx policies with the therapies actually provided and with recommendations from available published guidelines and existing literature. Information on treatment policies was obtained by a questionnaire; information on care actually provided was registered prospectively from 2007 to 2011. The clinical guidelines were identified by searches of MEDLINE and websites of pediatric nephrology organizations.

Results

Between centers, we found discrepancies in policies on: the minimum accepted recipient weight (8–12 kg), the maximum living and deceased donor age (50–75 and 45–60 years, respectively). HLA-match policies varied between acceptation of all mismatches to at least 1A1B1DR match donor transplantations amounting to 49 % in the Netherlands versus 26 % in Belgium (p?=?0.006).

Conclusions

Management policies for renal Tx in children vary considerably between centers and nations. This has a direct impact on the delivered care, and by extrapolation, on health outcome.     

供体骨髓输注发生嵌合体与肾移植急性排斥反应的关系

目的：探讨供体骨髓输注发生嵌合体与肾移植急性排斥反应的关系及其临床意义.方法：将供体为男性的女性尸体肾移植患者55例,分为术前未行供体骨髓输注者30例（未输注组）;术前行供体骨髓输注的肾移植25例（输注组）.自末梢血中提取DNA,利用nested PCR法检测Y染色体上的特异基因片断DYZ-1.结果：证实有微嵌合发生共32例中13例（40.6%）、23例无嵌合体存的病例中有10例（43.5%）,都发生过1次或1次以上的急性排斥反应,两组之间比较差异无统计学意义;输注组中当微嵌合现象消失、PCR检测转为阴性时,未见排斥反应病例发生.结论：供体骨髓输注有利于促进微嵌合的形成,嵌合体的消失现象与急性排斥反应之间无相关关系,不能以此作为诊断急性排斥反应的依据.     

An economic evaluation of pediatric small bowel transplantation in the United Kingdom

BACKGROUND: Small bowel transplantation (SBTx) offers an alternative to parenteral nutrition (PN) for the treatment of chronic intestinal failure in children: this study estimated its cost-effectiveness in the early phase of a U.K. program. METHODS: Children assessed for SBTx were categorized as: 1) requiring SBTx following PN-related complications (n=23), 2) stable at home not requiring SBTx (n=24), and 3) terminally ill and unsuitable for SBTx (n=6). Costs were estimated from detailed resource-use data. Two comparisons were used for effectiveness: actual survival following transplantation (n=14) compared to: 1) estimated survival without transplantation using a prognostic model, and 2) the waiting list experiences of all patients listed for SBTx (n=23). RESULTS: Mean costs up to 30 months were pounds sterling 207,000 for those transplanted or on the waiting list, pounds sterling 159,000 for those stable on home PN, and pounds sterling 56,000 for those terminally ill. The prognostic model estimated a mean survival gain from transplantation of 0.12 years over 30 months, and suggested that transplantation was cost-saving. The second approach suggested that transplantation reduced survival by 0.24 years at an additional cost of pounds sterling 131,000. CONCLUSIONS: Firm conclusions on cost-effectiveness of SBTx are not possible given the two different estimates. The prognostic model approach (suggesting that pediatric SBTx may provide a small survival benefit at a small reduction in costs) should be less subject to bias, but the model requires external validation. Meanwhile, children at risk of fatal PN-complications should be given the opportunity to receive a SBTx only within a continuing formal assessment of the technology.