Pregnancy after organ transplantation: a report from the UK Transplant pregnancy registry.

BACKGROUND: Maternal and fetal complications in pregnancies after renal transplantation have been highlighted in several reports, but information on their main predisposing factors is limited. The U.K. Transplant Pregnancy Registry was established in 1997 to obtain detailed information on pregnancies in female organ transplant recipients across the U.K. METHODS: For each female kidney, liver, or cardiothoracic organ transplant recipient who had had a recent pregnancy, data on maternal and fetal factors and pregnancy outcomes were collected using forms completed by their transplant follow-up and obstetric units. For kidney transplant recipients, the factors that influence pregnancy outcome were studied using logistic regression, and the effect of pregnancy on graft function was analyzed. RESULTS: There were live births in 83%, 69%, and 79% of pregnancies in cardiothoracic organ, liver, and kidney recipients, respectively. In 50% of live births from renal patients, delivery was preterm (<37 weeks), with 83% of the preterm infants delivered via caesarean. Preterm delivery was associated with maternal drug-treated hypertension and impaired renal function. A matched case-control study showed no evidence of increased renal allograft loss after pregnancy. A univariate survival analysis, however, suggested an association between drug-treated hypertension during pregnancy and poorer postpregnancy graft survival. In patients with prepregnancy serum creatinine (SCr) >150 micromol/L, a trend toward increased postpregnancy SCr was identified. CONCLUSIONS: Pregnancy is likely to end in a live birth in a majority of organ transplant recipients. In patients with greater prepregnancy SCr and/or drug-treated hypertension during pregnancy, however, subsequent renal function may be adversely affected.

Long-term graft outcome with mycophenolate mofetil and azathioprine: A paired kidney analysis.

BACKGROUND: Randomized controlled trials and U.S. Registry data have demonstrated that mycophenolate mofetil (MMF) reduces acute rejection rates and improves graft survival. We undertook the first paired kidney analysis comparing the effects of MMF and azathioprine on graft outcome in the United Kingdom. METHODS: In all, 238 deceased donors from 1999 to 2002 who donated one kidney to a patient treated with MMF and the other kidney to a patient treated with azathioprine were identified from the national transplant database held by U.K. Transplant. Graft function and rates of change of graft function were compared using multiple linear regression analyses adjusting for covariates on an intention-to-treat basis. Incidence of acute rejection and delayed graft function were studied using logistic regression. Patient and graft survival censored for death were evaluated with Cox regression analyses. RESULTS: The MMF-treated patients exhibited a nonsignificant trend towards improved graft function but with increased rejection rates (44% versus 31%, P < 0.01). Treatment with MMF did not reduce delayed graft function rates. Univariate analysis showed that graft survival was inferior in MMF-treated patients (90% versus 95%, log-rank, P = 0.02) but in multivariate Cox regression models, MMF treatment was not a significant factor. Surprisingly, in the first year 32% of patients achieved daily doses of less than 2 g of MMF compared to 18% of patients who received less than 100 mg of azathioprine (P < 0.01). CONCLUSION: In this real-life study, there was no difference in patient or graft outcome between MMF and azathioprine treated groups despite increased rejection rates in patients receiving MMF therapy.

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.

How to increase organ donation: does opting out have a role?

Every country needs to increase the number of deceased organ donors and the potential impact of a change to opting-out legislation remains unproven, despite the apparent association between opting out and higher donor rates. However, the Spanish model--so successful in Spain and many other countries--is not based on a requirement for opting out, and, in the UK, deceased organ donation has increased by 25% in 3 years through implementation of a series of recommendations that have transformed the infrastructure of donation. A major review of opting out concluded that it is not appropriate for the UK at this time.

Impact of the 1998 UK National Allocation Scheme for deceased heartbeating donor kidneys.

INTRODUCTION: National and regional strategies for allocating deceased heartbeating (DHB) donor kidneys to patients awaiting transplant are of great importance and have major implications for patients and healthcare systems. We describe the rationale for the 1998 National Kidney Allocation Scheme (1998 NKAS) and its impact on renal transplantation in the United Kingdom over 5 years. METHODS: The 1998 NKAS was based on three tiers of patients defined by human leukocyte antigen (HLA) mismatch. This involved national allocation of well-matched kidneys in tiers 1 and 2, with regional allocation for less well-matched patients in tier 3. Pediatric patients (younger than 18 years) and regional patients were prioritized in tiers 1 and 2, with a points score based on six factors determining the specific priority order for allocation. RESULTS: The 1998 NKAS allocated approximately half the kidneys from DHB donors to the national transplant list and resulted in significantly improved HLA matching, more than doubling the proportion of transplants that were 000 HLA-A, -B, and -DR mismatched from 7% to 16% for adults. Pediatric patients achieved comparable levels of HLA matching to adult patients for the first time in the United Kingdom through improved access to adult donor organs. The scheme also benefited highly sensitized patients and improved equity with regard to patient blood group, rareness of HLA type, and HLA homozygosity. CONCLUSION: The 1998 NKAS represented a significant advance for the allocation of DHB donor kidneys in the United Kingdom and, while not addressing inequities in access to transplant, it did largely achieve the principal goal of improving HLA matching.

A New UK 2006 National Kidney Allocation Scheme for deceased heart-beating donor kidneys.

INTRODUCTION: In 2004, it was agreed that a new allocation scheme for kidneys from deceased heart-beating donors was required in the United Kingdom to address observed inequities in access to transplant. The 2006 National Kidney Allocation Scheme (2006 NKAS) was developed to meet agreed objectives and preparatory work included a review of the criteria for human leukocyte antigen (HLA) matching and simulation evidence about the effectiveness of alternative schemes. ALGORITHM FOR 2006 NKAS: The 2006 NKAS gives absolute priority to all 000 HLA-A, -B, -DR-mismatched patients and well-matched pediatric patients (<18 years), and then a points score defines priorities for allocation with waiting time being most influential. Points for age and HLA mismatch are linked in a novel approach to ensure well-matched transplants for younger patients while recognizing that HLA matching is less important for older patients as retransplantation is less likely to be required. To improve equity for difficult to match patients, rare HLA specificities were defaulted to more common, related specificities. IMPACT OF 2006 NKAS: After 3 years, the scheme is already making good progress in achieving its objectives, with overall results similar to those observed in the simulations. There has been a significant benefit for patients waiting more than 5 years for transplant. A number of other advantages of the scheme are also apparent with equity of access improving in many respects, including the achievement of equity of access to transplant for HLA-DR homozygous patients, but geographical inequity of access will take a number of years to address fully.

Factors influencing outcome after deceased heart beating donor kidney transplantation in the United Kingdom: an evidence base for a new national kidney allocation policy.

BACKGROUND: Outcomes after deceased heart beating donor kidney transplantation are good, but survival rates vary according to a number of donor-, recipient-, and transplant-related factors. This comprehensive analysis of transplant outcomes was undertaken to inform development of a new Kidney Allocation Scheme. METHODS: A complete case analysis of the outcome of kidney-only transplants in the United Kingdom, 1995 to 2001, was undertaken using Cox regression modeling. Seven thousand three hundred eighty-five (77%) of the 9585 transplants reported to the UK Transplant Registry were primary transplants in adults. Regrafts and pediatric patients (age <18 years) were analyzed separately. Transplant and patient survival over 5 years were investigated in addition to causes of prolonged cold ischemia time (CIT). RESULTS: A variety of factors significantly adversely influenced kidney transplant and patient outcome, including older donor age, older recipient age, waiting time to transplant over 2 years, diabetes, and earlier year of transplant. Human leukocyte antigen mismatch and CIT were significant in analyses of transplant but not in patient outcome, and an increased graft failure rate was also identified in adolescent patients. CIT was prolonged by long-distance kidney exchanges between centers (2 hr) and reallocation of kidneys for alternative patients (7 hr). CONCLUSION: This study identified a number of factors that influence transplant outcome after deceased heart beating donor kidney transplant in the United Kingdom. The findings suggest that the influences of human leukocyte antigen mismatch and CIT are most relevant in considering a revised kidney allocation scheme.