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BACKGROUND: Liver transplantation from donation after cardiac death (DCD) donors is an increasingly common approach for expansion of the donor organ supply. However, transplantation with DCD livers results in inferior graft survival. In this study, we examined donor and recipient characteristics that are associated with poor allograft outcomes and present a set of criteria that permit allograft survival that is comparable to that of donation after brain death (DBD) grafts in both low- and high-risk recipients. METHODS: The United Network for Organ Sharing/Organ Procurement and Transplantation Network Liver Transplantation Registry between January 1996 and March 2006 was investigated. Adult DCD liver transplants (n = 874) were included. RESULTS: A DCD risk index was developed using the statistically significant factors from a multivariate Cox model: history of previous transplantation, life support status at transplantation, donor age, donor warm ischemia time (DWIT), and cold ischemia time (CIT). Favorable DCD donor criteria were donor age < or =45 years, DWIT < or =15 min, and CIT < or =10 hr. Four risk groups were developed based upon index scores that showed different graft survival. Graft survival of the favorable DCD group (84.9% at 1 year, 75.2% at 3 years, and 69.4% at 5 years) was comparable to that for DBD liver transplantation irrespective of recipient condition. Increasing donor age was more highly predictive of poor outcomes in DCD compared to DBD, especially in recipients in poor preoperative condition. CONCLUSIONS: DCD livers from young donors with short DWIT and CIT should be given greater consideration in order to expand the number of available donor organs.

Aberrant promoter hypermethylation, also known as epigenetics, is thought to be a promising biomarker approach to diagnose malignancies. Kidney repair after injury is a recapitulation of normal morphogenesis, with similarities to malignant transformation. We hypothesized that changes in urine epigenetics could be a biomarker approach during early kidney transplant injury and repair. We examined urine DNA for aberrant methylation of two gene promoters (DAPK and CALCA) by quantitative methylation-specific polymerase chain reaction from 13 deceased and 10 living donor kidney transplant recipients on postoperative day 2 and 65 healthy controls. Results were compared with clinical outcomes and to results of the kidney biopsy. Transplant recipients were significantly more likely to have aberrant hypermethylation of the CALCA gene promoter in urine than healthy controls (100% vs 31%; P < .0001). There was increased CALCA hypermethylation in the urine of deceased versus living donor transplants (21.60 +/- 12.5 vs 12.19 +/- 4.7; P = .04). Furthermore, there was a trend toward increased aberrant hypermethylation of urine CALCA in patients with biopsy-proven acute tubular necrosis versus acute rejection and slow or prompt graft function (mean: 20.40 +/- 6.9, 13.87 +/- 6.49, 17.17 +/- 13.4; P = .67). However, there was no difference of CALCA hypermethylation in urine of patients with delayed graft function versus those with slow or prompt graft function (16.9 +/- 6.2 vs 18.5 +/- 13.7, respectively; P = .5). There was no aberrant hypermethylation of DAPK in the urine of transplant patients. Urine epigenetics is a promising biomarker approach for acute ischemic injury in transplantation that merits future study.

Biopsies of ABO-incompatible and positive crossmatch (HLA-incompatible) renal allografts were retrospectively examined to compare results of C4d and C3d staining, and the correlation between such staining and histologic findings suggestive of antibody-mediated rejection (AMR). A total of 75 biopsies (55 protocol, 17 for graft dysfunction, 3 for other indications) of 24 ABO-incompatible grafts and 244 biopsies (103 protocol, 129 for graft dysfunction, 12 for other indications) of 66 HLA-incompatible grafts were examined; all were stained for C4d and approximately 40% for C3d. In ABO-incompatible grafts, 80% of protocol biopsies and 59% performed for graft dysfunction showed C4d staining in peritubular capillaries (PTC); this staining was not correlated with neutrophil margination in PTC. In HLA-incompatible grafts, PTC C4d was present in 26% of protocol biopsies and 60% of biopsies for graft dysfunction; 92% of biopsies with >1+ (0-4+ scale), diffuse PTC C4d had > or =1+ margination and/or thrombotic microangiopathy (TMA), compared with 12% of C4d-negative biopsies. C3d was somewhat more predictive of margination than C4d in ABO-incompatible, but not HLA-incompatible, grafts. In summary, while PTC C4d deposition indicates probable AMR in biopsies of HLA-incompatible grafts, including protocol biopsies, there is no histologic evidence that C4d deposition is correlated with injury in most ABO-incompatible grafts.

Adult-to-adult living donor liver transplantation is an increasingly important option for 17000 patients awaiting liver transplantation in the United States. However, adult-to-adult living donor liver transplantation volumes peaked in 2001 (N = 518), and have gradually fallen in 2002 (N = 362), 2003 (N = 321), and 2004 (N = 323). Recent concerns about donor safety and ethical considerations have made careful analysis of donor availability and selection criteria critically important. We conducted a retrospective review of our active liver transplant recipient registry (N = 251) and compared it to our living donor registry (N = 231), which included all potential living donors before the selection process. Fifteen percent of recipients accounted for the majority (53%) of donor evaluations, whereas 42% of recipients did not have even a single donor evaluation. Recipient diagnosis appears to have a significant impact on donor availability, with donors rarely evaluated for patients with alcoholic cirrhosis. Careful and stringent selection criteria rule out 67% of potential donors.

The number of candidates awaiting liver transplantation continues to exceed the available donor organ pool. This steadily increasing donor organ shortage calls for the widening of selection criteria for potential donor organs. Strategies to increase the number of liver allografts include liver splitting, use of donors over 70 years, use of steatotic donor livers, and reutilization of liver allografts after brain death of the first recipient. We report the successful use of a polycystic donor liver and review the experience with this donor population. We propose that the selective use of polycystic donor livers containing small (<5 cm) cysts with preserved liver parenchyma is safe and appropriate.