The use of donation after cardiac death (DCD) donor hepatic allografts is becoming more widespread; however, there have been published reports of increased graft failure from specific complications associated with this type of allograft. The complication of ischemic cholangiopathy (IC) has been reported to occur more frequently after the use of DCD hepatic allografts. We report the results of 52 liver transplants from DCD donors and the factors that influenced the development of IC. We conducted a retrospective review of all DCD and donation after brain death (DBD) donor liver recipients from September 2003 through December 2006 at a single institution. Survival and complication rates were compared between the 2 groups. The Cox proportional hazards model was then used to identify recipient and donor factors that predict the development of IC in the DCD group. There was no difference in 1-year patient or graft survival rates between the 2 groups. There was no incidence of primary nonfunction from the DCD allografts. Hepatic artery complications and anastomotic bile duct complications were comparable in the 2 groups. There was, however, an increased risk for the development of IC in the DCD group (13.7% versus 1%, P ϭ 0.001). Donor weight Ͼ100 kg and total ischemia times Ն9 hours, in donors older than 50 years of age, predicted the development of IC in the DCD group. In conclusion, there is a higher incidence of IC in recipients receiving DCD donor livers; however, patient and graft outcomes with DCD donors remain comparable to those with DBD donors. Careful donor selection may improve utilization of these grafts. Liver Transpl 14: 604-610, 2008.

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We previously reported an unexpected augmentation of mycophenolic acid (MPA) levels (trough and AUC0-12) in patients receiving mycophenolate mofetil (MMF) in combination with tacrolimus versus patients receiving the same dose of MMF in combination with cyclosporin A (CsA). This finding was accompanied by a corresponding reduction of the inactive glucuronide metabolite of MPA (MPAG) in patients, suggesting that tacrolimus may effect the conversion of MPA to MPAG by the enzyme UDP-glucuronosyltransferase (UDPGT). To investigate this possibility directly, UDPGT was extracted from human liver and kidney tissue and its activity was characterized using MPA as a substrate in vitro, assessing the conversion of MPA to MPAG using analysis by high-performance liquid chromatography. With crude microsomal preparations, amounts of UDPGT at least 100 times higher in specific activity (i.e., units to milligrams of protein) could be extracted per gram of tissue from kidney as opposed to liver. This result did not appear to be related to the coextraction of a liver-specific UDPGT inhibitor because initial enzyme kinetic values (Vmax and km) were identical for kidney and liver extracts, and further purification of the liver enzyme did not enhance activity (as is seen when inhibitors are removed during purification). With further UDPGT purification (approximately 200-fold) from kidney extracts using a combination of ammonium sulfate precipitation, followed by anion exchange, hydroxyapatite, and size exclusion chromatography, the enzyme was more than 80% pure when assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Initial enzyme kinetic analysis of this purified product showed a km value for MPA of 35.4+/-5.7 microg/mL and a Vmax of 2.87+/-0.31 MPAG produced per hour (n = 7). The addition of clinically relevant concentrations of CsA (200-1,000 ng/mL) or tacrolimus (10-25 ng/mL) resulted in a dose-dependent inhibition of the UDPGT enzyme by both agents with tacrolimus, which was approximately 60-fold more efficient as an inhibitor. The calculated inhibition constants (KI) of tacrolimus and CsA for the purified UDPGT were 27.3+/-5.6 ng/ml and 2,518+/-1473 ng/ml. respectively. Both agents displayed an inhibition profile characteristic of a competitive inhibitor (substrate) that could be demonstrated in a reciprocal experiment with CsA as a substrate, but not with tacrolimus. This finding suggested that the significantly more efficient inhibition of UDPGT by tacrolimus may occur by a more complicated mechanism that is yet to be determined.

The results suggest that dose and timing of DBMC infusions may be important variables affecting allograft survival. A randomized prospective trial is now in progress to compare group 3 DBMC infusion protocol with controls receiving OLTX alone.

The use of TEG is a helpful adjunct to SPK surgery, demonstrating the patient's current coagulation status. Nearly all SPK recipients (type 1 IDDM with ESRD) have been demonstrated to be hypercoagulable. The TEG allows the judicious use of anti-coagulation at the time of surgery, and beyond.