K. Hama

Application of machine perfusion preservation as a viability test for marginal kidney graft.

Background. This study evaluated the usefulness of machine perfusion preservation parameters as indicators of kidney graft viability. Methods. Eighty-eight cadaveric kidneys were analyzed in this study. Of these, 74 kidneys (84.1%) were procured from nonheartbeating donors. The criteria for an acceptable kidney for transplantation were a perfusion flow of more than 0.4 mL/min/g with a concurrent decreasing perfusion pressure. The average perfusion pressure was 30–50 mmHg. We divided the kidneys into three groups: group 1 (n=35), 0.45–0.65 mL/min/g machine perfusion flow (MPF); group 2 (n=30), 0.65–0.90 mL/min/g MPF; and group 3 (n=23), more than 0.9 mL/min/g MPF. Results. A higher rate of primary nonfunction (PNF; 25.7%) was found in group 1, compared with 6.7% in group 2 and 0% in group 3. A higher rate of 30.4% immediate function was found in group 3, compared with 16.7% in group and 8.6% in group 1. However, a longer period of acute tubular necrosis (ATN; 12.0 days) was found in group 1 compared with 8.6 days in group 2 and 8.7 days in group 3. PNF was detected in 7 (77.8%) cases with more than 16 hr of total ischemic time (TIT) in group 1. In contrast, all of nine cases with more than 16 hr of TIT in group 3 were functional. Conclusions. MPF is a reliable indicator of graft viability based on the rate of PNF and immediate renal allograft function, especially in marginal donors.

Safety and efficacy of conversion from twice-daily tacrolimus (prograf) to once-daily prolonged-release tacrolimus (graceptor) in stable kidney transplant recipients.

BACKGROUND Graceptor is a new modified-release once-daily formulation of tacrolimus with an efficacy and safety profile similar to twice-daily tacrolimus (Prograf), as identified by clinical trials, offering a more convenient dosing regimen to improve adherence. The aim of this study was to analyze the safety of a 1:1 dose conversion from twice-daily Prograf to once-daily Graceptor in stable kidney transplant recipients. METHODS We switched 33 Japanese patients who had undergone kidney transplantation ≥1 years before from twice-daily Prograf to once-daily Graceptor. The dose conversion ratio between Prograf and Graceptor was 1:1. We compared the following parameters: minimum tacrolimus concentration (C(min)); concentration dose per weight (CDW); serum creatinine (sCr); blood urea nitrogen (BUN); total cholesterol (TC); high-density lipoprotein cholesterol (HDL-C); uric acid (UA); fasting blood sugar (FBS). Time points for measurements were 1 month before study start and 1 and 2 months afterward. RESULTS The mean age of the subjects in this study was 46.5 ± 13.1 years. Mean C(min) decreased from 4.55 ± 1.79 to 3.20 ± 1.22 ng/dL. The mean CDW also decreased, from 99.8 ± 69.5 to 75.0 ± 55.1 mg/dL/kg over the 2 months. There were no significant changes in sCR, BUN, UA, and FBS. Mean TC increased from 187.5 ± 51.4 to 194.3 ± 43.4 mg/dL, and mean HDL-C changed from 53.7 ± 12.0 to 56.1 ± 11 mg/dL. There were no episodes of rejection or infection. CONCLUSIONS We conclude that switching from Prograf to Graceptor is safe and has the advantage of improving adherence. It could also have a beneficial effect in controlling glycemic levels and the adverse effects of tacrolimus. In many cases (25%-30%), the minimum concentration of tacrolimus decreased after changing tablets. With Graceptor, the ratio of area under trough level to area under the curve (AUC) is low compared with Prograf, resulting in low C(min) values of 1-2 ng/mL, and the AUC for Graceptor is very similar to that for Prograf.

Evidence of Different Pharmacokinetics Between Cyclosporine and Tacrolimus in Renal Transplant Recipients: Why Cyclosporine Is Monitored by C2 Level and Tacrolimus by Trough Level

The clinical efficacy of calcineurin inhibitors administered to renal transplant recipients is considered to be a strong function of the area under the concentration time curve (AUC). Monitoring of blood concentrations for two similar calcineurin inhibitors, cyclosporine (CyA) and tacrolimus (TAC) are different. Namely, CyA blood concentration is usually monitored at two hours after administration (C2), a surrogate for peak concentration (Cp), and TAC at trough concentration (Ct). We examined the behavior of blood concentration curves simultaneously for both CyA and TAC in renal transplant recipients with similar clinical backgrounds. Furthermore, we analyzed the correlation of Cp and Ct vs AUC implementing an area under the trough level, or area above the trough level as new pharmacokinetic parameters, so that C2 for CyA and Ct for TAC has validated using controlled clinical data. We observed differences in the pharmacokinetics between.

Biliary Complications After 52 Adult Living Donor Liver Transplantations: A Single-Center Experience

OBJECTIVE The incidence of biliary complications after adult living donor liver transplantation (ALDLT) are still high even though various devices have been reported to overcome them. METHOD From October 2000 to April 2007, we performed 52 ALDLTs which included 15 ABO-incompatible grafts. Median follow-up was 565 days. In 49 procedures, we used duct-to-duct anastmosis with a stent inserted in the recipient duct and out through the common bile duct wall as an external stent, and in 3 procedures, we used duct-to-jejunostomy anastomosis. We investigated postoperative biliary complications and their management. RESULTS Forty-four patients received right lobe grafts and 8 received left lobe grafts. Among patients in whom duct-to-duct anastomosis was used, nine (20.5%) developed biliary complications including bile leakage in five and biliary strictures in four. All bile leakage was treated with reoperation. Three biliary strictures were treated with stent placement, and one biliary stricture was treated with magnetic compression anastomosis. Among the three patients in whom duct-to-jejunostomy was used, two (66.7%) had bile leakage and stricture, respectively. Two of four ABO-incompatible patients (50%) had hepatic artery thrombosis with biliary complications, a high incidence. CONCLUSION In our series of ABO-incompatible patients undergoing ALDLT, those who developed hepatic artery thrombosis exhibited a high incidence of biliary complications.

Early Steroid Withdrawal in Adult Kidney Transplantation at a Single Center

BACKGROUND Beneficial effects of protocols using minimal steroid exposure have been recently reported. The purpose of this study was to evaluate the outcomes of kidney transplantation recipients who received immunosuppression protocols with early steroid withdrawal (ESW) at our center. METHODS We retrospectively studied 84 kidney transplant recipients who had received ESW immunosuppressive protocols at our center from March 2005 to December 2010. The immunosuppressive regimen was a combination of calcineurin inhibitors (tacrolimus/cyclosporine), methylprednisolone, which was tapered and discontinued within 2 months, mycophenolate mofetil, and basiliximab (postoperative days 0 and 4). We compared the outcomes of our ESW recipients with those of a historical control group (February 2003 to January 2005; n = 18). RESULTS Clinical acute rejection episodes were observed in 15 (17.9%) and 5 (27.8%) cases in the ESW and control groups, respectively. Cytomegalovirus infection occurred in 12 (14.3%) and 5 (27.8%) cases in the ESW and control groups, respectively. The creatinine levels at 1 year after transplantation were 1.3 ± 0.4 mg/dL and 1.3 ± 0.5 mg/dL in the ESW and control groups, respectively. In the ESW group of 84 recipients, actuarial patient survival at 1 year was 94.0%. In the historical group of 18 recipients, the actuarial patient survival at 1 year was 100% (P = .76). In the ESW group the graft survival rate at 1 year was 95.2%. In the historical group, graft survival rate at 1 year was 100% (P = .65). There were no significant differences in the parameters between the groups. CONCLUSIONS The outcomes from this study were considered to be acceptable; however, the possibility of improving the protocols exists.

ABO-Incompatible Adult Living Donor Liver Transplantation for Hepatocellular Carcinoma

Living donor liver transplantation (LDLT) offers timely transplantation for patients with hepatocellular carcinoma (HCC). If ABO-incompatible LDLT is feasible, the need for pretransplantation treatment may be eliminated, which may reduce overall morbidity. In this article, we have described 8 adult HCC patients who successfully underwent LDLT from ABO-incompatible donors. Antirejection therapy included multiple preoperative plasmaphereses, splenectomy, and an immunosuppressive regimen with tacrolimus, methylprednisolone, and mycophenolate mofetil. The maintenance dose of immunosuppression did not differ from that of the ABO-identical cases. In addition, we also performed intrahepatic arterial infusion of prostaglandin E1. In 5 patients, we administered a single dose of rituximab, a chimeric CD20 monoclonal antibody. As a result of this treatment, 6/8 patients are still alive. Our experience has shown that it is possible to control antibody-mediated humoral rejection and other complications in adult ABO-incompatible LDLT.

How Can We Increase Living Related Donor Renal Transplantations

BACKGROUND In Japan, living donor renal transplantation has gained momentum due to an increased number of patients with end-stage renal disease. Living donation not only provides better outcomes, but also the recipients usually need less medications, thereby increasing the quality of life and reducing the potential side effects of immunosuppression. MATERIALS AND METHODS For the past 25 years, our center had performed 140 open donor nephrectomy (OPNx) renal transplantations. Since July 2003, we changed our procurement operation to living hand-assisted laparoscopic donor nephrectomy (HALNx) in 49 cases. Our operative technique consisted of two 12-mm ports placed in the midaxillary line at the superior and inferior levels of the umbilicus. Next, a 5-cm incision was made in the midline periumbilicus and the hand port system fitted through a midline abdominal incision. RESULTS In 49 cases, HALNx was completed successfully; no patient required conversion to laparotomy. The estimated blood loss was 33.0 +/- 43.4 g and no patient required blood transfusion. In comparison, in OPNx the blood loss was 426.5 +/- 247.6 g (P < .001). The mean operative times were 167.4 +/- 39.7 minutes for HALNx and 228.4 +/- 35.7 minutes for OPNx (P < .001). The postoperative hospital stays were 9.1 +/- 3.8 days for HALNx and 13.0 +/- 1.9 days for OPNx (P < .001). For 3 years prior to introduction of HALNx, we had performed only 10 living donor renal transplantations. Since the introduction of HALNx in 2003, the number of living donors has tripled during the following 3 years. CONCLUSIONS Herein we have reported that HALNx was superior in terms of less operative time and blood loss, postoperative pain and recovery, and shorter hospital stay. Overall donor patient satisfaction was also better in the HALNx group. HALNx is a safe procedure that makes kidney donation more appealing to potential live donors and has increased the living donor pool at our center.

Long-term follow-up ABO-incompatible adult living donor liver transplantation in cirrhotic patients.

Abstract:  ABO‐incompatible liver transplantation is usually contraindicated. The presence in the recipient of preformed anti‐A/B antibodies located on endothelial cells raises the risk of antibody‐mediated humoral rejection of the graft. We describe four successful cases of steroid withdrawal in adult patients who had living‐donor liver transplantation from ABO‐incompatible donors. Antirejection therapy included multiple perioperative plasmapheresis, splenectomy, and a triple immunosuppressive regimen with tacrolimus, methylprednisolone (MPSL), and cyclophosphamide or mycophenolate mofetil (MMF). The maintenance dose of immunosuppression did not differ from that of ABO‐identical cases. After transplantation, intrahepatic arterial infusion therapy with prostaglandin E1 (PG E1) was used. As a result, all four patients were able to achieve long‐term graft survival without steroid use. They all have good liver function and are leading normal lifestyles. Our experience with these four patients suggests the feasibility of controlling humoral rejection and other complications in adult ABO‐incompatible living donor liver transplantations with intrahepatic arterial infusion of PGE1, splenectomy, and plasmapheresis with a regular base of immunosuppression protocol to prevent antibody‐mediated humoral rejection.

RADIAL FLOW BIOREACTOR FOR THE CREATION OF BIOARTIFICIAL LIVER AND KIDNEY

A radial flow bioreactor (RFB) is used for a three-dimensional perfusion culture of hepatocellular carcinoma (HCC) cells and renal cells, to create a bioartificial liver and kidney. The cylindrical reactor is filled with porous cellulose microcarrier. RFB can be characterized as a system in which the medium flows from the periphery toward the center of the reactor, thereby delivering an adequate supply of oxygen and nutrients to cells at the center as well as at the periphery. HCC cells incubated in the RFB system at high density maintained viability for long periods of time. Proximal tubular cells (LLC-PK1) as well as HCC cells, but not human immortalized mesangial cells (HMC) were cultured in the RFB for more than 14 days. The mRNA expression of some enzymes involved in the urea cycle, cytochrome P450s in HCC cells, and the 1-alpha-hydroxylase (CYP27B1) in LLC-PK1 cells was higher than that in monolayer cultures. These results suggest that the RFB system composed of HCC cells or renal cells may be useful for a bioartificial liver and kidney.