David K. Imagawa

In situ splitting of the cadaveric liver for transplantation

BACKGROUND The shortage of cadaveric donor livers is the rate-limiting step in clinical liver transplantation. Split liver transplantation provides a means to expand the cadaveric donor pool. However, this concept has not reached its full potential because of inferior patient and graft survival and high complication rates when traditional ex vivo split techniques are used. Therefore we sought to evaluate the safety, applicability, and effectiveness of a new technique for split liver transplantation. METHODS This study consists of 15 in situ split liver procurements, which resulted in 28 liver transplants. In situ splitting of selected livers from hemodynamically stable cadaveric donors was performed at the donor hospital without any additional work-up or equipment being needed. In situ liver splitting is accomplished in a manner identical to the living-donor procurement. This technique for liver splitting results in a left lateral segment graft (segments 2 and 3) and a right trisegmental graft (segments 1 and 4-8). This procedure required the use of the donor hospital operating room for an additional 1.5-2.5 hr and did not interfere with the procurement of 30 kidneys, 12 hearts, 7 lungs, and 9 pancreata from these same donors. RESULTS The 6-month and 1-year actuarial patient survival rates were 92% and 92%, respectively, while the 6-month and 1-year actuarial graft survival rates were 86% and 86%, respectively. The 6-month and 1-year actuarial patient survival rate of patients who received a left lateral segment graft was 100% and 100%, respectively, while those who received a right trisegmental graft had 6-month and 1-year rates of 86% and 86%, respectively. The actuarial death-censored graft survival rates at 6 months and 1 year were 80% and 80%, respectively, for the left lateral segment grafts, and 93% and 93%, respectively, for the right trisegmental grafts. Alograft and patient survival was independent of United Network for Organ Sharing status at the time of liver transplantation. No patient developed a biliary stricture, required re-exploration for intra-abdominal hemorrhage, or suffered from portal vein, hepatic vein, or hepatic artery thrombosis CONCLUSIONS In situ split liver transplantation can be accomplished without complications and provides results that are superior to those obtained previously with ex vivo methods. It abolishes ex vivo benching and prolonged ischemia times and provides two optimal grafts with hemostasis accomplished. This technique decreases pediatric waiting time and allows adult recipients to receive right-sided grafts safely. In situ splitting is the method of choice for expanding the cadaveric liver donor pool.

Orthotopic liver transplantation for hepatitis C : Outcome, effect of immunosuppression, and causes of retransplantation during an 8-year single-center experience

OBJECTIVE To determine the outcome of orthotopic liver transplantation (OLT) for end-stage liver disease caused by hepatitis C virus (HCV). SUMMARY BACKGROUND DATA HCV has become the leading cause of cirrhosis and hepatic failure leading to OLT. Recurrent HCV after OLT is associated with significant complications and may lead to graft loss that requires retransplantation (re-OLT). The authors studied the outcome of transplantation for HCV, the effect of primary immunotherapy, and causes of retransplantation. METHODS The authors conducted a retrospective review of their experience during an 8-year period (1990-1997), during which 374 patients underwent transplants for HCV (298 [79.6%] received one OLT; 76 [20.4%] required re-OLT). Median follow-up was 2 years (range 0 to 8.3). Immunosuppression was based on cyclosporine in 190 patients and tacrolimus in 132 patients. In a third group of patients, therapy was switched from cyclosporine to tacrolimus or from tacrolimus to cyclosporine (cyclosporine/tacrolimus group). RESULTS Overall, 1-, 2-, and 5-year actuarial patient survival rates were 86%, 82%, and 76%, respectively. The 2-year patient survival rate was 81 % in the cyclosporine group, 85% in the tacrolimus group, and 82% in the cyclosporine/tacrolimus group. In patients receiving one OLT, overall 1-, 2-, and 5-year patient survival rates were 85%, 81%, and 75%, respectively. The 2-year patient survival rate was 79% in the cyclosporine group, 84% in the tacrolimus group, and 80% in the cyclosporine/tacrolimus group. The overall graft survival rates were 70%, 65%, and 60% at 1, 2, and 5 years, respectively. The graft survival rate at 2 years was similar under cyclosporine (68.5%), tacrolimus (64%), or cyclosporine/tacrolimus (60%) therapy. Re-OLT was required in 42 (11.2%) patients for graft dysfunction in the initial 30 days after OLT. Other causes for re-OLT included hepatic artery thrombosis in 10 (2.6%), chronic rejection in 8 (2.1%), and recurrent HCV in 13 (3.4%) patients. The overall survival rates after re-OLT were 63% and 58% at 1 and 2 years. The 1-year survival rate after re-OLT was 61 % for graft dysfunction, 50% for chronic rejection, 60% for hepatic artery thrombosis, and 60% for recurrent HCV. At re-OLT, 85.3% of the patients were critically ill (United Network for Organ Sharing [UNOS] status 1); only 14.7% of the patients were UNOS status 2 and 3. In re-OLT for chronic rejection and recurrent HCV, the 1-year survival rate of UNOS 1 patients was 38.4%, compared with 87.5% for UNOS 2 and 3 patients. In patients requiring re-OLT, there was no difference in the 1-year patient survival rate after re-OLT when cyclosporine (60%), tacrolimus (63%), or cyclosporine/tacrolimus (56%) was used for primary therapy. With cyclosporine, three patients (1.5%) required re-OLT for chronic rejection versus one patient (0.7%) with tacrolimus. Re-OLT for recurrent HCV was required in four (3%) and seven (3.6%) patients with tacrolimus and cyclosporine therapy, respectively. CONCLUSIONS Orthotopic liver transplantation for HCV is performed with excellent results. There are no distinct advantages to the use of cyclosporine versus tacrolimus immunosuppression when patient and graft survival are considered. Re-OLT is an important option in the treatment of recurrent HCV and should be performed early in the course of recurrent disease. Survival after re-OLT is not distinctively affected by cyclosporine or tacrolimus primary immunotherapy. The incidence of re-OLT for recurrent HCV or chronic rejection is low after either tacrolimus or cyclosporine therapy.

Correlation between donor age and the pattern of liver graft recovery after transplantation

We have observed an increased rate of delayed non-function (DNF) of liver grafts procured from older donors. The aim of this study was to correlate donor age and the patterns of graft failure after transplantation. Pattern of liver injury, synthetic function, and graft survival in recipients receiving liver grafts from donor older than age 50 (group I, n=95) were compared with matched cohort of recipients transplanted with grafts from donors age 20–30 (group III, n=50). Primary nonfunction (PNF) of the graft was defined as non-recoverable hepatocellular function necessitating emergency retransplantation within 72 hr. DNF was defined as marginal graft function necessitating re-transplantation within one month. Recipient characteristics, including age and preoperative UNOS status, were similar between groups. Ischemic/reperfusion injury, reflected by SGOT and SGPT was more severe in older donors. PNF occurred at similar frequencies for all groups (7%). Normal liver function was regained in 76% of recipients in group I, and in 92% in group II. However, cholestatic pattern was observed in recipient of grafts from group I donors. Rapid rise in bilirubin, despite normalization of prothrombin time and liver transaminases, was the hallmark of DNF. DNF resulted in higher retransplantation rate in group I (24% vs. 8% in group II). Donor age did not affect patient survival. Liberalizing criteria for donor selection, and acceptance of older donors is a calculated risk. Over 75% of the recipients will regain normal liver function. However, a higher number of these grafts will exhibit slow recovery after transplantation, and a significant rate of DNF. Recognition of such

Adjuvant chemotherapy improves survival after liver transplantation for hepatocellular carcinoma

ObjectiveThe aim of this study was to evaluate the effect of postoperative adjuvant chemotherapy on the recurrence rate and survival of patients after orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC). Summary Background DataHistorically, liver transplantation for HCC has yielded poor long-term survival. Multimodality therapy has been initiated in an effort to improve survival statistics. MethodsTwenty-five patients were placed on 6 months of intravenous fluorouracil, doxorubicin, and cisplatin after OLT. Risk factors, recurrence rates, and survival rates were analyzed and compared with historic controls. ResultsOverall long-term survival in the protocol patients was 46% at 3 years, improved over our historic controls of 5.8% at 3 years (p = 0.0001). Overall recurrence rate was 20% (n = 4). Possible risk factors, such as tumor size, vascular invasion, multifocality, capsular invasion, and tumor differentiation, were not found to be significantly predictive of survival. Three patients with long-term, disease-free survival had tumors > 5 cm. Side effects from chemotherapy were common, but rarely severe. ConclusionsThis study suggests that adjuvant chemotherapy after transplantation for HCC can provide long-term cure and may improve survival, even in patients with stage III and IV disease.

Predictors of Survival After In Vivo Split Liver Transplantation: Analysis of 110 Consecutive Patients

ObjectiveTo determine the factors that influence patient survival after in vivo split liver transplantation (SLT). Summary Background DataSplit liver transplantation is effective in expanding the donor pool, and its use reduces the number of deaths in patients awaiting orthotopic liver transplantation. Early SLTs were associated with poor outcomes, and acceptance of the technique has been slow. A better understanding of the factors that influence patient and graft survival would be useful in widening the application of SLT. MethodsDuring a 3.5-year period, 55 right and 55 left lateral in vivo split grafts were transplanted in 102 pediatric and adult recipients. The authors’ in vivo split technique has been previously described. Median follow-up was 14.5 months. Recipient, donor, and surgical variables were analyzed for their effect on patient survival after SLT. ResultsOverall survival rates of patients who received an SLT were not significantly different from those of patients who received whole organ transplants. Survival of left lateral segment recipients, at median follow-up time, was 76% versus 80% in patients receiving a trisegment. Fifty of 102 patients (49%) were high-risk urgent recipients (United Network for Organ Sharing [UNOS] status 1 and 2A) and 52 (51%) were nonurgent recipients (UNOS status 2B, 3). High-risk recipients had a survival rate significantly lower than that of nonurgent recipients. By univariate comparison, two variables—UNOS status and number of transplants per patient—were significantly associated with an increased risk of death. Preoperative recipient mechanical ventilation, preoperative prothrombin time, donor sodium level, donor length of hospital stay, and warm ischemia time approached significance. The type of graft (right vs. left) did not reduce the survival rate after transplantation. Multivariate logistic regression analysis identified UNOS status and length of donor hospital stay as independent predictors of survival. ConclusionsPatient survival of in vivo SLT is not significantly different from that of whole-organ orthotopic liver transplantation. The variables affecting outcome of in vivo SLT are similar to those in whole-organ transplantation. in vivo SLT should be widely applied to expand a severely depleted donor pool.

Fas ligand gene transfer to renal allografts in rats : Effects on allograft survival

BACKGROUND Fas ligand (FasL) induces apoptosis of cells bearing its receptor Fas, and has been shown to be important in T-cell development and regulation and in immune privilege. We hypothesized that FasL expression by renal allografts might provide protection from rejection. METHODS The murine FasL cDNA was cloned into a replication-defective adenovirus (AdV-FasL). Protein expression was confirmed by immunostaining of AdV-FasL-transduced HeLa cells. Allogeneic kidney transplants were performed between WF (RT1u) donors and Lewis (RT1) recipients. Donor kidneys were perfused in situ with saline alone (control), or 9 x 10(9) plaque-forming units of AdV-FasL. One native kidney was removed at the time of transplant and the other at 6 or 7 days. Uremic death was the endpoint, and deaths within 7 days of transplant were excluded. Transduced allografts were stained for FasL expression using a monoclonal antibody and tested for FasL mRNA production by reverse transcriptase-polymerase chain reaction and Northern blotting. RESULTS Immunostaining of AdV-FasL-transduced allografts demonstrated efficient gene transfer lasting approximately 2 weeks, and FasL mRNA production in the AdV-FasL-transduced allografts was confirmed by Northern blotting and reverse transcriptase-polymerase chain reaction. Mean survival of animals with AdV-FasL-transduced renal allografts was 27.8 days vs. 11.6 days in control animals (P < 0.05). CONCLUSIONS (1) Adenoviral vectors can successfully transduce rat kidneys with the FasL cDNA. (2) FasL gene transfer prolongs rat renal allograft survival.

The role of tumor necrosis factor in allograft rejection. I. Evidence that elevated levels of tumor necrosis factor-alpha predict rejection following orthotopic liver transplantation.

Plasma levels of tumor necrosis factor-alpha were measured in 50 adult patients following orthotopic liver transplantation. The mean (+/- SEM) plasma concentration of TNF-alpha was significantly higher in patients experiencing a rejection episode (941 +/- 83 pg/ml) than in those with a stable clinical course (240 +/- 6 pg/ml; P = 0.0001). Peak levels of TNF-alpha were usually found at the time of clinically diagnosed rejection, although elevated levels were observed 1-2 days earlier. First-week peak TNF-alpha levels were significantly higher in patients who suffered graft loss (2146 +/- 788 pg/ml) than in those who were discharged from the hospital without clinical evidence of rejection (581 +/- 93 pg/ml; P = 0.004). TNF-alpha levels were not correlated with white blood cell count (r2 = 0.004), cyclosporine levels (0.01), serum creatinine (0.002), serum bilirubin (0.05), serum SGOT (0.03), or SGPT (0.05). TNF-alpha levels were not elevated in four cases of viral hepatitis occurring after transplantation. We conclude that circulating levels of TNF-alpha are elevated during liver allograft rejection and may precede clinical manifestations. First-week TNF-alpha levels are also useful predictors of long-term graft outcome. Further investigation is required to determine whether this monokine is important in the actual pathogenesis of allograft rejection.

Hyperlipidemia after liver transplantation : Natural history and treatment with the hydroxy-methylglutaryl-coenzyme A reductase inhibitor pravastatin

This study was designed to determine the frequency of hyperlipidemia after orthotopic liver transplantation and whether treatment with a hydroxy-methylglutaryl coenzyme A reductase inhibitor was safe and efficacious. Cholesterol levels were assessed in 45 consecutive adult liver transplants (mean +/- SE). Four of 22 patients on cyclosporine (CsA) (18%) and three of 23 patients on FK506 (13%) had levels >225 mg/dl at 12 months (cholesterol levels for patients on CsA [total n=22]: pre-Tx = 140+/-11, 1 month = 183+/-36,3 months = 221+/-12, 6 months = 211+/-11, 12 months = 202+/-14 [P<0.01 vs. pre-Tx]; FK506 [total n=23]: Pre-Tx = 151+/-13, 1 month = 187+/-22, 3 months = 188+/-10, 6 months = 184+/-13, 12 months = 164+/-9 [P=0.02 vs. CsA]). A separate cohort of patients with stable graft function, cholesterol >225 mg/dl, and two additional risk factors for coronary artery disease were started on pravastatin. Ninety-eight patients were enrolled. Sixteen patients (16%) discontinued the drug because of subjective complaints. No episodes of rhabdomyolysis or hepatotoxicity occurred (cholesterol levels for patients on CsA [total n=65]: pretreatment = 251+/-7, 6 months = 220+/-7 [P=0.01 vs. pretreatment], 12 months = 224+/-8 [P=0.01 vs. pretreatment]; FK506 [total n=17]: pretreatment = 251+/-17, 6 months = 219+/-17, 12 months = 208+/-17 [P=0.08 vs. pretreatment]). Natural killer cells isolated from normal volunteers (n=14) exhibited 27+/-9% specific lysis. Patients on FK506 or cyclosporine-based immunosuppression alone (n=11) exhibited 20+/-4% specific lysis. Standard immunosuppression plus pravastatin (n=10) decreased lysis to 0.2+/-10% (P<0.02 vs. controls and standard immunosuppression). We conclude: (1) posttransplant hyperlipidemia occurs less frequently in liver transplant patients than in renal or cardiac transplants; (2) pravastatin is safe and efficacious for cholesterol reduction in liver transplant patients; and (3) pravastatin coadministered with standard immunosuppression reduces natural killer cell-specific lysis in these recipients.

Significance of early aminotransferase elevation after liver transplantation

BACKGROUND We retrospectively reviewed 213 consecutive patients who received their first liver allograft between January 1 and December 31, 1993, in order to study the impact of ischemia/preservation/reperfusion injury (IPRI) on patient and graft outcome. METHODS The extent of IPRI was assessed by the peak value of aspartate aminotransferase (ASTmax) observed within the first 72 hr after transplant. For the purpose of univariate analysis, categorical classification of recipients was done based upon ASTmax as follows: group 1, ASTmax<600 U/L (n=46); group 2, ASTmax=600-2000 U/L (n=97); group 3, ASTmax>2000-5000 U/L (n=50), and group 4, ASTmax>5000 U/L (n=17). For multivariate analysis, stepwise Cox regression was performed with age, ASTmax, and United Network for Organ Sharing (UNOS) status as covariates. RESULTS Groups were comparable with respect to age, UNOS status at the time of transplantation, and diagnostic case mix. Median follow-up was 644 days. The overall incidence of primary graft nonfunction (PNF) was 7.6%. PNF incidence was significantly correlated with the severity of IPRI (0%, 4%, 10%, and 41% for groups 1 to 4, respectively, P < 0.0001), but this impact was confined to the respective rates of retransplantation as early patient survival was unaffected. The 1-year survival of patients whose initial grafts manifested extreme IPRI (group 4) was significantly inferior to recipients in the three other groups (77%, 71%, 73%, and 52% for groups 1 to 4, respectively, P=0.03). This increased mortality was confined to patients who never achieved discharge from their initial hospitalization, with no significant differences between groups being detected in the survival of those patients who were discharged (84%, 80%, 85%, and 81% for groups 1 to 4, respectively, P=NS). Although overall 1-year graft survival was strongly correlated with the extent of IPRI (77%, 67%, 62%, and 41% for groups 1 to 4, respectively, P=0.001), this correlation was abolished when survival of grafts not lost to PNF was examined at 1 and 2 years. Stepwise Cox regression analysis confirmed the independent association between ASTmax and patient and graft survival. The long-term quality of allograft function as well as the incidence of chronic rejection and biliary complications were unrelated to the extent of IPRI. CONCLUSIONS We conclude that: (1) patient survival is influenced by IPRI only when it is extreme (ASTmax>5000 U/L), provided parameters of graft function are used in conjunction with aminotransferase values to assess the need for prompt retransplantation; (2) short-term graft survival is proportional to the extent of IPRI, but grafts that are not lost to PNF have equivalent 1- and 2-year survival irrespective of the magnitude of IPRI; (3) 40% of grafts with extreme IPRI are lost to PNF, but the same proportion also provide long-term function; and (4) for surviving grafts, long-term biochemical function as well as the incidence of biliary complications and of chronic rejection are unrelated to the extent of IPRI.

Orthotopic liver transplantation for congenital biliary atresia. An 11-year, single-center experience.

OBJECTIVE The authors analyze a single centers 11-year experience with 190 orthotopic liver transplants for congenital biliary atresia. SUMMARY BACKGROUND DATA Hepatic portoenterostomy generally is the initial treatment for children with congenital biliary atresia. Despite multiple modifications of the hepatic portoenterostomy, two thirds of treated patients still develop recurrent cholestasis, portal hypertension, cholangitis, and cirrhosis. Therefore, the only hope of long-term survival in the majority of children with congenital biliary atresia is definitive correction with orthotopic liver transplantation. METHODS The medical records of 190 consecutive patients undergoing orthotopic liver transplantation for congenital biliary atresia from July 1, 1984 to February 29, 1996 were reviewed. Results were analyzed via Cox multivariate regression analysis to determine the statistical strength of independent associations between pretransplant covariates and patient and graft survival. Actuarial patient and graft survival was determined at 1, 2, and 5 years. The type and incidence of post-transplant complications were determined, as was the quality of long-term graft function. The median follow-up period was 3.21 years. RESULTS The liver grafts were comprised on 155 whole-organ, 24 reduced-size, and 11 living donor organs. Median pretransplant values for recipient age, weight, and total bilirubin were 1.4 years, 12.3 kg, and 13.8 mg/dL, respectively. One hundred sixty-four patients (86%) had undergone prior hepatic portoenterostomy. Eighty-seven patients (46%) were United Network for Organ Sharing (UNOS) status 1 or 2 at the time of liver transplantation. The majority (15/24, 62%) of reduced-size graft recipients were UNOS status I at the time of transplantation. One hundred fifty-nine patients (84%) received a single graft, whereas 31 patients required 37 retransplants. The 1, 2, and 5 year actuarial patient survival rates were 83%, 80% and 78% respectively, whereas graft survival rates were 81%, 77%, and 76%, respectively. Cox multivariate regression analysis demonstrated that pretransplant total bilirubin, UNOS status, and graft type significantly predicted patient survival, whereas recipient age, weight, and previous hepatic portoenterostomy did not. Current median follow-up values for total bilirubin and aspartate aminotransferase levels in the 154 surviving patients were 0.5 mg/dL and 34 international units/L, respectively. CONCLUSION Long-term patient survival after orthotopic liver transplantation for congenital biliary atresia is excellent and is independent of recipient age, weight, or previous hepatic portoenterostomy. Optimal results are obtained in this patient population when liver transplantation is performed before marked hyperbilirubinemia, and when possible, using a living-donor graft.