Novel benchmark values for redo liver transplantation – does the outcome justify the effort?

Objective

In the era of organ shortage, redo liver transplantation (reLT) is frequently discussed in terms of expected poor outcome, high cost and therefore wasteful resources. However, there is a lack of benchmark data to reliably assess outcomes after reLT. The aim of this study was to define the ideal reLT case, and to establish clinically relevant benchmark values for best achievable outcome in reLT.

Methods

We collected data on reLT between January 2010 and December 2018 from 22 high volume transplant centers on three continents. Benchmark cases were defined as recipients with model of end-stage liver disease score <=25, absence of portal vein thrombosis, no mechanical ventilation before surgery, receiving a graft from a donor after brain death. In addition, early reLT including those for primary non-function (PNF) were excluded. Clinically relevant endpoints covering intra- and postoperative course were selected and complications were graded by severity using the Clavien-Dindo classification and the comprehensive complication index (CCI). The benchmark cutoff for each outcome was derived from the 75th percentile of the median values of all benchmark centers, indicating the “best achievable” result. To assess the utility of the newly established benchmark values, we analyzed patients who received reLT for PNF (non-benchmark patients).

Results

Out of 1110 reLT 413 (37.2%) qualified as benchmark cases. Benchmark values included: Length of intensive care unit and hospital stay: <=6 and <=24 days, respectively; Clavien-Dindo grade >=3a complications and the CCI at 1 year: <=76% and <=72.2, respectively; in-hospital and 1-year mortality rates: <=14.0% and <=14.3%, respectively. The cutoffs for transplant-specific complications such as biliary complications at 1 year, outflow problems at 1 year and hepatic artery thrombosis at discharge were <=27.3%, <=2.5% and <=4.8%, respectively. Patients receiving a reLT for PNF showed mean outcome values all outside the reLT benchmark values. In-hospital mortality rate was 34.4% and the mean CCI at discharge 68.8.

Conclusion

ReLT remains associated with high morbidity and mortality. The availability of benchmark values for outcome parameters of reLT may serve for comparison in any future analyses of individuals, patient groups, or centers, but also in the evaluation of new therapeutic strategies and principles.

HIV-infected liver and kidney transplant recipients: 1- and 3-year outcomes

Improvements in human immunodeficiency virus (HIV)-associated mortality make it difficult to deny transplantation based upon futility. Outcomes in the current management era are unknown. This is a prospective series of liver or kidney transplant recipients with stable HIV disease. Eleven liver and 18 kidney transplant recipients were followed for a median of 3.4 years (IQR [interquartile range] 2.9-4.9). One- and 3-year liver recipients' survival was 91% and 64%, respectively; kidney recipients' survival was 94%. One- and 3-year liver graft survival was 82% and 64%, respectively; kidney graft survival was 83%. Kidney patient and graft survival were similar to the general transplant population, while liver survival was similar to the older population, based on 1999-2004 transplants in the national database. CD4+ T-cell counts and HIV RNA levels were stable; and there were two opportunistic infections (OI). The 1- and 3-year cumulative incidence (95% confidence intervals [CI]) of rejection episodes for kidney recipients was 52% (28-75%) and 70% (48-92%), respectively. Two-thirds of hepatitis C virus (HCV)-infected patients, but no patient with hepatitis B virus (HBV) infection, recurred. Good transplant and HIV-related outcomes among kidney transplant recipients, and reasonable outcomes among liver recipients suggest that transplantation is an option for selected HIV-infected patients cared for at centers with adequate expertise.

Liver transplantation for hepatocellular carcinoma: validation of the UCSF-expanded criteria based on preoperative imaging

We previously suggested that in patients with heptocellular carcinoma (HCC), the conventional Milan criteria (T1/T2) for orthotopic liver transplantation (OLT) could be modestly expanded based on pathology (UCSF criteria). The present study was undertaken to prospectively validate the UCSF criteria based on pretransplant imaging. Over a 5-year period, the UCSF criteria were used as selection guidelines for OLT in 168 patients, including 38 patients exceeding Milan but meeting UCSF criteria (T3A). The 1- and 5-year recurrence-free probabilities were 95.9% and 90.9%, and the respective survivals without recurrence were 92.1% and 80.7%. Patients with preoperative T1/T2 HCC had 1- and 5-year recurrence-free probabilities of 95.7% and 90.1%, respectively, versus 96.9% and 93.6%, respectively, for preoperative T3A stage (p = 0.58). Under-staging was observed in 20% of T2 and 29% of T3A HCC (p = 0.26). When explant tumor exceeded UCSF criteria (15%), the 1- and 5-year recurrence-free probabilities were 80.4% and 59.5%, versus 98.6% and 96.7%, respectively, for those within UCSF criteria (p < 0.0001). In conclusion, our results validated the ability of the UCSF criteria to discriminate prognosis after OLT and to serve as selection criteria for OLT, with a similar risk of tumor recurrence and under-staging when compared to the Milan criteria.

A randomized trial of exercise and dietary counseling after liver transplantation

We report results of a randomized clinical trial of a combined intervention of exercise and dietary counseling (ExD) after orthotopic liver transplantation (OLT). Of the 151 patients randomized into ExD or usual care (UC), 119 completed testing 2, 6 and 12 months post-OLT. Testing included assessment of exercise capacity (VO(2peak)), quadricep muscle strength, body composition (DXA), nutritional intake (Block 95) and health-related quality of life (SF-36). The intervention consisted of individualized counseling and follow-up to home-based exercise and dietary modification. Repeated measure ANOVA was performed to determine differences over time between ExD and UC with a secondary analysis to determine differences over time between adherers (Adh), nonadherers (Nadh) to the intervention and UC. The ExD group showed greater increases in VO(2peak) (p = 0.036), and self-reported general health (p = 0.038) compared to UC. Both groups demonstrated increases in muscle strength, body weight, body fat and other SF-36 scale scores. Adherence to the intervention was 37% with positive trends in VO(2peak) and body composition observed in Adh compared to Nadh and UC. These data suggest improvements in exercise capacity and body composition are achieved with nutrition and exercise behavior modifications initiated early after OLT and with regular follow-up.

Report of a National Conference on Donation after cardiac death

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.

Posttransplantation growth in pediatric liver recipients

The aim of this retrospective analysis was to evaluate the growth of 96 pediatric liver transplant recipients from February 1988 to June 1999. Inclusion criteria were the following: age younger than 18 years, follow-up longer than 1 year, transplantation for a nontumor indication, and no retransplantation. Linear height and growth velocity SD scores were correlated to age, sex, indication for transplantation, immunosuppression, and graft type. Transplant recipients of all ages and indications and both sexes were growth retarded at transplantation. Recipients aged younger than 24 months showed growth within the first year to achieve a height distribution equal to that of an age-matched population. Posttransplantation growth inversely correlated with height standard score at transplantation. Children older than 2 years at transplantation established new growth curves, but remained growth retarded. As children approached the prepubertal growth acceleration, growth deficits frequently were erased. Transplant recipients with biliary atresia and alpha(1)-antitrypsin deficiency showed increased growth performance compared with those who underwent transplantation for chronic hepatitis or fulminant hepatic failure. Boys were less growth retarded at transplantation and showed improved posttransplantation growth performance versus girls. No correlation to immunosuppression or graft type was identified. We conclude that early transplantation of children who show growth retardation is optimal for restoration of growth potential, whereas delaying transplantation in older children impedes potential growth.

Mixed allogeneic chimerism as a reliable model for composite tissue allograft tolerance induction across major and minor histocompatibility barriers

BACKGROUND

Although prolonged composite tissue allograft (CTA) survival is achievable in animals using immunosuppressive drugs, long-term immunosuppression of CTAs in the clinical setting may be unacceptable for most patients. The purpose of this study was to develop a model for reliable CTA tolerance induction in the adult rat across a major MHC mismatch without the need for long-term immunosuppression.

METHODS

Mixed allogeneic chimeras were prepared by using rat strains with strong MHC incompatibility [WF (RT1Au), ACI (RT1Aa)] WF + ACI-->WF, n=23. The bone marrow (BM) of recipient animals was pretreated with low-dose irradiation (500-700 cGy), followed by reconstitution with a mixture of T cell-depleted syngeneic (WF) and allogeneic (ACI) cells. Additionally, the recipient animals received a single dose of anti-lymphocyte serum (10 mg) 5 days before bone marrow transplantation (BMT) and tacrolimus (1 mg/kg/day) from the day before BMT to 10 days post-BMT. Hindlimb transplants were performed 12 months after BMT. Five animals received a limb allograft irradiated (1000 cGy) just before transplantation. Rat chimeras were characterized (percentage of donor cells present within the bloodstream) by flow cytometry at 3 and 12 months after BM reconstitution and after hindlimb transplantation.

RESULTS

Peripheral blood lymphocyte chimerism (WF/ACI) remained stable >12 months after BM reconstitution in 18/23 animals. Multi-lineage chimerism of both lymphoid and myeloid lineages was present, suggesting that engraftment of the pluripotent rat stem cell had occurred. In animals with donor chimerism >60% (n=18) no sign of limb rejection was present for the duration of the study. All animals with chimerism <20% (n=5) developed moderate signs of rejection clinically and histologically. Gross motor and sensory reinnervation (weight bearing, toe spread) developed at >60 days in 14/21 rats. Postoperative flow cytometry studies demonstrated stable chimerism in all animals studied (n=10). Five out of five animals with irradiated limb transplants showed no sign of GVHD at >100 days.

CONCLUSIONS

Stable mixed allogeneic chimerism can be achieved in a rat hindlimb model of composite tissue allotransplantation. Hindlimb allografts to mixed allogeneic chimeras exhibit prolonged, rejection-free survival. Partial functional return should be expected. The BM transplanted as part of the hindlimb allograft plays a role in the etiology of GVHD. Manipulating that BM before transplantation may influence the incidence of GVHD. This represents the first reliable rat hindlimb model demonstrating rejection-free CTA survival in an adult animal across a major MHC mismatch without the long-term need for immunosuppressive agents.

Liver transplantation for hepatocellular carcinoma: expansion of the tumor size limits does not adversely impact survival

The precise staging of hepatocellular carcinoma (HCC) based on the size and number of lesions that predict recurrence after orthotopic liver transplantation (OLT) has not been clearly established. We therefore analyzed the outcome of 70 consecutive patients with cirrhosis and HCC who underwent OLT over a 12-year period at our institution. Pathologic tumor staging of the explanted liver was based on the American Tumor Study Group modified Tumor-Node-Metastases (TNM) Staging Classification. Tumor recurrence occurred in 11.4% of patients after OLT. The Kaplan-Meier survival rates at 1 and 5 years were 91.3% and 72.4%, respectively, for patients with pT1 or pT2 HCC; and 82.4% and 74.1%, respectively, for pT3 tumors (P =.87). Patients with pT4 tumors, however, had a significantly worse 1-year survival of 33.3% (P =.0001). An alpha-fetoprotein (AFP) level > 1,000 ng/mL, total tumor diameter > 8 cm, age > or = 55 years and poorly differentiated histologic grade were also significant predictors for reduced survival in univariate analysis. Only pT4 stage and total tumor diameter remained statistically significant in multivariate analysis. Patients with HCC meeting the following criteria: solitary tumor < or = 6.5 cm, or < or = 3 nodules with the largest lesion < or = 4.5 cm and total tumor diameter < or = 8 cm, had survival rates of 90% and 75.2%, at 1 and 5 years, respectively, after OLT versus a 50% 1-year survival for patients with tumors exceeding these limits (P =.0005). We conclude that the current criteria for OLT based on tumor size may be modestly expanded while still preserving excellent survival after OLT.

Physical activity and health-related quality of life in liver transplant recipients

The US Surgeon General's Report on Physical Activity and Health recommends that people of all ages engage in regular physical activity, and that significant health benefits can be obtained through a moderate amount of physical activity. Physical activity appears to improve health-related quality of life (HRQOL) by enhancing physical functioning in persons compromised by poor health. The Medical Outcomes Study Short Form-36 (SF-36) Health Status Questionnaire was sent to all patients who were 5 years or more post-liver transplantation at the University of California at San Francisco. Additional questions related to coexisting medical conditions and participation in regular physical activity were included. SF-36 scale scores were compared between active and inactive patients. Regression analysis was also performed to determine the contributions of coexisting medical conditions and physical activity to the physical scales of the SF-36 questionnaire. Patients who participated in regular physical activity had significantly higher scores on all physical scales and the physical component scale (PCS). The regression model, which included age, sex, time posttransplantation, retransplantation, recurrence of hepatitis C, number of comorbid conditions, and physical activity participation showed that both the number of comorbid conditions and participation in physical activity were significant independent contributors to the physical functioning scale and PCS. This study indicates that physical activity is related to HRQOL after liver transplantation independent of other coexisting medical conditions.

Posttransplantation lymphoproliferative disorders in pediatric patients undergoing liver transplantation

OBJECTIVES

To study the clinicopathologic and molecular genetic findings in posttransplantation lymphoproliferative disorders (PTLDs) following pediatric liver transplantation and to determine the applicability of a recently proposed consensus classification system.

DESIGN

The clinical, pathologic, and molecular genetic findings of 11 PTLDs that occurred in 10 patients are presented. These 10 patients were derived from a group of 121 pediatric patients who underwent liver transplantation at the University of California, San Francisco. The PTLDs were classified using the proposed Society for Hematopathology scheme. Clonality was determined by immunohistochemical detection of monotypic immunoglobulin or by using polymerase chain reaction-based methods to detect monoclonal immunoglobulin heavy-chain gene rearrangements. Epstein-Barr virus (EBV) was detected by immunohistochemistry, in situ hybridization, or polymerase chain reaction. Epstein-Barr virus typing and the presence of LMP1 gene deletions were also analyzed by polymerase chain reaction.

RESULTS

There were 3 early lesions, 4 polymorphic PTLDs, and 4 monomorphic PTLDs. Monoclonality was demonstrated in 8 of 9 cases assessed. Epstein-Barr virus was present in all cases; of 9 cases assessed by polymerase chain reaction, the virus was type A in 8 and type B in 1. No EBV LMP1 gene deletions were identified. The corresponding liver explants were negative for EBV in 8 cases and positive in 1 case. Greater than 3 foci of disease and monomorphic PTLD were associated with decreased actuarial survival (P <.05).

CONCLUSIONS

The prognosis of pediatric patients with PTLD is favorable for early lesions and polymorphous PTLD, particularly in patients with localized disease. Multifocal disease and monomorphic PTLD are associated with an unfavorable prognosis.

A calcineurin inhibitor-sparing regimen with sirolimus, mycophenolate mofetil, and anti-CD25 mAb provides effective immunosuppression in kidney transplant recipients with delayed or impaired graft function

Delayed graft function (DGF) after renal transplantation is a significant risk factor for early acute rejection and graft loss. Sirolimus (SRL) can be administered in the setting of DGF without exacerbating the impaired renal function after transplantation. We examined a calcineurin-sparing regimen using SRL during the early post-operative period in renal transplant patients with delayed or impaired graft function. A retrospective review of 14 consecutive kidney transplant recipients with delayed or impaired graft function who received SRL was performed. The immunosuppressive regimen consisted of daclizumab induction (2 mg/kg), SRL (5-15 mg load followed by 2 5 mg daily maintenance therapy), corticosteroids, and mycophenolate mofetil (MMF, 1.5-3 g/d). Patients were monitored for allograft function, acute rejection, graft survival, thrombocytopenia, and leukopenia. Serum levels of SRL were determined by high-performance liquid chromatography performed at an independent commercial laboratory. Donors were cadaveric in 13 cases and living related in one. The duration of follow-up was 0.5-5.2 months. Nine patients required hemodialysis after transplantation. The mean time to initiation of calcineurin inhibitors was 21 +/- 13 d. Average serum creatinine levels at the initiation of SRL and at 1 month after transplantation were 8.4 +/- 2.7 and 2.1 +/- 1.2 mg/dL, respectively. There were 2 patients (14%) who experienced acute rejection within the first month after transplantation -1 with type I (steroid therapy) and 1 with type II (anti-thymocyte therapy). Serum levels of SRL were initially undetectable in the 2 patients with acute rejection. No grafts were lost during the period of follow-up. Three patients developed thrombocytopenia (platelets < 100 x 10(9)) and no patients developed leukopenia. The combination of SRL with anti-CD25 mAb, MMF, and corticosteroids appears to provide effective non-nephrotoxic immunosuppression for kidney transplantation without the need for a lymphocyte-depleting regimen. However, it is important to monitor serum SRL levels to determine the optimal dosing regimen. Furthermore, long-term follow-up of these patients will be helpful to determine whether improved immunosuppression can be achieved with a fully calcineurin-sparing regimen using SRL.

Surgical anatomy of the left lateral segment as applied to living-donor and split-liver transplantation: a clinicopathologic study

OBJECTIVE

To evaluate intrahepatic vascular and biliary anatomy of the left lateral segment (LLS) as applied to living-donor and split-liver transplantation.

SUMMARY BACKGROUND DATA

Living-donor and split-liver transplantation are innovative surgical techniques that have expanded the donor pool. Fundamental to the application of these techniques is an understanding of intrahepatic vascular and biliary anatomy.

METHODS

Pathologic data obtained from cadaveric liver corrosion casts and liver dissections were clinically correlated with the anatomical findings obtained during split-liver, living-donor, and reduced-liver transplants.

RESULTS

The anatomical relation of the left bile duct system with respect to the left portal venous system was constant, with the left bile duct superior to the extrahepatic transverse portion of the left portal vein. Four specific patterns of left biliary anatomy and three patterns of left hepatic venous drainage were identified and described.

CONCLUSIONS

Although highly variable, the biliary and hepatic venous anatomy of the LLS can be broadly categorized into distinct patterns. The identification of the LLS duct origin lateral to the umbilical fissure in segment 4 in 50% of cast specimens is significant in the performance of split-liver and living-donor transplantation, because dissection of the graft pedicle at the level of the round ligament will result in separate ducts from segments 2 and 3 in most patients, with the further possibility of an anterior segment 4 duct. A connective tissue bile duct plate, which can be clinically identified, is described to guide dissection of the segment 2 and 3 biliary radicles.

Experience with the use of sirolimus in liver transplantation--use in patients for whom calcineurin inhibitors are contraindicated

Sirolimus (SRL) provides effective immunosuppression for kidney transplantation and may be useful in patients with delayed allograft function after kidney transplantation. We review our experience with SRL in liver transplant recipients for whom calcineurin inhibitors are undesirable. Fourteen patients with renal insufficiency or acute mental status impairment were administered SRL after liver transplantation (5- to 10-mg load, 1 to 4 mg/d). Immunosuppression also consisted of mycophenolate mofetil and corticosteroids. On resolution of neurological or renal dysfunction (return to baseline mental status or serum creatinine level), tacrolimus (TAC) therapy was initiated. Twelve patients received primary transplants, 1 patient received a combined liver-kidney transplant, and 1 patient received a third transplant. Follow-up was 2 to 7 months. Calcineurin inhibitors were initially withheld in 9 patients, and therapy was aborted because of toxicity in the remaining 5 patients. Mean times to the initiation of SRL and TAC therapy were 5.4 +/- 4.6 and 26.8 +/- 24.4 days, respectively. Serum trough levels of SRL did not correlate with dose or other patient variables. Two patients died after prolonged pretransplantation hospital courses in the intensive care unit. Six patients experienced acute rejection, but only 1 patient required antilymphocyte therapy. Serum creatinine levels at the start of SRL therapy were 2.2 +/- 1.1 and 1.2 +/- 0.6 mg/dL at 3 months. All 3 patients with neurological indications for SRL had a return to their baseline mental status. All patients had improved liver function chemistry test results and prothrombin times. No patients developed leukopenia or thrombocytopenia. SRL is safe after liver transplantation in patients with acute neurological or renal impairment. SRL is an attractive alternative when calcineurin inhibitors are undesirable, but serum trough levels of SRL should be monitored. A prospective randomized study of an SRL-based calcineurin inhibitor-avoiding regimen compared with standard therapy in patients with renal insufficiency will further evaluate the role for SRL in liver transplantation.

Prolonged cold ischemia time obviates the benefits of 0 HLA mismatches in renal transplantation

HYPOTHESIS

Recipients of 0 HLA mismatch kidneys with prolonged cold ischemia times of longer than 36 hours do not have superior outcomes compared with recipients of kidneys with 1 or more mismatches.

DESIGN

Retrospective review.

SETTING

Transplanation centers.

PATIENTS AND METHODS

A total of 63,688 recipients who underwent transplantation between January 1, 1990, and July 31, 1998.

MAIN OUTCOME MEASURES

Delayed graft function, serum creatinine level, and patient and renal graft survival.

RESULTS

Recipients of 0 HLA mismatch kidneys with fewer than 36 hours of cold ischemia time had better 5-year graft survival (75%) when compared with recipients with 1 or more mismatches (67%) (P<.001). However, recipients of 0 HLA mismatch kidneys with longer than 36 hours of cold ischemia time did not have any graft survival advantage (71% in 0 HLA mismatch kidneys vs 72% in 1 or more mismatches, P =.24).

CONCLUSIONS

Cold ischemia times of longer than 36 hours obviate the benefits of better graft survival conferred by better matching.

A non-cleavable mutant of Fas ligand does not prevent neutrophilic destruction of islet transplants

BACKGROUND

Fas ligand (FasL) mediates apoptosis of susceptible Fas-expressing lymphocytes, and may contribute to the maintenance of peripheral tolerance. In transplantation models, however, artificial expression of FasL on cellular as well as islet transplants results in accelerated rejection by neutrophils. The mechanism of the neutrophilic response to FasL expression is unknown. FasL, like other members of the tumor necrosis factor family, is cleaved to a soluble form by metalloproteases. We tested the hypothesis that soluble FasL (sFasL) was responsible for neutrophil migration by creating a non-cleavable mutant of FasL.

METHODS

Three mutants of FasL with serial deletions in the putative proteolytic cleavage site of human FasL were made using inverse polymerase chain reaction. The relative fractions of sFasL and membrane-bound FasL were assessed by Western blot and immunoprecipitation, as well as by cytotoxicity assay using Fas-expressing target cells. The fully non-cleavable mutant was transduced into murine islets as well as myoblasts and tumor cell lines, and tested in a murine transplantation model.

RESULTS

Serial deletions in the putative metalloprotease site of FasL resulted in a fully non-cleavable mutant of FasL (ncFasL). Expression of ncFasL in tumor lines induced higher levels of apoptosis in Fas bearing targets than wild-type FasL. Transplantation of ncFasL-expressing islets under the kidney capsule of allogenic mice resulted in accelerated rejection identical to that seen with wild-type Fas ligand-expressing islets. Myoblasts and tumor cell lines expressing ncFasL also induced neutrophil infiltration.

CONCLUSIONS

Membrane-bound Fas ligand is fully capable of inducing a neutrophilic response to transplants, suggesting an activation by Fas ligand of neutrophil chemotactic factors.

A dendritic cell line genetically modified to express CTLA4-IG as a means to prolong islet allograft survival

BACKGROUND

Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response.

METHOD

A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc].

RESULT

Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment.

CONCLUSIONS

These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.

Flow cytometry crossmatching as a predictor of acute rejection in sensitized recipients of cadaveric renal transplants

Flow cytometry crossmatching (FCXM) was developed as a more sensitive assay than the standard complement-dependent cytotoxicity crossmatch (CDCXM) for the detection of anti-donor antibodies, that mediate hyperacute rejection and graft loss in the early post-transplant period in renal transplant recipients. The role of FCXM in predicting long-term clinical outcome in renal allograft recipients is unclear. This study examines the role of FCXM in predicting long-term clinical outcome in highly sensitized recipients of cadaveric renal transplants. All patients (n = 100) with peak panel reactive antibody (PRA) levels > 30%, who received cadaveric renal transplants between 1/1/'90 and 12/31/'95 at our institution, were divided into FCXM + and FCXM - groups. The incidence of acute rejection was determined for each group during the first yr after transplant. Graft survival rates at 1, 2, and 3 yr, and creatinine levels were also compared between groups. FCXM + patients experienced a higher incidence of acute rejection during the first yr after transplant (69 vs. 45%), and a higher percentage of FCXM + patients had more than one episode of acute rejection during the first yr after transplant (34 vs. 8%) when compared to FCXM - patients. There was no statistically significant difference in 1-, 2-, or 3-yr graft survival between FCXM + and FCXM - patients (76 vs. 83, 62 vs. 80, 62 vs. 72%, respectively). These results suggest that sensitized FCXM + cadaveric renal transplant recipients have a higher incidence of acute rejection episodes in the first yr after transplant. Given the association of multiple rejection episodes with poor long-term allograft survival, FCXM may be a useful predictor of long-term clinical outcome in this sub-group of renal transplant recipients.

Experience with daclizumab in liver transplantation: renal transplant dosing without calcineurin inhibitors is insufficient to prevent acute rejection in liver transplantation

BACKGROUND

Daclizumab is a monoclonal antibody directed against the alpha chain of the interleukin 2 receptor. We review our experience with the use of daclizumab in liver transplant recipients.

METHODS

Thirty-two patients were given daclizumab as induction therapy in the setting of hepatic transplantation. Seven of these patients were enrolled in a pilot study to determine the efficacy of daclizumab in conjunction with corticosteroids and mycophenolate mofetil without the initial use of calcineurin inhibitors (CI). The remaining 25 patients received daclizumab, mycophenolate mofetil, and steroids, with the institution of CI generally within the first postoperative week. The majority of these patients (n = 17) had some degree of renal insufficiency.

RESULTS

The pilot study was halted after the first seven patients were enrolled because of an unacceptably high rate of rejection (7/7 = 100%). The patients outside of this pilot study, however, had a much lower rate of rejection (36%). The incidence and severity of rejection correlated with the delay in institution of CI. The described dosing schedule resulted in subtherapeutic daclizumab levels in liver transplant recipients.

CONCLUSIONS

Daclizumab used in liver transplant recipients without any CI was ineffective and can potentially lead to steroid-resistant rejection. The dosing regimen used in renal transplant recipients is most likely insufficient for liver transplant patients. However, daclizumab can be used safely in patients with preexisting or postoperative renal dysfunction in conjunction with low doses of CI given within the first week postoperatively.

Four-year follow-up of mycophenolate mofetil for graft rescue in liver allograft recipients

BACKGROUND

Mycophenolate mofetil (MMF) has been shown to have promise in short-term liver transplantation graft rescue studies. The purpose of this study was to evaluate the long-term efficacy and safety of MMF in liver transplant patients who had failed cyclosporine (CsA)-based conventional immunosuppression.

METHODS

Nineteen orthotopic liver allograft recipients were converted from azathioprine to MMF in combination with CsA and prednisone in this prospective, open-labeled, single-center, graft rescue, pilot study. Six patients were taken off CsA when MMF was initiated. A 4-year patient follow-up is reported here. Patients were considered to have failed CsA-based immunosuppression either for refractory rejection, chronic rejection, or severe CsA neurologic toxicity.

RESULTS

Twelve patients had complete histologic resolution, two had partial resolution, and three had worsening of their rejection. Thirteen patients had a complete biochemical response; one had a partial response and four had worsening of their rejection. Two patients had no histologic and one no biochemical follow-up. Of the six patients treated with MMF and prednisone alone, four had complete resolution of rejection without recurrence. The majority of adverse reactions were gastrointestinal [nausea and/or vomiting (n=5); diarrhea (n=8); gastritis, duodenitis, or esophagitis (n=4); and ulcers (n=2)] or bone marrow suppressive [leukopenia (n=9), anemia (n=6), and thrombocytopenia (n=5)].

CONCLUSIONS

MMF seems to be an effective alternative immunosuppressive in patients failing CsA-based conventional therapy. MMF may be of particular benefit in patients who do not tolerate CsA or tacrolimus. The long-term safety profile is similar to that of other immunosuppressives.

Mycophenolate mofetil, microemulsion cyclosporine, and prednisone as primary immunosuppression for pediatric liver transplant recipients

Triple immunosuppressive therapy using mycophenolate mofetil (MMF), microemulsion cyclosporine (me-CsA), and prednisone offers the potential for potent immunosuppression without intravenous drug therapy or anti-T-cell antibody induction therapy. This report describes the application of an immunosuppressive protocol (CNp) using MMF, me-CsA, and prednisone as primary immunosuppression for pediatric liver transplant recipients at the University of California at San Francisco. From August 1995 through December 1996, 26 children (17 boys, 9 girls) aged 1 month to 16 years (mean +/- standard deviation, 58 +/- 62 months; median, 31 months) underwent liver transplantation at our institution, receiving CNp as primary immunosuppression. Posttransplantation renal function, incidence of leukopenia, and drug tolerance within the group receiving CNp as primary immunosuppression were compared with those of 19 children who received primary immunosuppression consisting of azathioprine, oil-based gel-encapsulated cyclosporine, and prednisone with anti-T-cell antibody induction therapy at the same institution from October 1993 through July 1995. No significant difference was observed between immunosuppressive protocols in serum creatinine level or incidence of leukopenia requiring medical therapy during the first year posttransplantation. Whereas gastrointestinal symptoms were observed in approximately 30% of CNp recipients during initial immunotherapy, tolerance of CNp primary immunotherapy was routinely achieved by the dose reduction of MMF. At 1 year posttransplantation, 20 children (77%) remained on CNp primary immunotherapy, 5 children (19%) were receiving tacrolimus-based immunotherapy secondary to rejection, and 1 patient (4%) converted to tacrolimus-based immunotherapy secondary to persistent gastrointestinal intolerance. In conclusion, CNp provides an alternative immunosuppressive protocol that eliminates the necessity of intravenous and induction immunosuppressive therapy with no increased incidence of posttransplantation renal dysfunction or leukopenia and is well tolerated in children.