Evaluation of the effect of tofacitinib exposure on outcomes in kidney transplant patients

Tofacitinib fixed-dose regimens attained better kidney function and comparable efficacy to cyclosporine (CsA) in kidney transplant patients, albeit with increased risks of certain adverse events. This post-hoc analysis evaluated whether a patient subgroup with an acceptable risk-benefit profile could be identified. Tofacitinib exposure was a statistically significant predictor of serious infection rate. One-hundred and eighty six kidney transplant patients were re-categorized to above-median (AME) or below-median (BME) exposure groups. The 6-month biopsy-proven acute rejection rates in AME, BME and CsA groups were 7.8%, 15.7% and 17.7%, respectively. Measured glomerular filtration rate was higher in AME and BME groups versus CsA (61.2 and 67.9 vs. 53.9 mL/min) at Month 12. Fewer patients developed interstitial fibrosis and tubular atrophy (IF/TA) at Month 12 in AME (20.5%) and BME (27.8%) groups versus CsA (48.3%). Serious infections occurred more frequently in the AME group (53.0%) than in BME (28.4%) or CsA (25.5%) groups. Posttransplant lymphoproliferative disorder (PTLD) only occurred in the AME group. In kidney transplant patients, the BME group preserved the clinical advantage of comparable acute rejection rates, improved renal function and a lower incidence of IF/TA versus CsA, and with similar rates of serious infection and no PTLD.

Chimerism, graft survival, and withdrawal of immunosuppressive drugs in HLA matched and mismatched patients after living donor kidney and hematopoietic cell transplantation

Thirty-eight HLA matched and mismatched patients given combined living donor kidney and enriched CD34(+) hematopoietic cell transplants were enrolled in tolerance protocols using posttransplant conditioning with total lymphoid irradiation and anti-thymocyte globulin. Persistent chimerism for at least 6 months was associated with successful complete withdrawal of immunosuppressive drugs in 16 of 22 matched patients without rejection episodes or kidney disease recurrence with up to 5 years follow up thereafter. One patient is in the midst of withdrawal and five are on maintenance drugs. Persistent mixed chimerism was achieved in some haplotype matched patients for at least 12 months by increasing the dose of T cells and CD34(+) cells infused as compared to matched recipients in a dose escalation study. Success of drug withdrawal in chimeric mismatched patients remains to be determined. None of the 38 patients had kidney graft loss or graft versus host disease with up to 14 years of observation. In conclusion, complete immunosuppressive drug withdrawal could be achieved thus far with the tolerance induction regimen in HLA matched patients with uniform long-term graft survival in all patients.

Desensitization combined with paired exchange leads to successful transplantation in highly sensitized kidney transplant recipients: strategy and report of five cases

Sensitization remains a major barrier to kidney transplantation. Sensitized patients comprise 30% of the kidney transplant waiting list but fewer than 15% of highly sensitized patients are transplanted each year. Options for highly sensitized patients with an immunologically incompatible living donor include desensitization or kidney paired donation (KPD). However, these options when used alone may still not be sufficient to allow a compatible transplant for recipients who are broadly sensitized with cumulative calculated panel-reactive antibody (cPRA) > 95%. We describe in this report the combined use of both desensitization and KPD to maximize the likelihood of finding a compatible match with a more immunologically favorable donor through a kidney exchange program. This combined approach was used in five very highly sensitized patients, all with cPRA 100%, who ultimately received compatible living and deceased donor kidney transplants. We conclude that early enrollment in paired kidney donor exchange and tailored desensitization protocols are key strategies to improve care and rates of kidney transplantation in highly sensitized patients.

Randomized phase 2b trial of tofacitinib (CP-690,550) in de novo kidney transplant patients: efficacy, renal function and safety at 1 year

In this Phase 2b study, 331 low-to-moderate risk de novo kidney transplant patients (approximately 60% deceased donors) were randomized to a more intensive (MI) or less intensive (LI) regimen of tofacitinib (CP-690, 550), an oral Janus kinase inhibitor or cyclosporine (CsA). All patients received basiliximab induction, mycophenolic acid and corticosteroids. Primary endpoints were: incidence of biopsy-proven acute rejection (BPAR) with a serum creatinine increase of ≥0.3 mg/dL and ≥20% (clinical BPAR) at Month 6 and measured GFR at Month 12. Similar 6-month incidences of clinical BPAR (11%, 7% and 9%) were observed for MI, LI and CsA. Measured GFRs were higher (p < 0.01) at Month 12 for MI and LI versus CsA (65 mL/min, 65 mL/min vs. 54 mL/min). Fewer (p < 0.05) patients in MI or LI developed chronic allograft nephropathy at Month 12 compared with CsA (25%, 24% vs. 48%). Serious infections developed in 45%, 37% and 25% of patients in MI, LI and CsA, respectively. Anemia, neutropenia and posttransplant lymphoproliferative disorder occurred more frequently in MI and LI compared with CsA. Tofacitinib was equivalent to CsA in preventing acute rejection, was associated with improved renal function and less chronic allograft histological injury, but had side-effects at the doses evaluated.

Chain transplantation: initial experience of a large multicenter program

We report the results of a large series of chain transplantations that were facilitated by a multicenter US database in which 57 centers pooled incompatible donor/recipient pairs. Chains, initiated by nondirected donors, were identified using a computer algorithm incorporating virtual cross-matches and potential to extend chains. The first 54 chains facilitated 272 kidney transplants (mean chain length = 5.0). Seven chains ended because potential donors became unavailable to donate after their recipient received a kidney; however, every recipient whose intended donor donated was transplanted. The remaining 47 chains were eventually closed by having the last donor donate to the waiting list. Of the 272 chain recipients 46% were ethnic minorities and 63% of grafts were shipped from other centers. The number of blood type O-patients receiving a transplant (n = 90) was greater than the number of blood type O-non-directed donors (n = 32) initiating chains. We have 1-year follow up on the first 100 transplants. The mean 1-year creatinine of the first 100 transplants from this series was 1.3 mg/dL. Chain transplantation enables many recipients with immunologically incompatible donors to be transplanted with high quality grafts.

The PROMISE study: a phase 2b multicenter study of voclosporin (ISA247) versus tacrolimus in de novo kidney transplantation

Voclosporin (VCS, ISA247) is a novel calcineurin inhibitor being developed for organ transplantation. PROMISE was a 6-month, multicenter, randomized, open-label study of three ascending concentration-controlled groups of VCS (low, medium and high) compared to tacrolimus (TAC) in 334 low-risk renal transplant recipients. The primary endpoint was demonstration of noninferiority of biopsy proven acute rejection (BPAR) rates. Secondary objectives included renal function, new onset diabetes after transplantation (NODAT), hypertension, hyperlipidemia and pharmacokinetic-pharmacodynamic evaluation. The incidence of BPAR in the VCS groups (10.7%, 9.1% and 2.3%, respectively) was noninferior to TAC (5.8%). The incidence of NODAT for VCS was 1.6%, 5.7% and 17.7% versus 16.4% in TAC (low-dose VCS, p = 0.03). Nankivell estimated glomerular filtration rate was respectively: 71, 72, 68 and 69 mL/min, statistically lower in the high-dose group, p = 0.049. The incidence of hypertension and adverse events was not different between the VCS groups and TAC. VCS demonstrated an excellent correlation between trough and area under the curve (r(2) = 0.97) and no difference in mycophenolic acid exposure compared to TAC. This 6-month study shows VCS to be as efficacious as TAC in preventing acute rejection with similar renal function in the low- and medium-exposure groups, and potentially associated with a reduced incidence of NODAT.

Managing finances of shipping living donor kidneys for donor exchanges

Kidney donor exchanges enable recipients with immunologically incompatible donors to receive compatible living donor grafts; however, the financial management of these exchanges, especially when an organ is shipped, is complex and thus has the potential to impede the broader implementation of donor exchange programs. Representatives from transplant centers that utilize the National Kidney Registry database to facilitate donor exchange transplants developed a financial model applicable to paired donor exchanges and donor chain transplants. The first tenet of the model is to eliminate financial liability to the donor. Thereafter, it accounts for the donor evaluation, donor nephrectomy hospital costs, donor nephrectomy physician fees, organ transport, donor complications and recipient inpatient services. Billing between hospitals is based on Medicare cost report defined costs rather than charges. We believe that this model complies with current federal regulations and effectively captures costs of the donor and recipient services. It could be considered as a financial paradigm for the United Network for Organ Sharing managed donor exchange program.

Asynchronous, out-of-sequence, transcontinental chain kidney transplantation: a novel concept

The organ donor shortage has been the most important hindrance in getting listed patients transplanted. Living kidney donors who are incompatible with their intended recipients are an untapped resource for expanding the donor pool through participation in transplant exchanges. Chain transplantation takes this concept further, with the potential to benefit even more recipients. We describe the first asynchronous, out of sequence transplant chain that was initiated by transcontinental shipment of an altruistic donor kidney 1 week after that recipient's incompatible donor had already donated his kidney to the next recipient in the chain. The altruistic donor kidney was transported from New York to Los Angeles and functioned immediately after transplantation. Our modified-sequence asynchronous transplant chain (MATCH) enabled eight recipients, at four different institutions, to benefit from the generosity of one altruistic donor and warrants further exploration as a promising step toward addressing the organ donor shortage.

Calcineurin-inhibitor-free immunosuppression based on the JAK inhibitor CP-690,550: a pilot study in de novo kidney allograft recipients

This randomized, pilot study compared the Janus kinase inhibitor CP-690,550 (15 mg BID [CP15] and 30 mg BID [CP30], n = 20 each) with tacrolimus (n = 21) in de novo kidney allograft recipients. Patients received an IL-2 receptor antagonist, concomitant mycophenolate mofetil (MMF) and corticosteroids. CP-690,550 doses were reduced after 6 months. Due to a high incidence of BK virus nephropathy (BKN) in CP30, MMF was discontinued in this group. The 6-month biopsy-proven acute rejection rates were 1 of 20, 4 of 20 and 1 of 21 for CP15, CP30 and tacrolimus groups, respectively. BKN developed in 4 of 20 patients in CP30 group. The 6-month rates of cytomegalovirus disease were 2 of 20, 4 of 20 and none of 21 for CP15, CP30 and tacrolimus groups, respectively. Estimated glomerular filtration rate was >70 mL/min at 6 and 12 months (all groups). NK cells were reduced by </=77% in CP-690,550-treated patients. In the CP-690,550 arms, there were modest lipid elevations and a trend toward more frequent anemia and neutropenia during the first 6 months. These data suggest that coadministration of CP-690,550 30 mg BID with MMF is associated with overimmunosuppression. At 15 mg BID, the efficacy/safety profile was comparable to the tacrolimus control group, excepting a higher rate of viral infection. Further dose-ranging evaluation of CP-690,550 is warranted.

Calcineurin-inhibitor-free immunosuppression based on the JAK inhibitor CP-690,550: a pilot study in de novo kidney allograft recipients

This randomized, pilot study compared the Janus kinase inhibitor CP-690,550 (15 mg BID [CP15] and 30 mg BID [CP30], n = 20 each) with tacrolimus (n = 21) in de novo kidney allograft recipients. Patients received an IL-2 receptor antagonist, concomitant mycophenolate mofetil (MMF) and corticosteroids. CP-690,550 doses were reduced after 6 months. Due to a high incidence of BK virus nephropathy (BKN) in CP30, MMF was discontinued in this group. The 6-month biopsy-proven acute rejection rates were 1 of 20, 4 of 20 and 1 of 21 for CP15, CP30 and tacrolimus groups, respectively. BKN developed in 4 of 20 patients in CP30 group. The 6-month rates of cytomegalovirus disease were 2 of 20, 4 of 20 and none of 21 for CP15, CP30 and tacrolimus groups, respectively. Estimated glomerular filtration rate was >70 mL/min at 6 and 12 months (all groups). NK cells were reduced by </=77% in CP-690,550-treated patients. In the CP-690,550 arms, there were modest lipid elevations and a trend toward more frequent anemia and neutropenia during the first 6 months. These data suggest that coadministration of CP-690,550 30 mg BID with MMF is associated with overimmunosuppression. At 15 mg BID, the efficacy/safety profile was comparable to the tacrolimus control group, excepting a higher rate of viral infection. Further dose-ranging evaluation of CP-690,550 is warranted.

Lack of benefit of early protocol biopsies in renal transplant patients receiving TAC and MMF: a randomized study

We conducted a randomized, multicenter study to determine whether treatment of subclinical rejection with increased corticosteroids resulted in beneficial outcomes in renal transplant patients receiving tacrolimus (TAC), mycophenolate mofetil (MMF) and prednisone. One hundred and twenty-one patients were randomized to biopsies at 0,1,2,3 and 6 months (Biopsy arm), and 119 to biopsies at 0 and 6 months only (Control arm). The primary endpoint of the study was the prevalence of the sum of the interstitial and tubular scores (ci + ct)> 2 (Banff) at 6 months. Secondary endpoints included clinical and subclinical rejection and renal function. At 6 months, 34.8% of the Biopsy and 20.5% of the Control arm patients had a ci + ct score >or= 2 (p = 0.07). Between months 0 and 6, clinical rejection episodes were 12 in 10 Biopsy arm patients and 8 in 8 Control arm patients (p = 0.44). Overall prevalence of subclinical rejection in the Biopsy arm was 4.6%. Creatinine clearance at 6 months was 72.9 +/- 21.7 in the Biopsy and 68.90 mL/min +/- 18.35 mL/min in the Control arm patients (p = 0.18). In conclusion, we found no benefit to the procurement of early protocol biopsies in renal transplant patients receiving TAC, MMF and prednisone, at least in the short term. This is likely due to their low prevalence of subclinical rejection.

Circulating growth hormone binding protein levels and mononuclear cell growth hormone receptor expression in uremia

BACKGROUND

Resistance to growth hormone (GH) in end-stage renal disease (ESRD) causes growth retardation and muscle wasting. In humans, circulating GH binding protein (GHBP), the extracellular domain of the GH receptor that is shed into the circulation and is believed to reflect tissue GH receptor levels, is reduced in uremia and suggests that cellular GH receptor levels are correspondingly reduced. If true, this could be a cause of GH resistance. We set out to establish whether serum GHBP levels reflect cellular GH receptor levels and whether changes in serum GHBP levels are related to nutritional or inflammatory status.

METHODS

GH receptor protein expression in peripheral blood mononuclear cells (PBMC) from 21 ESRD and 14 normal subjects were analyzed by fluorochrome flow cytometry.

RESULTS

The GH receptor density and percent total PBMCs expressing the GH receptor were similar in the 2 groups, and there was no difference in percent GH receptor positive T or B cells or monocytes. In contrast, serum GHBP levels were 80% lower in ESRD. GHBP levels did not correlate with serum albumin, body mass index, or muscle mass but seemed to be partly related to the log serum C-reactive protein levels.

CONCLUSIONS

Serum GHBP levels are markedly reduced in ESRD; this seems to occur independent of nutritional status and may in part be caused by inflammation. Because GH receptor expression on PBMC of ESRD and control subjects was similar, our findings argue against a reduction in GH receptor as a cause of GH resistance and the use of serum GHBP levels as a reliable marker of specific tissue GH receptor levels.

Conversion of stable liver transplant recipients from a twice-daily Prograf-based regimen to a once-daily modified release tacrolimus-based regimen

INTRODUCTION

Modified release (MR) tacrolimus is an extended release formulation administered once daily. The purpose of this pharmacokinetic (PK) study was to evaluate tacrolimus exposure in stable liver transplant recipients converted from Prograf twice a day to MR tacrolimus once daily.

METHODS

This was an open-label, multicenter study with a single sequence, four-period crossover design. Eligible patients were 18 to 65 years of age, >6 months posttransplant with stable renal and hepatic function and receiving stable doses of Prograf twice a day for >2 weeks prior to enrollment. Patients received Prograf twice a day on days 1 to 14 and 29 to 42. Patients were converted to the same milligram-for-milligram daily dose of MR once daily on days 15 to 28 and 43 to 56. Twenty-four-hour PK profiles were obtained on days 14, 28, 42, and 56. Laboratory and safety parameters were also evaluated.

RESULTS

Of 70 patients, 62 completed all four PK profiles. The AUC0-24 of tacrolimus was comparable for Prograf twice a day (days 14 and 42) and MR tacrolimus once daily (days 28 and 56). The 90% confidence intervals for MR tacrolimus versus Prograf at steady state (days 28 and 56 vs days 14 and 42) was 0.85 to 0.92 for AUC0-24. MR tacrolimus was well tolerated with a safety profile comparable to that of Prograf. AUC0-24 was highly correlated to Cmin for Prograf (day 14, r = .93; Day 42, r = .89) and for MR tacrolimus (day 28, r = .93; day 56, r = .92). Renal and liver function remained stable. One patient experienced acute rejection.

CONCLUSION

The steady-state tacrolimus exposure of MR tacrolimus once daily is equivalent to Prograf twice a day after a milligram-for-milligram conversion in stable liver transplant recipients.

In vivo higher glucuronidation of mycophenolic acid in male than in female recipients of a cadaveric kidney allograft and under immunosuppressive therapy with mycophenolate mofetil

Mycophenolate mofetil (MMF), an immunosuppressant drug used in organ transplantation to prevent rejection, is being used increasingly in association with cyclosporine and tacrolimus. Mycophenolic acid (MPA) is primarily metabolized in the liver to its 7-O-glucuronide (MPAG) derivative. The concentrations of MPAG in serum are many times the concentrations of MPA. Although MPAG has not shown immunosuppressant activity, it was postulated that it could displace MPA from its binding sites on albumin and hence increase the biologic effects of MPA. This effect could be important for patients with acute renal failure; under this condition, MPAG was shown to accumulate. The goal of this study was to document the MPAG/MPA concentration ratio in 100 renal transplant patients under a mixed immunosuppressive therapy. Further, the study addressed the question of whether MPAG can displace MPA in vivo from bound albumin in a representative renal transplant patient population under immunosuppressive therapy. Levels of MPAG and MPA were measured by high-performance liquid chromatography. The distribution of the ratios was not parametric as it tailed toward elevated values. After a square root transformation of the data, parametric analysis was possible. The average MPAG/MPA ratio was 15.0 +/- 2.2 for men versus 7.7 +/- 0.9 for women. Men treated with MMF and tacrolimus showed a lower ratio than patients treated with MMF and cyclosporine, confirming that tacrolimus inhibits glucuronidation of MPA. Further, it was determined that at physiologic concentrations, MPAG does not increase the amount of free MPA. Because MPAG can favor the elimination of MPA, it can be concluded that gender differences and cotreatment with tacrolimus must be taken into consideration when MMF is being administered.

[Hypertrichosis and gingival hypertrophy regression in renal transplants following the substitution of cyclosporin by tacrolimus]

Gingival Hyperplasia (GH) and hypertrichosis (HT) are two sides effects associated with the usage of cyclosporine (CyA) but not with tacrolimus (FK 506). The aim of this study is to evaluate the efficacy and security of the conversion from CsA to FK 506 to treat those two complications. From August 1996 to May 1997, 15 patients (9 males, 6 females) aged from 23 to 63 years old (38 +/- 14, mean +/- SD) were switched from CsA to FK 506, 12 for GH, 2 for HT and one for combined presentation. FK 506 was first initiated at a dose of 0.15 mg/kg/day and then adjusted to a level target of 8 ng/ml. The conversion was done on an out patient basis at average 35 (5-83) months after transplantation. Patients were followed prospectively for 12 months. There was a significant reduction in GH in all patients within 3 months. Five out 13 patients had a complete resolution of GH within three months of conversion, 9/12 within 6 months and all by 12 months. HT resolved completely within 6 months. No rejection episode occurred and the serum creatinin remain stable over one year post conversion. Conversion from CsA to FK 506 is thus a safe and valid option to treat CsA induced GH and HT.

Effect of intraoperative blood transfusion on patient outcome in hepatic transplantation

OBJECTIVE

To evaluate the effect of intraoperative transfusion of red blood cells (RBCs) on patient and graft survival.

DESIGN

A retrospective study.

SETTING

A tertiary care referral center.

PATIENTS

Between January 1, 1992, and December 31, 1994, medical records from 225 adult patients who underwent primary liver transplantations were analyzed.

RESULTS

Overall patient survival was 90% at 1 year and 86% at 3 years, while graft survival was 89% at 1 year and 85% at 3 years. The following factors were associated with patient and graft survival: age, sex, medical condition at the time of transplantation, and intraoperative transfusion of RBCs. When these factors were subjected to a multivariate analysis, all were independently associated with survival. Fifty-four recipients (24%) underwent transplantation without intraoperative transfusion of RBCs, while 171 recipients (76%) received at least 1 U of RBCs intraoperatively. Recipients who did not receive transfusion of RBCs had higher patient and graft survival rates than patients who did receive RBCs. By multivariate analysis, transplantation without intraoperative transfusion of RBCs no longer remained statistically significant, and only sex and the patient's medical condition were independently associated with patient and graft survival. Patient and graft survival decreased if 5 or more U were transfused, but transfusion of 5 or more U was not independently associated with survival by multivariate analysis.

CONCLUSIONS

Increased transfusion requirement for RBCs was independently associated with patient and graft survival. While transplantation without transfusion of intraoperative RBCs was associated with superior patient and graft survival, these effects were overridden by patient sex and medical condition at the time of transplantation.

[Intrahepatic glutathione and oxidative stress in liver transplantation in the pig]

OBJECT

To determine the loss of endogenous GSH from livers cold-stored and reperfused, using a model of liver transplantation in the pig.

MATERIAL AND METHODS

Four female Yorkshire pigs weighing 19 to 40 kg received a liver allograft. Donor livers were cold-stored in the UW solution. Mean cold ischemic time was 6.5 hours. Malondialdehyde (MDA) levels were used as an index of oxidative stress. MDA plasma levels were measured following recipient laparotomy (H0), immediately (H1), and 90 minutes after liver reperfusion (H2). MDA and GSH levels in liver were measured following donor laparotomy (T0), at the end of cold ischemic period (T1), and at 90 minutes following liver reperfusion (T2).

RESULTS

Three animals survived. MDA liver levels decreased of 44% between T0 and T1, then increased to 92% at T2. In contrast, in plasma, graft reperfusion was associated with an increase of MDA to 140% of the baseline values which reached 188% at H2. Intrahepatic GSH levels decreased of 49% at T1, then to 72% at T2.

CONCLUSION

our study suggests that in liver transplantation: (1) Hepatic GSH is depleted to 49% during cold-storage, and an additional 23% is lost after reperfusion; (2) GSH contained in the UW solution does not prevent the loss of hepatocellular glutathione during preservation and reperfusion; (3) after short periods of cold ichemia, endogenous hepatic GSH may protect against oxydative stress in the transplanted liver.

Experience with the piggyback technique without caval occlusion in adult orthotopic liver transplantation

BACKGROUND

To assess the feasibility and outcome of a piggyback technique without caval occlusion or veno-venous bypass (VB), we retrospectively reviewed 131 consecutive adult orthotopic liver transplantation (OLT) performed in 129 patients between May 1993 and February 1995. Six were second transplants, and six were combined liver-kidney transplants. The piggyback technique was attempted in all cases.

METHODS

We were able to perform the piggyback technique in 98 OLTs (75%). The remaining 33 OLTs (25%) were converted to the standard technique; of these, 20 (15%) required VB. The reasons for conversion to the standard technique were: anatomical (22 transplants), severe portal hypertension requiring VB (8 transplants), tumor (1 transplant), and other reasons (2 transplants). Six retransplantations were performed (four piggyback, two standard).

RESULTS

There was no significant difference in age, United Network for Organ Sharing status, Child's classification, and diagnosis between the patients in whom piggyback was possible or not. The actuarial patient and graft survival at 1 year were similar between the piggyback group and the group of patients converted to standard technique (87/85% vs. 86/86%, respectively). No death was related to either technique. With piggyback, the average operative time was 8.6+/-1.9 hr, median amount of blood transfused intraoperatively was 2 U (33% did not require transfusion), and median intensive care unit and hospital stays were 3 and 11 days, respectively. With the piggyback technique, the mean preoperative and maximum postoperative serum creatinine levels were 1.4+/-1.0 and 1.8+/-1.5 mg/dl.

CONCLUSION

The piggyback technique without caval occlusion is possible in the majority of patients. It is safe and has reduced the use of VB to 15% of our adult OLTs. The piggyback technique avoids retrocaval dissection, facilitates retransplantation, and is associated with a short anhepatic phase, low blood product usage, and short intensive care unit stay.

Tacrolimus (FK506) and sirolimus (rapamycin) in combination are not antagonistic but produce extended graft survival in cardiac transplantation in the rat

Combined use of tacrolimus (FK506) with sirolimus (rapamycin [RAPA]) was examined in a model of vascularized heart allograft in the rat. For prevention of acute rejection, three different combinations of low doses of FK506 and RAPA from day 1 up to day 14 after transplantation produced significantly longer cardiac allograft survival than each agent alone (P<0.05). Identical results were observed in a model of reversal of ongoing acute rejection, where two combinations of low doses of FK506 and RAPA from day 4 up to day 18 after surgery also demonstrated significantly longer graft survival than each immunosuppressant alone (P<0.05). All the low-dose-treated groups in these two models presented significantly longer heart graft survival than naive controls (P<0.05), confirming that both agents are potent immunosuppressants in the models chosen. These results also indicate that, in contrast with in vitro studies, the combined use of FK506 and RAPA in vivo did not produce antagonism, but rather had synergistic effect in prolonging the allograft survival as compared with each agent alone. It appears likely that the abundance of FKBP-12 available for binding in vivo prevents inhibitive competition of the two agents for their receptor.

Left hepaticogastrostomy for biliary obstruction: long-term results

PURPOSE

To evaluate the long-term results of peripheral biliary diversion by means of anastomoses of the left lobe of the liver to the stomach.

MATERIALS AND METHODS

Transhepatic perforation of the left lobe of the liver into the lesser curvature of the stomach was performed in 35 patients with a presumed diagnosis of malignant obstructive jaundice. Jaundice was found to be caused by a malignant stricture in 32 patients and a benign stricture in three. Perforation was performed under fluoroscopic, endoscopic, and laparoscopic guidance in 33 patients and without laparoscopy in the other two. The hepaticogastric anastomosis was secured with a gastrostomy tube; patency of the tract was maintained with placement of a metallic stent. Kaplan-Meier analysis was used to evaluate survival, anastomosis patency rate, and jaundice recurrence.

RESULTS

Technical success was achieved in all patients. Two (6%) patients had anastomotic obstruction. The actuarial survival rate was 91%, 80%, 59%, and 26% at 1, 3, 6, and 12 months. The mean patency was 234 days +/- 252. The jaundice-free rate among surviving patients was 100%, 96%, 93%, and 80% at 1, 3, 6, and 12 months. The reintervention rate was 14%. Late cholangitis occurred in seven (20%) patients.

CONCLUSION

This peripheral diversion procedure appears to be safe and shows good long-term patency.

Primary liver transplantation without transfusion of red blood cells

BACKGROUND

This study examines factors associated with the performance of orthotopic liver transplantation (OLT) without red blood cell (RBC) transfusion.

METHODS

Between January 1992 and December 1994, 306 primary OLTs were performed with recipients divided into two groups: group 1 patients (61 recipients, 20% of total) underwent transplantation without packed RBCs, and group 2 patients (245 recipients, 80% of cases) received a transfusion of at least 1 unit of RBCs during operation.

RESULTS

Recipients in group 1 compared with group 2 had less advanced liver disease (20% hospitalized and 48% Child's class C versus 58% hospitalized and 73% Child's class C, p < 0.01) and lower frequency of right upper quadrant surgery (13% versus 25%, p < 0.05). Group 1 recipients also had significantly higher preoperative hematocrits (38% versus 33%, p < 0.01), lower prothrombin times (15.4 versus 16.7 seconds, p < 0.001) and partial thromboplastin times (36.9 versus 42.2 seconds, p < 0.01), a greater proportion of patients transplanted by piggyback technique (87% versus 59%, p < 0.001), and shorter operative times (7.9 hours versus 9.2 hours, p < 0.001). Moreover, a greater percentage of patients underwent OLT without RBC transfusion in each successive year: 9% in 1992, 21% in 1993, and 31% in 1994 (p < 0.001). Logistic regression analysis showed the following factors to be independent predictors of OLT without RBC transfusion. Preoperative Hct, United Network of Organ Sharing status, piggyback technique, operative time, and year of transplantation.

CONCLUSIONS

OLT can be performed without transfusion of RBCs in recipients with less advanced liver disease, and surgical technique, along with increased experience by the transplant team, are important factors.

Cyclosporine and the reversibility of chronic vascular rejection

A model of chronic vascular rejection of cardiac allografts has been developed in inbred rats using the WF.1L/Gut congenic strain as donor into LEW recipients. The hearts beat for more than 200 days without the need for exogenous immunosuppression. The histopathology is characterized by cellular rejection, vasculitis, and myointimal arterial wall thickening, and by day 60 posttransplant, there are widespread occlusive vascular changes similar to those seen in human cardiac allografts. CsA, at a dose of 15 mg/kg/d, is effective in preventing as well as reversing the vasculopathy. These data (1) confirm other studies of ours on the reliability of the experimental model using this strain combination, (2) establish the time window of days 40 to 60 whereby mechanisms of lesion regression can be studied, (3) prove the MHC class I and class II antigen incompatibility are not a necessary condition for the generation of the vascular lesions, (4) show that CsA is a useful probe for study of the vasculopathy, and (5) suggest that the model is a useful probe of the mechanism of action of CsA.

Simultaneous liver and whole pancreas harvesting in the multiorgan cadaveric donor

Simultaneous harvesting of the liver and whole pancreas is usually not performed because it is believed that the shared vascular supply of both organs is incompatible with safe grafting. A careful review of the vascular anatomy, however, shows that simultaneous removal of the two organs is feasible, and a technique is described by which the liver is revascularized in the recipient through the celiac axis or the common hepatic artery and the pancreas is revascularized through the superior mesenteric and splenic arteries. When the vascular supply is abnormal, reconstruction of the vascular tree of one or both organs may be needed. The results of this technique used on 10 recipients are analysed.