Roy Calne

Sirolimus (rapamycin)-based therapy in human renal transplantation: similar efficacy and different toxicity compared with cyclosporine.

BACKGROUND Sirolimus (rapamycin) is a potent immunosuppressant with a mechanism of action different from cyclosporine (CsA) or tacrolimus. METHODS In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n=42) or sirolimus (n=41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. RESULTS At 12 months, graft survival (98% sirolimus vs. 90% CsA), patient survival (100% vs. 98%), and incidence of biopsy-confirmed acute rejection (41% vs. 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P< or =0.05) so at 3 and 4 months, and serum uric acid and magnesium were normal. Laboratory abnormalities reported significantly more often with sirolimus included hypertriglyceridemia (51% vs. 12%), hypercholesterolemia (44% vs. 14%), thrombocytopenia (37% vs. 0%), leukopenia (39% vs. 14%), and, of lesser importance, increased liver enzymes and hypokalemia. These abnormalities improved 2 months after transplantation when the sirolimus target trough level was lowered from 30 to 15 ng/ml. Occurrence of cytomegalovirus was comparable (14% vs. 12%); incidences of herpes simplex (24% vs. 10%, P=0.08) and pneumonia (17% vs. 2%, P=0.03) were higher with sirolimus. No gingival hyperplasia was seen with sirolimus, tremor was rare, and hypertension was less frequent (17% vs. 33%). Two malignancies were observed with CsA and none with sirolimus. CONCLUSIONS Results at 12 months suggest that sirolimus can be used as base therapy in the prophylaxis of acute renal transplant rejection, and has a safety profile that differs from CsA.

Orthotopic liver transplantation in the rat. Technique using cuff for portal vein anastomosis and biliary drainage.

In orthotopic liver transplantation in the rat, cuff techniques have been developed for anastomoses of the portal vein and bile duct. These techniques have shortened the clamping time of the portal vein and have resulted in fewer biliary complications improving survival of the liver graft. Eighty-three per cent of the grafted animals have survived for 1 week and several animals have survived for more than 6 months. We believe that use of the cuff method technically simplifies microvascular anastomoses. It may be particularly useful for anastomosis of the portal vein after machine preservation of the donor rat liver.

Cyclosporine: Five Years' Experience in Cadaveric Renal Transplantation

Using a retrospective analysis we compared 79 recipients of cadaveric renal allografts who were treated with cyclosporine as the sole initial immunosuppressant and 29 concurrent transplant recipients treated with conventional immunosuppressants. The cyclosporine-treated group had a slightly higher actuarial patient survival at four years (86 per cent v. 76 per cent). Actuarial graft survival at four years was 70 per cent in the cyclosporine group, as compared with 62 per cent in the conventionally immunosuppressed group. The incidence of acute rejection episodes was 62.1 per cent in the former and 65.5 per cent in the latter. Nephrotoxicity was managed either by reduction of the dose of cyclosporine or by conversion to conventional immunosuppression. Monitoring of trough serum levels of cyclosporine facilitated its administration. Serum creatinine levels have been higher in cyclosporine-treated patients with functioning grafts, but graft deterioration has not occurred after more than three years. Cyclosporine provides adequate immunosuppression for patients with renal allografts. At four years, the rates of patient and graft survival remain superior to those with conventional immunosuppression. In 41 per cent of patients the use of steroids was completely avoided. The longer-term results of this powerful immunosuppressive agent are not yet known.

Normalised intrinsic mortality risk in liver transplantation: European Liver Transplant Registry study

BACKGROUND No model exists for liver transplantation to estimate the mortality risk in a given patient, and no standard by which to assess performance in different centres. We investigated the intrinsic mortality risk in the absence of known mortality risk factors. METHODS We identified mortality risk factors and risk ratios quantified in data from the European Liver Transplant Registry (22,089 patients at 102 centres in 18 countries) registered from 1988 to 1997. To develop a model of the intrinsic risk and the risk ratios for specific factors, univariate and multivariate analyses were done separately for the overall population, for adults, and for children younger than 15 years, and the number of deaths were estimated. We validated the model by comparing mortality in patients without risk factors with the model-adjusted mortality in patients with risk factors. FINDINGS Overall 5-year and 8-year actuarial survival was 66% (95% CI 65-66) and 61% (60-62). 65% of deaths occurred within 6 months. Retransplantation, transplantation for cancer, acute liver failure, fewer than 20 split-liver grafts per year, and a centre workload of fewer than 25 transplants per year were the main risk factors of 12 identified factors. 1-year and 5-year death rates among adults with no risk factors were similar to model estimates (15 [13-16] vs 14% [13-15], and 22 (20-24) vs 23% [21-24]). Corresponding data for paediatric transplants were 9% (7-12) compared with 11% (9-12) and 13% (10-17) compared with 14% (11-16). The reduction of mortality risk in high-volume centres was even greater in patients without risk factors (48 vs 23%, p<0.001). INTERPRETATION The normalised intrinsic mortality risk can be combined with the relative risk ratios of known risk factors to better estimate the mortality risk of a given procedure in a given patient. Centres can assess performance by removing potential bias of donor and recipient selection.

Recurrence of Primary Biliary Cirrhosis after Liver Transplantation

Three patients who had undergone orthrotopic liver transplantation for primary biliary cirrhosis and were being maintained on immunosuppressive therapy were investigated 31/2 to 41/2 years later because of the redevelopment of pruritus and mild jaundice. In one patient pigmentation was again evident, and all three had a rise in the titer of serum mitochondrial antibody after an initial fall. Liver histology showed features of primary biliary cirrhosis with non-suppurative destructive cholangitis, lymphoid aggregates, and increased deposition of copper-binding protein in the absence of cholestasis. None of these features was found in patients who had received grafts for other conditions and had lived for comparable periods, nor were they found in patients who had had rejection with bile-duct abnormalities. The overall findings indicate a recurrence of primary biliary cirrhosis in the donor organ.

Alemtuzumab (CAMPATH 1H) Induction Therapy in Cadaveric Kidney Transplantation—Efficacy and Safety at Five Years

Alemtuzumab is a powerful lymphocyte depleting antibody currently being evaluated in solid organ transplantation. This paper describes 5‐year results of a single center study of alemtuzumab as induction in renal transplantation.

Sirolimus : A potent new immunosuppressant for liver transplantation

BACKGROUND Sirolimus (rapamycin) is a new immunosuppressant that appears to be synergistic with cyclosporine in kidney transplantation, but with a different side-effect profile. This pilot study evaluated sirolimus in liver transplantation. METHODS Patients undergoing orthotopic liver transplantation for primary tumors (8), and later for nonmalignant disease (7), received one of three sirolimus-based immunosuppressive regimens. Protocol A comprised sirolimus, microemulsion cyclosporine (target whole blood concentration: 100 ng/ml), and prednisolone; protocol B omitted prednisolone; and protocol C was sirolimus alone. By 3 months after transplantation, all patients were receiving sirolimus as monotherapy. RESULTS Fifteen patients were treated with a follow-up of 117-806 days. Rejection was more common on monotherapy than double therapy, and absent on triple therapy. The drug was generally well tolerated, with only three patients discontinuing sirolimus: one for hyperlipidemia, one for pneumocystis pneumonia, and one for inability to tolerate the taste of the drug. Two patients discontinued cyclosporine early, both as a result of neurological complications; they continued on sirolimus monotherapy. Five patients died; one suffered a cardiac arrest, and four died from sepsis in association with graft-versus-host disease, recurrent tumor, a paralyzed right hemidiaphragm, and primary nonfunction. CONCLUSIONS Sirolimus combined with cyclosporine provided potent immunosuppression of liver allografts, and sirolimus monotherapy was adequate and well tolerated as maintenance therapy. Side effects of sirolimus over the short period of follow-up were uncommon and reversible with dose reduction or cessation of therapy.

Liver transplantation in patients with alcoholic cirrhosis: selection criteria and rates of survival and relapse.

OBJECTIVE--To evaluate the outcome of liver transplantation in patients with alcoholic cirrhosis with respect to selection criteria, survival, and evidence suggesting a return to harmful drinking. DESIGN--Nine year retrospective study. SETTING--Cambridge and Kings College Hospital liver transplant programme. SUBJECTS--24 Patients (three women, 21 men) with alcoholic cirrhosis. MAIN OUTCOME MEASURES--Survival, rehabilitation, and clinical and laboratory evidence of a return to harmful drinking after transplantation. RESULTS--15 Patients were selected for transplantation because of repeated admission to hospital for the complications of advanced portal hypertension despite abstinence, and six because they had a hepatocellular carcinoma superimposed on alcoholic cirrhosis. Three patients who were not abstinent received transplants. The one year survival rate was 66%, and of the 18 patients surviving at least three months, 17 had been rehabilitated. In three patients laboratory variables and histological examination of the liver suggested a return to drinking, though they did not admit to taking alcohol. These patients represented the only cases in the series that were not abstinent before transplantation. CONCLUSIONS--The survival and rehabilitation of patients who received transplants for alcoholic cirrhosis compared favourably with those of patients who received transplants for cirrhosis of other aetiology. The criteria for selection for liver transplantation in patients with alcoholic cirrhosis should include recurrent complications related to severe portal hypertension despite maximum medical treatment in addition to a minimum period of six months of abstinence before transplantation.

Recurrence of autoimmune chronic active hepatitis following orthotopic liver grafting.

In a 26-year-old woman who had received an orthotopic liver graft for end-stage autoimmune chronic active hepatitis, signs indicative of the original disease became apparent 18 months after transplantation, at a time when the maintenance dose of prednisolone had been reduced to 3 mg daily. In addition to anorexia, nausea, and weight loss there was a reappearance of spider naevi, serum autoantibodies, and elevated levels of immunoglobulin G. Features typical of chronic active hepatitis were observed on examination of the liver biopsy, and both the clinical and histological pictures were unlike those of other possible causes of liver dysfunction, such as chronic rejection, cyclosporine hepa-totoxicity, and non-A non-B chronic hepatitis. Following substitution of azathioprine for cyclosporine and an increased dose of prednisolone (20 mg daily), there was a rapid improvement in the clinical state and both serum transaminases and immunoglobulins returned to normal values. Histological appearances in a repeat biopsy taken six months later were consistent with chronic active hepatitis in remission. This case provides further evidence of the importance of host factors in the pathogenesis of chronic active hapatitis and emphasizes the necessity for selecting appropriate immunosuppressive therapy in such patients after transplantation.

The essential roles of parenchymal tissues and passenger leukocytes in the tolerance induced by liver grafting in rats

Liver allografts in pigs and rodents are uniquely capable of inducing tolerance to themselves and to other grafts of donor tissues, instead of succumbing to the acute rejection that follows transplantation of other allogeneic tissues. We demonstrate here, using normal and chimaeric rat liver grafts, that both the allogeneic liver parenchyma and the intrahepatic leukocytes of donor type contribute to the establishment of long-term tolerance, each component being essential and complementary. The essential role of hepatic parenchyma may be related to its continuous release of soluble transplantation antigens that facilitate tolerogenesis. We suggest that clinical attempts at tolerance induction by the infusion of donor bone marrow-derived leukocytes may likewise be facilitated by the coadministration of soluble transplantation antigens of donor type.