Serum lipid changes in liver transplant recipients in a prospective trial of cyclosporine versus FK506

Calcineurin Antagonizes AMPK to Regulate Lipolysis in Caenorhabditis elegans

Calcineurin is a calcium- and calmodulin-dependent serine/threonine protein phosphatase, and the target of immunosuppressive agent tacrolimus (TAC). The dysfunction of calcineurin, or clinical applications of tacrolimus, have been reported to be associated with dyslipidemia. The underlying mechanisms of calcineurin and tacrolimus in lipid metabolism are largely unknown. Here, we showed that mutations of tax-6 and cnb-1, which respectively encode the catalytic subunit and the regulatory subunit of calcineurin, together with tacrolimus treatment, consistently led to decreased fat accumulation and delayed growth in the nematode Caenorhabditis elegans. In contrast, disruption of the AMP-activated protein kinase (AMPK) encoded by aak-1 and aak-2 reversed the above effects in worms. Moreover, calcineurin deficiency and tacrolimus treatment consistently activated the transcriptional expression of the lipolytic gene atgl-1, encoding triglyceride lipase. Furthermore, RNAi knockdown of atgl-1 recovered the decreased fat accumulation in both calcineurin deficient and tacrolimus treated worms. Collectively, our results reveal that immunosuppressive agent tacrolimus and their target calcineurin may antagonize AMPK to regulate ATGL and lipolysis, thereby providing potential therapy for the application of immunosuppressive agents.

Different Effects of Tacrolimus on Innate and Adaptive Immune Cells in the Allograft Transplantation

While tacrolimus (FK506) is currently used as immunosuppression therapy in transplant recipient, the immunological mechanism remains unknown. Herein, the immunoregulatory effects of FK506 were investigated in the physiological status and allogeneic skin transplantation. FK506 cannot significantly alter the functions of innate immune cells (macrophages and neutrophils) and adaptive immune cells (T cells) in the physiological status. However, it can effectively delay allogeneic skin-graft rejection through ameliorating the T cell responses, but not myeloid-derived innate immune cell responses. Importantly, it did not affect the allograft recipient macrophage innate immune defence capacity to bacteria. In clinics, FK506 treatment can significantly control the cytokine production in T cells, but not non-T cells. This study shows targeting calcineurin signalling, FK506, to be essential in inducing allograft tolerance, but not to damage the innate defence capacity, validating the immune cell phenotypes as a potential marker in transplantation following FK506 treatment.

Higher tacrolimus blood concentration is related to hyperlipidemia in living donor liver transplantation recipients

BACKGROUND

The arrival of tacrolimus has drastically improved AALDLT recipients' survival. However, little data of tacrolimus have been reported concerning its effects on lipid metabolism for AALDLT recipients.

AIM

Out aim was to investigate the relationship between tacrolimus blood concentration and lipid metabolism in AALDLT recipients.

METHODS

The pre and postoperative data of 77 adult patients receiving AALDLT between 2002 and December 2007 were retrospectively reviewed. The postoperative immune suppressive regimen was prednisone with tacrolimus ± mycophenolate mofetil. Prednisone was withdrawn within the first postoperative month. Blood lipids and tacrolimus concentration were detected at the first, third, and sixth month during follow-up. Episodes of acute rejection were diagnosed based on biopsy.

RESULTS

Overall prevalence of post-transplantation hyperlipidemia was 29.9% (23/77) at the sixth postoperative month. The patients were divided into two groups, the hyperlipidemia group and the ortholipidemia group. In the 23 patients with hyperlipidemia, 15 (65%) were hypercholesterolemia, five (22%) were hypertriglyceridemia, and three (13%) patients had both hypercholesterolemia and hypertriglyceridemia. In univariate analysis, only tacrolimus blood concentration at the third and sixth post-transplantation months showed significant difference (8.7 ± 2.1 vs. 6.9 ± 3.2, p = 0.013; 9.2 ± 2.7 vs. 7.3 ± 3.8, p = 0.038, respectively). In multivariate logistic analysis, only two factors appear to be risk factors, namely, tacrolimus blood concentration at the third and sixth post-transplantation months (8.7 ± 2.1 vs. 6.9 ± 3.2, p = 0.043; 9.2 ± 2.7 vs. 7.3 ± 3.8 p = 0.035, respectively).

CONCLUSIONS

Higher tacrolimus blood concentration was related to hyperlipidemia at an early postoperative period. This indicates that tacrolimus blood concentration should be controlled as low as possible in the premise that there is no risk of rejection to minimize post-transplant hyperlipidemia after AALDLT.

Impact of lung transplantation on serum lipids in COPD

BACKGROUND

Severe chronic obstructive pulmonary disease is associated with high HDL cholesterol (HDL-C). We sought to examine the effect of lung transplantation on lipid profiles in patients with COPD.

METHODS

We analyzed 101 lung transplant recipients in a retrospective cohort of patients from two centers in whom lipid values were available both before as well as after transplantation. Sixty-one subjects were transplanted for severe COPD (93% GOLD stage 4).

RESULTS

Eighty-nine percent of subjects with COPD exhibited a decline in HDL-C. Median decline for the COPD cohort was 25 mg/dL (IQR 12-38 mg/dL, p < 0.0001). Non-COPD subjects exhibited no significant changes in HDL-C. Other lipid changes in the COPD cohort included a rise in triglycerides of 70 mg/dL (IQR 35 to 140, p < 0.0001). Decreases in HDL-C levels were independent from the rise in triglyceride levels. Neither LDL-C nor non-HDL-C demonstrated significant changes. Subjects with greater increases in prednisone exposure post-transplant exhibited lesser declines in HDL-C. Compared with tacrolimus, cyclosporine had no effect on observed changes in HDL-C or triglycerides, but was associated with a greater median rise in LDL-C.

CONCLUSIONS

In patients with COPD, lung transplantation results in reductions in the serum levels of HDL-C. These changes are not observed in patients undergoing lung transplantation for diagnoses other than COPD.

Immunosuppressive agents: effects on glucose and lipid metabolism

Immunosuppressive therapies are critical elements in successful organ transplantation. Although immunosuppressant drugs are essential in preventing graft rejection and graft maintenance after transplantation, their use is complicated by adverse effects, many being detrimental to graft and even patient long-term survival. Commonly used agents are associated with dysregulated glucose metabolism and dyslipidemia. This article focuses on the effects of immunosuppressive agents on glucose and lipid metabolism. Adrenal effects of these drugs, where known, also are discussed.

Hyperlipidemia in Iranian liver transplant recipients: prevalence and risk factors

BACKGROUND

Hyperlipidemia is a metabolic complication after liver transplantation (LT). The aim of this study was to investigate the prevalence and risk factors for developing hyperlipidemia in patients who underwent LT in the Shiraz Organ Transplantation Center.

METHODS

Our patients were 170 liver recipients who underwent LT from 1994 to 2006 in the Organ Transplantation Center of the Shiraz University of Medical Sciences. To perform this study we administered questionnaires, including information about age, sex, body mass index (BMI), underlying liver disease, graft type, immunosuppressive medications, and serum levels of triglycerides and cholesterol, before and 6 months after LT. Serum triglyceride and cholesterol levels were considered elevated if they were >150 mg/dl and >250 mg/dl, respectively. Data were analyzed with SPSS software.

RESULTS

There were 108 male and 62 female patients, with a mean age of 31.4 +/- 13.3 years, and the mean duration of follow-up was 25.9 +/- 23.5 months. The average pretransplant serum triglyceride and cholesterol (mean of individual means) levels were 104.6 +/- 73.2 and 109.5 +/- 51.5 mg/dl, respectively, and the average posttransplant levels were 230.1 +/- 131 and 185 +/- 77 mg/dl, respectively. Six months after LT, 119 (70%) and 26 (15.3%) patients developed hypertriglyceridemia and hypercholesterolemia, respectively. Age, sex, BMI, and underlying liver disease were not predictors of hypertriglyceridemia or hypercholesterolemia (P > 0.05). Posttransplant hypertriglyceridemia was significantly more common in patients receiving tacrolimus than in those receiving cyclosporine (P = 0.040), but posttransplant hypercholesterolemia had no significant correlation with type of immune suppression (P > 0.05).

CONCLUSIONS

Hyperlipidemia was common after LT, and hypertriglyceridemia was more common than hypercholesterolemia. Among all risk factors, tacrolimus therapy was correlated with development of hypertriglyceridemia after LT.

Tacrolimus as intervention in the treatment of hyperlipidemia after liver transplant

BACKGROUND

To measure the effect on serum lipids and other risk factors for cardiovascular disease, we converted the primary immunosuppression of dyslipidemic stable liver transplant recipients from cyclosporine A to tacrolimus.

METHODS

Patients underwent a four-month dietary stabilization period (American Heart Association Step II diet) and serum lipid samples were collected for analysis at a central laboratory. After conversion, dietary counseling and lipid analyses were performed over a six-month postconversion observation period.

RESULTS

Enrollment was terminated prematurely due to low patient recruitment rates. Thirteen patients were enrolled and provided postconversion data showing surprisingly strong results. At six months postconversion, total cholesterol (C) was reduced by a mean of 0.61 mmol/L (P=0.017), high density lipoprotein cholesterol (HDL-C) remained unchanged; the mean total C:HDL-C ratio was reduced by 0.87 (P=0.001). Low density lipoprotein cholesterol (LDL-C) reductions were not statistically significant, but we observed a significant and persistent decrease in apolipoprotein B (-0.15 g/L six months postconversion, P=0.031). No changes in homocysteine or in vitamins B6 and B12 were discerned, but although red cell folate remained stable, serum folate increased after conversion. We observed no rejection episodes or any other clinically notable events following conversion.

CONCLUSIONS

In this study, conversion from cyclosporine to tacrolimus provided a safe and well-tolerated alternative that reduced hyperlipidemia and other recognized cardiovascular risk factors.

CARDIOVASCULAR RISK PROFILE AFTER CONVERSION FROM CYCLOSPORINE A TO TACROLIMUS IN STABLE RENAL TRANSPLANT RECIPIENTS

BACKGROUND

Cardiovascular disease is a major cause of morbidity and mortality in renal recipients. In addition to steroids, cyclosporine A (CsA) has been implicated in contributing to increased cardiovascular risk. Conversion from CsA to tacrolimus (TAC) has been shown to improve hyperlipidemia and hypertension, but little is known about the differential effects of CsA versus TAC on other cardiovascular risk factors. We investigated overall cardiovascular risk profile after conversion from CsA to TAC.

METHODS

This was an open-label, single-arm prospective study; 22 adult renal recipients who were receiving CsA-based immunosuppression with serum total cholesterol greater than 200 mg/dL more than 1 year after transplantation were enrolled. CsA was replaced by TAC. Blood pressure, fasting lipid profile, homocysteine, fibrinogen, C-reactive protein, hemoglobin A1c, and creatinine were measured at baseline and at 3 and 6 months after conversion.

RESULTS

There was a significant improvement in fibrinogen (366 +/- 81 - 316 +/- 65 mg/dL, P <0.001), total cholesterol (250 +/- 50 - 207 +/- 29 mg/dL, P <0.001), and low-density lipoprotein cholesterol (155 +/- 43 - 121 +/- 24 mg/dL, P <0.001) after conversion. No new onset or worsening of diabetes mellitus was observed after conversion. There were no significant differences in HDL cholesterol, triglycerides, homocysteine, C-reactive protein, hemoglobin A1c levels, serum creatinine, mean blood pressure, and mean number of antihypertensive medications required before and after conversion.

CONCLUSIONS

Our results indicate that conversion to low-dose TAC may be preferable over CsA for chronic maintenance immunosuppression because it improves the overall cardiovascular risk profile without any apparent adverse effects.

Is there disparity between risk and incidence of cardiovascular disease after liver transplant?

BACKGROUND

Hypertension and hypercholesterolemia are recognized complications of liver transplantation, but whether they contribute to the development of cardiovascular disease is uncertain. We aimed first to determine the prevalence of risk factors for coronary heart disease (CHD) after liver transplantation and second to study the effect of liver transplantation on the predicted 10-year risk of developing CHD and the incidence of cardiovascular events in comparison with a matched local population.

METHODS

Data on blood pressure, serum lipids, weight, diabetes mellitus, smoking, and incidence of myocardial infarction (MI) and stroke were obtained retrospectively from the case notes of 181 consecutive adult liver transplant recipients (median follow-up 54 months). The Framingham coronary risk equations were used to calculate the 10-year probability of developing CHD.

RESULTS

The prevalences of hypertension and hypercholesterolemia after transplantation were 77% and 62%, respectively. The predicted 10-year risk of CHD increased from 6.9% before transplantation to 11.5% at 1 year after transplantation, whereas that of a matched local population was 7%. Compared with a matched nontransplant population, the incidence ratios for MI and stroke were 0.55 (95% confidence interval, 0.01-3.06 ) and 1.45 (95% confidence interval, 0.18-5.22), respectively. No patients died from MI or stroke.

CONCLUSIONS

Liver transplant recipients have a high prevalence of risk factors for cardiovascular disease, exceeding that of the general population, and have a higher predicted risk of developing CHD. Despite this, there were no deaths from CHD or stroke during the study period.

Homozygous familial hypercholesterolemia: specific indication for domino liver transplantation

BACKGROUND

Domino liver transplantation is one possibility to overcome the discrepancy between the small number of liver donors and the long waiting lists. Homozygous familial hypercholesterolemia (FHC) is a genetic disorder of lipoprotein metabolism defined by the absence or small number of functional low-density lipoprotein receptors (LDL-Rs) and the ensuing high levels of serum cholesterol. We report a case of a patient with FHC whose liver was used for domino transplantation in a patient with cirrhosis and hepatocellular carcinoma.

METHODS

The patient diagnosed with FHC received the large part of a split liver. The liver of the patient with FHC was then transplanted into the patient with cirrhosis and hepatocellular carcinoma. Quantification of extrahepatic LDL-R was performed by flow cytometry on monocytes, and the gene expression of LDL-R was assayed by reverse transcriptase-polymerase chain reaction on monocyte-derived macrophages and cultured fibroblasts isolated from the patients.

RESULTS

One year after surgery, the donor's serum cholesterol (without treatment) was normal, and the recipient's serum cholesterol (with simvastatin treatment) was slightly increased. Quantification of peripheral LDL-R on monocytes isolated from the patients revealed values of 6.7% in the patient with FHC and 71% in the patient with cirrhosis and hepatocellular carcinoma. The reverse transcriptase-polymerase chain reaction assay revealed the presence of gene expression for LDL-R.

CONCLUSIONS

Domino transplantation can be efficiently used in a patient with marginal indications for transplantation using a liver from a patient with FHC. The slightly elevated serum cholesterol level in the recipient may be explained by the normal function of extrahepatic LDL-R.

Steroid withdrawal after pediatric liver transplantation: a long-term follow-up study in 109 recipients

BACKGROUND

Steroids remain an important component of maintenance immunosuppression in liver transplantation, but when administered for a long period they may be associated with multiple severe side effects, particularly growth suppression in children. This study was conducted to clarify the balance of potential benefits and risks of steroid withdrawal (SW) in pediatric liver transplantation.

METHODS

Between April 1984 and July 2000, 109 pediatric recipients with SW and at least 12 months of follow-up after SW were retrospectively reviewed and divided into three groups according to the type of anticalcineurin at SW: group I (cyclosporine, n=25), group II (cyclosporine microemulsion, n=25), and group III (tacrolimus, n=59). Steroids were withdrawn after a three-step reduction of steroid dosage (taper down to the substitution dose of 0.25 mg/kg/day, switch to alternate-day therapy, progressive SW). Patients were regularly followed up for clinical and biochemical monitoring.

RESULTS

Median follow-up was 8.1 (range, 1.6-16.8) years. After SW, neither chronic rejection nor graft nor patient loss occurred. A trend toward lower anticalcineurin trough levels was observed in all groups. Glomerular filtration rate and fasting cholesterol were significantly better in group III (P<0.05). Median height z-score in all patients was -1.1 SD on alternate-day steroids versus -0.2 SD at the time of SW. Height z-score was slightly better in group III (NS). Early SW within 2 years after transplantation allowed a slightly better gain in growth.

CONCLUSIONS

SW in pediatric liver transplantation is safe and may be beneficial to height outcome. Tacrolimus seems to offer several advantages in the long-term outcome.

Influence of hypercholesterolemia on patient and graft survival in recipients of kidney transplants

AIM

The aim of this retrospective, single centre study, was to study the effect of pre- and post-transplant serum total cholesterol (TC) on patient and graft survival. We also sought to see whether patients who had very high TC (>8 mmol/L) had a higher incidence of graft failure and patient mortality compared with those whose cholesterol was only moderately elevated.

METHODS

Records of 935 cadaver kidney transplants between 1984 and 1998 were examined. Patients were placed into three groups based on TC level: <5.5 mmol/L (group 1), 5.5-8 mmol/L (group 2) and >8 mmol/L (group 3). The mean TC value from the first five post-transplant years was taken to seek a correlation between TC and post-transplant events.

RESULTS

The mean graft follow-up was 66.9 +/- 50.1 months, ranging from 0.1 to 191 months, while mean patient follow-up was 83.8 +/- 50.1 months, ranging from 0.5 to 191.6 months. Pre-transplant TC was available in 201 patients (21.5%), and post-transplant data was available (for first 5 yr) in 655 patients (70%). During the study period, 220 patients (23.5%) had died, 285 (30.5%) of the grafts had failed during the follow-up, while 129 (13.8%) of the patients died with a functioning graft. We found significantly longer survival of patients having a pre-transplant TC below 5.5 mmol/L vs. patients whose pre-transplant TC was above 5.6 mmol/L (p = 0.02). We also compared patients who had very high pre-transplant TC (>8 mmol/L) level with those whose TC was moderately elevated (5.5-8 mmol/L) and found that there was no higher incidence of graft failure (p = 0.77) nor patient mortality (p = 0.83). No difference could be found in graft survival based on pre-transplant TC. We also did not find a detrimental influence of post-transplant TC on the patient or graft survival. Diabetes mellitus (p = 0.006) and age over 50 yr (p = 0.007) affected patient survival, while low cyclosporine levels (p = 0.02) and acute rejection episodes (p = 0.009) affected graft survival. The mode of dialysis and time on dialysis prior to transplantation did not affect patient and graft survival.

CONCLUSIONS

We found significantly greater survival of patients having a pre-transplant TC below 5.5 mmol/L. No difference could be found in graft survival based on pre-transplant TC. Post-transplant TC did not adversely affect patient or graft survival.

[Nutritional therapy in liver transplantation]

BACKGROUND

Malnutrition, sometimes severe is common in patients with chronic hepatic diseases who are candidates for liver transplantation. Nutritional therapy can induce partial or total correction of such deficiencies, improving clinical conditions and prognosis of patients who face the great defiance of liver transplantation.

AIMS

Brief revision of hepatic role in the metabolism of several nutrients. Description of available methods of dietary therapy and its application both under different abnormal hepatic conditions and pre and post-transplant periods. The role of nutritional intervention in metabolic side effects due to immunosuppressive drugs.

CONCLUSION

Nutritional therapy is a valuable adjuvant resource to the clinical treatment of candidates and submitted patients to hepatic transplantation providing better prognosis and improved life quality.

Calcineurin inhibitors and post-transplant hyperlipidaemias

Cardiovascular disease is now the leading cause of death in transplant recipients. This is due, in part, to the vulnerability of these patients to a complicated set of conditions including hypertension, diabetes mellitus, and post-transplant hyperlipidaemia (PTHL). PTHL is characterised by persistent elevations in total serum cholesterol, low density lipoprotein cholesterol and triglyceride levels. The causes of PTHL are complex and not fully understood, however several classes of immunosuppressants including the corticosteroids, rapamycins and calcineurin inhibitors, appear to play a role. PTHL has been observed in most studies in which patients received calcineurin inhibitor-based regimens, and has been observed with both tacrolimus and cyclosporin. Comparing these calcineurin inhibitors with regard to the relative incidence or severity of PTHL occurring during treatment is difficult because of the use of higher doses of corticosteroids in cyclosporin-based regimens, as compared with tacrolimus-based regimens. However, current expert opinion suggests that the discrepancies in the relative incidence and severity of PTHL are largely accounted for by this difference in corticosteroid dose. At this point in time, evidence for potential differences is scant and inconclusive. Further study is needed, not only to investigate differences in lipid profile, but also of the relative effects of these immunosuppressants on long term graft function as well as on cardiovascular morbidity and mortality. PTHL can be successfully managed with a combination of dietary management, reduction and, if appropriate, withdrawal of corticosteroids, and the administration of lipid-lowering drugs. With this combination of therapeutic options, the threats to long term health posed by PTHL may be effectively addressed.

Can the potential benefits of statins in general medical practice be extrapolated to liver transplantation?

Hypercholesterolemia is a common complication of liver transplantation and is a risk factor for cardiovascular disease after renal and heart transplant. The effect of hyperlipidemia after liver transplantation is less certain, but a less favorable outcome is to be expected. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors or statins have proven efficacy in reducing serum cholesterol and mortality from cardiovascular disease in the general population. Early evidence shows that statins are safe and effective in treating hypercholesterolemia after liver transplantation. Studies in cardiovascular disease have shown that statins exhibit beneficial properties independent of lipid-lowering. These include anti-inflammatory effects and improvement in endothelial function. Recently, statins were shown to repress induction of major histocompatibility complex class II complexes by interferon-gamma, which in turn suppresses activation of T lymphocytes. Such effects may assume significance when using statins after solid-organ transplants. Pravastatin has been shown to reduce acute rejection after cardiac and renal transplantation and to also reduce natural killer cell cytotoxicity in these populations. It remains to be seen whether statins will demonstrate similar benefits after liver transplantation.

Risk factors for and management of post-transplantation cardiovascular disease

The mortality rates due to cardiovascular disease (CVD) in transplant recipients are greater than in the general population. CVD is a major cause of both graft loss and patient death in renal transplant recipients, and improving cardiovascular health in transplant recipients will presumably help to extend both patient and graft survival. Further studies are needed to better evaluate the effectiveness of risk modification on subsequent CVD morbidity and mortality. There is no reason to consider risk factors for CVD such as hyperlipidaemia, hypertension and diabetes mellitus in transplant recipients differently from in the general population. In addition, there are specific transplantation risk factors such as acute rejection episodes and the use of immunosuppressive drugs. It is obvious that several of the immunosuppressive agents used today have disadvantageous influences on risk factors for CVD such as hyperlipidaemia, hypertension and post-transplantation diabetes mellitus (PTDM), but the relative importance of immunosuppressant-induced increases in these risk factors is basically unknown. This may be a strong argument for the selective use and individual tailoring of immunosuppressive agents based upon the risk factor profile of the patient, without jeopardising the function of the graft. Hyperlipidaemia is common after transplantation, and immunosuppression with corticosteroids, cyclosporin, or sirolimus (rapamycin) causes different types of post-transplantation hyperlipidaemia. However, to date, no studies have demonstrated that lipid lowering strategies significantly reduce CVD morbidity or mortality and improve allograft survival in transplant recipients. Several studies using preventive or interventional approaches are ongoing and will be reported in the near future. Post-transplantation hypertension appears to be a major risk factor determining graft and patient survival, and immunosuppressive agents have different effects on hypertension. Controlled studies support the opinion that post-transplantation hypertension must be treated as strictly as in a population with essential hypertension, diabetes mellitus, or chronic renal failure. As increasing numbers of immunosuppressive agents become available for use, we may be in a better position to tailor immunosuppressive therapy to the individual patient, avoiding the use of diabetogenic drugs, drug combinations, or inappropriate doses in patients susceptible to PTDM. Multiple acute rejection episodes have also been demonstrated to be a risk factor for CVD - a strong argument for the use of immunosuppressive drugs to reduce acute rejection. Until we have a better understanding from ongoing landmark studies on the management of CVD, presently available therapy to reduce risk factors needs to be used together with individual tailoring of immunosuppressive therapy with the aim of reducing CVD in these patients.

Beneficial effects of converting liver transplant recipients from cyclosporine to tacrolimus on blood pressure, serum lipids, and weight

Hypertension and hyperlipidemia are more prevalent after liver transplantation with cyclosporine as the primary immunosuppressive agent compared with tacrolimus. To determine whether blood pressure, serum lipid level, or weight improves when patients switch immunosuppression therapy, we retrospectively studied 26 liver transplant recipients with stable graft function who had been converted from cyclosporine to tacrolimus therapy with a median follow-up of 8 months. One of the 26 patients developed pruritus necessitating withdrawal of tacrolimus. The results therefore concern the remaining 25 patients. With the exception of a small decrease in bilirubin level (P <.05), there was no difference in graft or renal function after conversion. Mean systolic blood pressure decreased from 158 +/- 25 to 148 +/- 22 mm Hg over a mean of 8 +/- 3 months after conversion to tacrolimus (P =.015), whereas mean serum cholesterol level decreased from 5.3 +/- 0.9 to 4.9 +/- 0.9 mmol/L (P =.01). Sixty-eight percent of the patients lost weight, from a mean of 79.4 +/- 22.6 to 76.1 +/- 20.1 kg, in the 11 months after switching to tacrolimus therapy (P =.024). Serum triglyceride and blood glucose levels did not change, and no patient developed diabetes mellitus after conversion. These results indicate that switching from cyclosporine to tacrolimus can reduce blood pressure, serum cholesterol level, and weight after liver transplantation.

Influence of tacrolimus and prednisone on serum lipids after liver transplantation

BACKGROUND

Hyperlipidemia after orthotopic liver transplant is thought to be the result of the immunosuppression therapy given postoperatively. The purpose of this study was to evaluate serum lipid levels pretransplant, 4 months, and 12 months posttransplant.

METHODS

A retrospective chart review of 50 patients after liver transplantation was completed. Pretransplant serum lipid levels (triglyceride, cholesterol, and high-density lipoprotein [HDL]) were compared with values at 4 months and 12 months posttransplantation. Pretransplant serum lipid levels were compared using one factor analysis of variance (ANOVA) model. Values between the viral, alcohol, and cholestatic groups were compared using two-factor ANOVA model.

RESULTS

Of the 50 patients (22 females, 28 males) with a mean age of 52 years (range, 16 to 69 years), all 50 had completed their 12-month follow-up at the time of this study. The etiology of liver disease included: viral hepatitis (21), alcohol (8), primary biliary cirrhosis and sclerosing cholangitis (7), and others (14). The protocol for immunosuppression included tacrolimus and prednisone. Mean serum triglyceride levels included: 134 mg/dL pretransplant, 155 mg/dL at 4 months, and 169 mg/dL at 12 months posttransplant (p = .117). Mean total serum cholesterol levels included: 174 mg/dL pretransplant, 165 mg/dL at 4 months, and 163 mg/dL at 12 months posttransplant (p = .654). Mean HDL levels included: 39 mg/dL pretransplant, 45 mg/dL at 4 months and 44 mg/dL at 12 months posttransplant (p = .032). There was not a significant difference in serum lipids between the different categories of liver diseases.

CONCLUSIONS

Although a significant positive effect was observed with HDL, the present data show that total serum cholesterol and triglyceride did not change significantly over time after orthotopic transplantation. This is most likely related to the type of immunosuppressive therapy given posthepatic transplantation.

Modern immunosuppression

The current treatment of posttransplant lymphoproliferative disease (PTLD) includes prophylaxis at the time of transplant, decreasing or stopping immunosuppresion and initiation of antiviral therapy in patients with polymerase chain reaction or clinical evidence of PTLD, and judicial reintroduction of immunosuppression in patients who have cleared their PTLD and have begun to have rejection. The pharmacology, pharmacokinetics, notable side effects, and toxicities of the immunosuppressive agents are described in this article. At the conclusion of each section the author's current practice with these agents and treatment strategies are described.

Lipolysis and lipid oxidation in cirrhosis and after liver transplantation

On the basis of the finding that plasma glycerol concentration is not controlled by clearance in healthy humans, it has been proposed that elevated plasma free fatty acid (FFA) and glycerol concentrations in cirrhotic subjects are caused by accelerated lipolysis. This proposal has not been validated. We infused 10 volunteers, 10 cirrhotic subjects, and 10 patients after orthotopic liver transplantation (OLT) with [1-(13)C]palmitate and [(2)H(5)]glycerol to compare fluxes (R(a)) and FFA oxidation. Cirrhotic subjects had higher plasma palmitate (52%) and glycerol (33%) concentrations than controls. Palmitate R(a) was faster (1.45+/-0.18 vs. 0.85+/-0.17 micromol x kg(-1) x min(-1)) but glycerol R(a) and clearance slower (1.20+/-0.09 vs. 1.90+/-0.24 micromol x kg(-1) x min(-1) and 21.2+/-1.2 vs. 44.7+/- 4.9 ml x kg(-) x h(-1), respectively) than in controls. After OLT, plasma palmitate and glycerol concentrations and palmitate R(a) did not differ, but glycerol R(a) (1.16+/-0.11 micromol x kg(-1) x min(-1)) and clearance (26.7+/-2.4 ml x kg(-1) x h(-1)) were slower than in controls. We conclude that 1) impaired reesterification, not accelerated lipolysis, elevates FFA in cirrhotic subjects; 2) normalized FFA after OLT masks impaired reesterification; and 3) plasma glycerol concentration poorly reflects lipolytic rate in cirrhosis and after OLT.

Long-term medical complications in patients surviving > or = 5 years after liver transplant

BACKGROUND

Short-term outcomes of liver transplantation are well reported. Little is known, however, about long-term results in liver recipients surviving > or =5 years. We sought to analyze long-term complications in liver recipients surviving > or =5 years after transplant, to assess their medical condition and to compare findings to the general population.

METHODS

We analyzed the chart and database records of all patients (n=139) who underwent liver transplantation at a major transplant center before January 1, 1991. Outcome measures included the presence of diabetes, hypertension, heart, renal or neurological disease, osteoporosis, incidence of de novo malignancy or fracture, or other pathology, body mass index, serum cholesterol and glucose, liver function, blood pressure, frequency of laboratory and clinic follow-up, current pharmacological regimen, and late rejection episodes.

RESULTS

Ninety-six patients (70%) survived > or =5 years. Compared to numbers expected based on U.S. population rates, transplant recipients had significantly higher overall prevalences of hypertension (standardized prevalence ratio [SPR]=3.07, 95% confidence interval [CI], 2.35-3.93) and diabetes (SPR=5.99, 95% CI, 4.15-8.38), and higher incidences of de novo malignancy (standardized incidence ratio [SIR]=3.94, 95% CI, 2.09-6.73), non-Hodgkin's lymphoma (SIR=28.56, 95% CI, 7.68-73.11), non-melanoma skin cancer (estimated SIR> or =3.16) and fractures in women (SIR=2.05, 95% CI, 1.12-3.43). Forty-one of 87 (47.1%) patients were obese, and 23 patients (27.4%) had elevated serum cholesterol levels (> or =240 mg/dl, 6.22 mmol/L), compared to 33% and 19.5% of U.S. adults, respectively. Prevalences of heart or peptic ulcer disease were not significantly higher.

CONCLUSIONS

Liver transplantation is being performed with excellent 5-year survival. Significant comorbidities exist, however, which appear to be related to long-term immunosuppression.

The effects of maintenance doses of FK506 versus cyclosporin A on glucose and lipid metabolism after orthotopic liver transplantation

BACKGROUND

Posttransplant diabetes mellitus (PTDM) has gained widespread attention due to the micro and macro-vascular complications that increase the morbidity and mortality of patients receiving solid organs. The higher incidence of PTDM has been mainly attributed to the immunosuppressive therapy. Therefore, this study compares the metabolic side effects of low dose maintenance therapy of FK-506 and Cyclosporin A (CsA) in 14 patients 1 year after orthotopic liver transplant and analyzes possible factors that contribute to the development of PTDM.

METHODS

Two groups (n=7) differing in their immunosuppressive regimen (FK506 or CsA) were matched to eight control subjects and compared to each other. The effects of in vivo insulin action were assessed by means of the euglycemic hyperinsulinemic clamp technique. Arginine stimulation tests at normo- (5.5 mM) and hyperglycemic (15 mM) levels were performed and the acute insulin, C-peptide, and glucagon response (2-5 min) to arginine were determined.

RESULTS

Insulin sensitivity (total glucose disposal) was statistically lower in patients treated with FK-506 and CsA (5.05+/-0.47 and 5.05+/-0.42 mg/kg/min) as compared to controls (6.62+/-0.38 mg/kg/min) (P<0.02), with a significantly higher nonoxidative glucose disposal for the control group (P<0.01), and lower free fatty acid levels (P<0.05). Absolute values for acute insulin response were higher but not significantly different for the transplanted groups. The lower percentage of increase of insulin release after arginine stimulation observed in the FK-506 and CsA groups as compared with controls (754%+/-100, 644%+/-102 vs. 1191%+/-174) (P<0.03 and 0.02, respectively), suggests a reduced beta cell secretory reserve in both treated groups. Also, the acute glucagon response to arginine during hyperglycemia declined less in the FK-506 (28%) and CsA groups (29%) compared with controls (48%) (P<0.05) indicating a defect in the pancreatic beta cell-alpha cell axis.

CONCLUSIONS

There are no major metabolic differences on low maintenance doses between FK-506 and CsA. Both immunosuppressant agents contribute to the development of PTDM at different levels.

Serum cholesterol changes in long-term survivors of liver transplantation: a comparison between cyclosporine and tacrolimus therapy

The aim of this study was to compare the long-term effect of tacrolimus and cyclosporine therapies on serum cholesterol levels in liver transplant recipients. We retrospectively studied 127 consecutive adult liver transplant recipients who survived for at least 1 year after transplantation. Basal immunosuppression consisted of cyclosporine plus prednisone in 100 patients and tacrolimus plus prednisone in 27 patients. Hypercholesterolemia was defined as a fasting serum cholesterol level greater than 220 mg/dL. Mean follow-up was 39 months. No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar. Significantly more tacrolimus-treated patients were steroid free in the first and second year of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P <.01). In the third year of follow-up, this difference was not significant (77% v 56%). The overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 14 of 70 patients with and without steroids, respectively (P <.002). Also, mean cholesterol levels were 224 +/- 70 and 191 +/- 48 mg/dL before and after steroid withdrawal, respectively, P <.001. Hypercholesterolemia was found in 43.7% of the patients during cyclosporine plus prednisone therapy compared with 46.1% of the patients during tacrolimus plus prednisone therapy (P <.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (P <.01). Hypercholesterolemia was found in 22% of the patients during cyclosporine monotherapy compared with 15% during tacrolimus monotherapy (P <.5). No differences were found in mean cholesterol levels during follow-up when both monotherapy groups were compared. In conclusion, a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, mainly when steroids were still part of the immunosuppressive treatment.

A prospective randomized trial of mycophenolate mofetil with neoral or tacrolimus after orthotopic liver transplantation

BACKGROUND

The success of liver transplantation in this decade has become the stimulus to extend the donor and recipient pool. Reducing early posttransplant morbidity to maintain our success, as we expand our frontiers, has led us to focus on balanced testing of multidrug immunosuppression regimens.

METHODS

A prospective trial in orthotopic liver transplantation using Mycophenolate Mofetil and an identical steroid taper with randomization of patients to Neoral (N) or Tacrolimus (FK) is the basis of this report. This was an intent-to-treat study designed to compare the 6-month primary endpoints of rejection and infection and to compare the 6-month secondary endpoints of liver function, renal function, bone marrow function, hypertension, and serum cholesterol levels.

RESULTS

Ninety-seven patients completed the 6-month follow-up period (N=49, FK=48). The actual 6-month patient and graft survival rates were 98% and 94%, respectively. There was no difference in the number of patients with rejection episodes (N=11, FK=8) (P=0.61). There were 24 infections (3 cytomegalovirus) in the FK group and 30 infections (9 cytomegalovirus) in the N group. The cholesterol levels at 6 months were not significantly different (P=0.07) between the groups. The other secondary 6-month endpoints were not significantly different, except total bilirubin, which was lower in the FK arm (P=0.02).

CONCLUSIONS

The use of Mycophenolate Mofetil with N or FK and an identical steroid taper after orthotopic liver transplantation is associated with excellent graft and patient survival, and at 6 months, only 191% of the patients experienced rejection, with a 48% overall infection rate.

Oxidative stress and lipid abnormalities in renal transplant recipients with or without chronic rejection

BACKGROUND

The histological picture of chronic rejection with endothelial lesions and vascular hyperplasia resembles the early arteriosclerotic lesions. As increasing evidence suggests a role for oxidative stress in arteriosclerosis, we examined whether chronic rejection in renal transplant recipients was associated with increased oxidative stress markers.

METHODS

We investigated lipid metabolism and oxidative stress in 77 renal transplant recipients. Group I patients (n=34; 48+/-2 years old, 12 women, 22 men) had no clinical or histological signs of chronic rejection, whereas group II patients (n=43; 47+/-3 years old, 15 women, 28 men) had histologically proven chronic rejection. All patients were treated with cyclosporine and steroids. Lipid metabolism was evaluated by determining total cholesterol, triglycerides, high-density lipoprotein cholesterol, apolipoproteins AI and B, and lipoprotein (a). Oxidative stress was evaluated by determining: (i) the end product of lipid peroxidation, malonyldialdehyde (MDA), and erythrocyte polyunsaturated fatty acids; (ii) the nonenzymatic antioxidant system: erythrocyte alpha-tocopherol and glutathione; and (iii) the enzymatic antioxidant system: erythrocyte superoxide dismutase and plasma glutathione peroxidase. Results were compared with those of a control group (38 healthy volunteers).

RESULTS

Compared with controls, renal transplant recipients had significantly increased total cholesterol, triglyceride, and apolipoprotein B levels; they also had, in association with these lipid abnormalities, a significant increase in MDA and a significant decrease in erythrocyte polyunsaturated fatty acids, as well as a significant decrease in enzymatic and nonenzymatic antioxidant defense mechanisms. In contrast to lipid disturbances, where no difference was observed between groups I and II, markers of oxidative stress were significantly higher in group II compared with group I (MDA: 1.87+/-0.43 and 1.62+/-0.31 nmol/ml, respectively, P<0.05). The red blood cell antioxidative defense mechanisms were significantly decreased in group II compared with controls (erythrocyte alpha-tocopherol: 0.61+/-0.38 and 1.08+/-0.31 mg/L, respectively, P<0.01; superoxide dismutase: 1.08+/-0.2 and 1.32+/-0.31 U/mg Hb, respectively, P<0.01).

CONCLUSION

Our data show that oxidative stress with a decrease in antioxidant defenses is associated with kidney transplantation. In addition, oxidative stress markers are particularly increased in transplant recipients with chronic rejection, which suggests that oxidative stress may participate in the development and/or progression of vascular lesions observed in these patients.

Effects of tacrolimus on hyperlipidemia after successful renal transplantation: a Southeastern Organ Procurement Foundation multicenter clinical study

BACKGROUND

Tacrolimus has been shown to have a less adverse effect on the lipid profiles of transplant patients when the drug is started as induction therapy. In order to determine the effect tacrolimus has on lipid profiles in stable cyclosporine-treated renal transplant patients with established hyperlipidemia, a randomized prospective study was undertaken by the Southeastern Organ Procurement Foundation.

METHODS

Patients of the 13 transplant centers, with cholesterol of 240 mg/dl or greater, who were at least 1 year posttransplant with stable renal function, were randomly assigned to remain on cyclosporine (control) or converted to tacrolimus. Patients converted to tacrolimus were maintained at a level of 5-15 ng/ml, and control patients remained at their previous levels of cyclosporine. Concurrent immunosuppressants were not changed. Levels of total cholesterol, triglycerides, total high-density lipoprotein, low-density lipoprotein (LDL), very-low-density lipoprotein, and apoproteins A and B were monitored before conversion and at months 1, 3, and 6. Renal function and glucose control were evaluated at the beginning and end of the study (month 6).

RESULTS

A total of 65 patients were enrolled; 12 patients failed to complete the study. None were removed as a result of acute rejection or graft failure. Fifty-three patients were available for analysis (27 in the tacrolimus group and 26 controls). Demographics were not different between groups. In patients converted to tacrolimus treatment, there was a -55 mg/dl (-16%) (P=0.0031) change in cholesterol, a -48 mg/dl (-25%) (P=0.0014) change in LDL cholesterol, and a -36 mg/dl (-23%) (P=0.034) change in apolipoprotein B. There was no change in renal function, glycemic control, or incidence of new onset diabetes mellitus in the tacrolimus group.

CONCLUSION

Conversion from cyclosporine to tacrolimus can be safely done after successful transplantation. Introduction of tacrolimus to a stable renal patient does not effect renal function or glycemic control. Tacrolimus can lower cholesterol, LDL, and apolipoprotein B. Conversion to tacrolimus from cyclosporine should be considered in the treatment of posttransplant hyperlipidemia.

Lipoprotein changes in children after liver transplantation: mild hypertriglyceridemia and a decrease in HDL3/HDL2 ratio

Hyperlipidemia is frequently observed in patients who undergo renal, cardiac, bone marrow, or liver transplantation, and its contribution to the long-term morbidity and survival of patients with organ transplants may be substantial. In the few studies that have focused on the pediatric age group, findings have been inconsistent. The lipoprotein profile of 10 children after liver transplantation was characterized and compared with those in normal population controls and 10 healthy siblings. Plasma triglyceride and cholesterol concentrations were determined, lipoprotein fractions (very-low-density lipoprotein [VLDL], low-density lipoprotein [LDL], and high-density lipoproteins [HDL2 and HDL3]) were isolated, their chemical compositions were analyzed (protein, phospholipids, triglycerides, free cholesterol, and cholesteryl ester), and the percent relative weight composition of the particles was calculated. Plasma triglyceride and VLDL cholesterol levels were higher post-liver transplantation (P < .05): triglycerides (mean +/- SD), 115.1 +/- 58.7 mg% versus 76.6 +/- 20.9 mg% in siblings and 60.0 +/- 25.0 mg% in normal population controls; very-low-density lipoprotein cholesterol (VLDL-C), 23.0 +/- 11.7 mg% versus 15.3 +/- 4.7 mg% and 13.0 +/- 8.0 mg%, respectively. Plasma triglyceride levels did not correlate with the length of the period after liver transplantation. Levels of LDL-C and total HDL-C and the relative weight composition of VLDL, LDL, HDL2, and HDL3 particles did not differ between post-liver transplantation children and controls. Posttransplantation, levels of HDL3, the normally predominant HDL subfraction, were decreased relative to HDL2 levels (HDL3, 1.3; HDL2, 2.3). Because this observed relative increase in larger cholesteryl ester-rich HDL particles (HDL2) may result from inhibition of cholesteryl ester-triglyceride transfer processes, cholesteryl ester transfer protein activity was assayed. Cholesteryl ester transfer protein activity did not differ between patients and controls. Thus, the lipoprotein changes observed in children post-liver transplantation are mild hypertriglyceridemia and a significant increase in HDL2 relative to HDL3. Because HDL2 is regarded as protective against atherosclerosis, this may be of clinical relevance.

Post-transplant hyperlipidaemia

The correction of post-transplant hyperlipidaemia warrants the judicious and timely use of pharmacological agents with dietary modification and exercise. Reduction in hyperlipidaemia may have some role in decreasing the incidence of chronic rejection of allografts. The awareness that the morbidity and mortality of atherosclerotic disease may be lowered by active intervention will result in a better quality of life for transplant recipients.

Clinical chemistry and post-liver-transplant monitoring

Liver transplantation is an accepted therapy for end-stage liver disease. After allografting, a variety of clinical problems may require laboratory involvement for accurate and timely diagnosis and intervention. Critical factors in the choice of a laboratory test menu to support a transplant program include turnaround times that support clinical decisionmaking, real diagnostic value, and real value for money. Particular clinical problems, whose early presentation must be anticipated, include graft ischemia, primary nonfunction, and hepatic artery thrombosis. Acute rejection is common at 5-10 days posttransplantation, the principal target being the biliary tree. Longer-term problems are associated with the therapeutic drug measurement of cyclosporin A and, increasingly, tacrolimus (FK506); the side effects of immunosuppressant therapy also require monitoring. A successful liver transplant program can be adequately supported with a simple battery of automated tests that are cheap, fast, and available at all times.

Post-transplant diabetes mellitus. The role of immunosuppression

Immunosuppressive agents increase the risk of death due to coronary disease or stroke by their ability to cause 3 different adverse effects: dyslipidaemia, hypertension and hyperglycaemia. Post-transplant diabetes mellitus has emerged as a major adverse effect of immunosuppressants. As recipients of organ transplants survive longer, the secondary complications of diabetes mellitus have assumed greater importance. There is a need for a precise definition of post-transplant diabetes mellitus to facilitate inter-centre comparison and to study the natural history of post-transplant diabetes mellitus. We recommend broad criteria to define hyperglycaemia, as a fasting blood glucose level of > 400 mg/dl at any point or > 200 mg/dl for 2 weeks, or a need for insulin treatment for at least 2 weeks. We also recommend serial measurements of HbA1c. Cyclosporin and tacrolimus cause post-transplant diabetes mellitus by a number of mechanisms, including decreased insulin secretion, increased insulin resistance or a direct toxic effect on the beta cell. For corticosteroids, the induction of insulin resistance seems to be the predominant factor. However, few studies have examined the mechanism of diabetogenicity at the molecular level. This may hold the key for pharmacological manipulation of current immunosuppressive regimens which may result in decreased metabolic complications. Corticosteroid sparing regimens have been shown to reduce the metabolic complications of immunosuppressants including post-transplant diabetes mellitus. However, their use should be balanced against the increased incidence of transplant rejections. Post-transplant diabetes mellitus may be organ-specific irrespective of the immunosuppressant used. Tacrolimus causes a high incidence of post-transplant diabetes mellitus in recipients of kidney transplants (upto 20% in some reports); the diabetogenicity of cyclosporin-based regimens is comparable with that of tacrolimus-based regimens in recipients of liver transplants. A few clinical studies in which attempts were made to discontinue cyclosporin resulted in an unacceptable loss of the transplant. In the case of tacrolimus, complete withdrawal of immunosuppression may be possible in selected patients with liver transplants. However, post-transplant recipients who may benefit from this approach are difficult to identify. In some early series, patients received doses of tacrolimus that were approximately 2 to 3 times higher than those currently used, which may have resulted in a higher incidence of post-transplant diabetes mellitus. More recently, it has been shown that tacrolimus was successful in salvaging whole pancreatic grafts which were maintained on cyclosporin. Tacrolimus-based immunosuppression as primary therapy was also used with remarkable success in solitary whole pancreas transplants. Strategies to reduce the metabolic complications of immunosuppressants should be pursued aggressively as this will directly lead to a decrease in long term cardiovascular adverse effects.

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.

Renal dysfunction associated with liver transplantation

It has been known for some time that a variety of liver diseases affect kidney function, but renal dysfunction associated with orthotopic liver transplantation has received scant attention. Although the mechanisms mediating these abnormalities are incompletely defined, advances in the understanding of renal pathophysiology after liver transplantation have made it possible to develop new treatment strategies. Aggressive and early intervention to diagnose and treat renal complications associated with liver transplantation should be the goal for transplant centres.