Late-onset renal failure after liver transplantation: role of posttransplant alcohol use

Impact of Pretransplant Diabetes on Outcomes After Liver Transplantation: An Updated Meta-analysis With Systematic Review

BACKGROUND

Preliver transplant diabetes mellitus (pre-LT DM) is a common comorbidity in LT recipients associated with poorer post-transplant survival. However, its relationship with other important outcomes, including cardiovascular and renal outcomes, remains unclear. This meta-analysis aims to provide an updated analysis of the impact of pre-LT DM on key post-LT outcomes.

METHODS

A search was conducted in Medline and Embase databases for articles comparing the post-transplant outcomes between patients with and without pre-LT DM. Pairwise analysis using random effects with hazard ratios (HRs) was used to assess the longitudinal post-LT impacts of pre-LT DM. In the absence of HR, pooled odds ratios analysis was conducted for secondary outcomes.

RESULTS

Forty-two studies involving 77,615 LT recipients were included in this analysis. The pooled prevalence of pre-LT DM amongst LT recipients was 24.79%. Pre-LT DM was associated with significantly lower overall survival (HR, 0.65; 95% confidence interval, 0.52-0.81; P <0.01) and significantly increased cardiovascular disease-related mortality (HR, 1.78; 95% confidence interval, 1.11-2.85; P =0.03). Meta-regression of other patient characteristics identified Asian ethnicity and hypertension to be significant predictors of worse overall survival, whereas African-American ethnicity was associated with significantly improved overall survival in patients with pre-LT DM. Further analysis of secondary outcomes revealed pre-LT DM to be a significant predictor of post-LT cardiovascular events and end-stage renal disease.

CONCLUSIONS

The present study illustrates the impact of pre-LT DM on post-LT survival, and cardiovascular and renal outcomes and provides a sound basis for revision of preoperative management of pre-LT DM.

Kidney Disease After Nonkidney Solid Organ Transplant

Nonkidney solid organ transplants (NKSOTs) are increasing in the United States with improving long-term allograft and patient survival. CKD is prevalent in patients with NKSOT and is associated with increased morbidity and mortality especially in those who progress to end-stage kidney disease. Calcineurin inhibitor nephrotoxicity is a main contributor to CKD after NKSOT, but other factors in the pretransplant, peritransplant, and post-transplant period can predispose to progressive kidney dysfunction. The management of CKD after NKSOT generally follows society guidelines for native kidney disease. Kidney-protective and calcineurin inhibitor-sparing immunosuppression has been explored in this population and warrants a discussion with transplant teams. Kidney transplantation in NKSOT recipients remains the kidney replacement therapy of choice for suitable candidates, as it provides a survival benefit over remaining on dialysis.

Management of Hepatorenal Syndrome: A Review

Acute kidney injury (AKI) occurs frequently in patients with cirrhosis, and hepatorenal syndrome (HRS) is second most common etiology of AKI after volume responsible pre-renal etiology. AKI in these patients negatively impacts pre- and post-transplant patient survival and healthcare burden. Reduced effective blood volume with consequent reduced renal blood flow, along with systemic inflammation in patients with decompensated cirrhosis, result in susceptibility to HRS. In this article, we will review updates over the last 5 years on the changing definition with diagnostic criteria and nomenclature of AKI and HRS, data on medical treatment with vasoconstrictors, and urinary biomarkers in diagnosis of etiology of AKI. We will also discuss the significance of liver transplantation evaluation once the diagnosis of HRS is established and the post-transplant immunosuppression management. We will also review one of the challenging issues that remains among transplant-eligible patients, that of allocation of simultaneous liver kidney transplant. Finally, we will review the new implemented policy from the Organ Procurement Transplant Network on simultaneous liver kidney allocation.

The Effect of Donor Age and Recipient Characteristics on Renal Outcomes in Patients Receiving Prolonged-Release Tacrolimus After Liver Transplantation: Post-Hoc Analyses of the DIAMOND Study

Background

The DIAMOND study of de novo liver transplant patients showed that prolonged-release tacrolimus exposure in the acute post-transplant period maintained renal function over 24 weeks of treatment. To assess these findings further, we performed a post-hoc analysis in patients according to baseline kidney function, Model for End-stage Liver Disease [MELD] scores, and donor age.

Material/Methods

Patients received prolonged-release tacrolimus (initial-dose, Arm 1: 0.2 mg/kg/day, Arm 2: 0.15–0.175 mg/kg/day, Arm 3: 0.2 mg/kg/day delayed until Day 5), mycophenolate mofetil and 1 steroid bolus. Arms 2 and 3 also received basiliximab. The recommended tacrolimus target trough levels to Day 42 post-transplantation were 5–15 ng/mL in all arms. In this post-hoc analysis, change in renal outcome, based on estimated glomerular filtration rate (eGFR), Modified Diet in Renal Disease-4 (MDRD4), values from baseline to Week 24 post-transplantation, were assessed according to baseline patient factors: eGFR (≥60 and <60 mL/min/1.73 m²), MELD score (<25 and ≥25) and donor age (<50 and ≥50 years).

Results

Baseline characteristics were comparable (Arms 1–3: n=283, n=287, n=274, respectively). Patients with baseline renal function, eGFR ≥60 mL/min/1.73 m², experienced a decrease in eGFR in all tacrolimus treatment arms. In patients with lower baseline renal function (eGFR <60 mL/min/1.73 m²), an advantage for renal function was observed with both the early lower-dose and delayed higher-dose tacrolimus regimens compared with the early introduction of higher-dose tacrolimus. At Week 24, renal function was higher in the early-lower tacrolimus arm with older donors, and the delayed higher-dose tacrolimus arm with younger donors, both compared with early higher-dose tacrolimus.

Conclusions

Pre-transplantation factors, such as renal function and donor age, could guide the choice of prolonged-release tacrolimus regimen following liver transplantation.

Underestimation of chronic renal dysfunction after liver transplantation: ICEBERG study

AIM: To compare prevalence of chronic renal dysfunction (CRD) according to serum creatinine (sCr) vs estimated glomerular filtration rate (eGFR) among maintenance liver transplant patients.

METHODS: The ICEBERG study was an observational, retrospective, cross-sectional, and multicenter study. Consecutive adult patients (aged 18 years or older) with liver transplantation (LT) performed at least two years previously were recruited. Multi-organ transplant recipients were excluded. Chronic renal dysfunction was defined according to sCr based criteria in routine clinical practice (≥ 2 mg/dL) and eGFR using MDRD-4 equation (< 60 mL/min per 1.73 m²). Agreement between sCr definition and eGFR assessment was evaluated using the Kappa index. Cox regression analysis was applied to identify predictive factors for developing CRD after LT.

RESULTS: A total of 402 patients were analyzed (71.6% males). Mean ± SD age at transplant was 52.4 ± 9.8 years. Alcoholic cirrhosis without hepatocellular carcinoma was the most common reason for LT (32.8%). Mean time since LT was 6.9 ± 3.9 years. Based on sCr assessment, 35.3% of patients (95%CI: 30.6-40.0) had CRD; 50.2% (95%CI: 45.3-55.1) according to eGFR. In 32.2% of cases, sCr assessment had underestimated CRD. Multivariate analysis showed the following factors associated with developing CRD: eGFR < 60 mL/min per 1.73 m² at three months post-transplant [hazard ratio (HR) = 4.76; 95%CI: 2.78-8.33; P < 0.0001]; calcineurin inhibitor use (HR = 2.31; 95%CI: 1.05-5.07; P = 0.0371); male gender (HR = 1.98; 95%CI: 1.09-3.60; P = 0.0260); and ≥ 10 years post-transplantation (HR = 1.95; 95%CI: 1.08-3.54; P = 0.0279).

CONCLUSION: Seven years after LT, CRD affected half our patients, which was underestimated by sCr. An eGFR < 60 mL/min per 1.73 m² three months post-LT was predictive of subsequent CRD.

Ethanol at low concentrations protects glomerular podocytes through alcohol dehydrogenase and 20-HETE

Clinical studies suggest cardiovascular and renal benefits of ingesting small amounts of ethanol. Effects of ethanol, role of alcohol dehydrogenase (ADH) or of 20-hydroxyeicosatetraenoic acid (20-HETE) in podocytes of the glomerular filtration barrier have not been reported. We found that mouse podocytes at baseline generate 20-HETE and express ADH but not CYP2e1. Ethanol at high concentrations altered the actin cytoskeleton, induced CYP2e1, increased superoxide production and inhibited ADH gene expression. Ethanol at low concentrations upregulated the expression of ADH and CYP4a12a. 20-HETE, an arachidonic acid metabolite generated by CYP4a12a, blocked the ethanol-induced cytoskeletal derangement and superoxide generation. Ethanol at high concentration or ADH inhibitor increased glomerular albumin permeability in vitro. 20-HETE and its metabolite produced by ADH activity, 20-carboxy-arachidonic acid, protected the glomerular permeability barrier against an ADH inhibitor, puromycin or FSGS permeability factor. We conclude that ADH activity is required for glomerular function, 20-HETE is a physiological substrate of ADH in podocytes and that podocytes are useful biosensors to understand glomeruloprotective effects of ethanol.

Chronic kidney disease and associated mortality after liver transplantation--a time-dependent analysis using measured glomerular filtration rate

BACKGROUND & AIMS

The accuracy of creatinine-based estimated GFR (eGFR) in assessing the prevalence of chronic kidney disease (CKD) and associated mortality after liver transplantation (LTx) is unknown. Using measured GFR (mGFR) by iothalamate clearance, we determined the prevalence of the entire spectrum of renal dysfunction and the impact of CKD on mortality after LTx.

METHODS

A database that prospectively tracks all LTx recipients at this academic transplant program from 1985 to 2012 was queried to identify all adult primary LTx recipients. Our post-LTx protocol incorporates GFR measurement by iothalamate clearance at regular intervals. A multistate model was used to assess the prevalence of CKD, kidney transplant, and death after LTx. Time-dependent Cox regression analysis was performed to evaluate the impact of mGFR and eGFR changes on survival.

RESULTS

A total of 1211 transplant recipients were included. At the time of LTx, the median age was 54 years, 60% were male and 86% were Caucasian. At 25 years after LTx, 54% of patients died, 9% underwent kidney transplantation, whereas 7%, 21%, and 18% had mGFR >60, 59-30, and <30 ml/min/1.73 m(2) respectively. The risk of death increased when mGFR decreased below 30 ml/min/1.73 m(2): HR = 2.67 (95% CI = 1.80-3.96) for GFR = 29-15 ml/min/1.73 m(2) and HR = 5.47 (95% CI = 3.10-9.65) for GFR <15 ml/min/1.73 m(2). Compared to mGFR, eGFR underestimated mortality risk in LTx recipients with an eGFR of 30-90 ml/min/1.73 m(2).

CONCLUSIONS

An overwhelming majority of LTx recipients develop CKD. The risk of death increases exponentially when GFR <30 ml/min/1.73 m(2). Creatinine-based eGFR underestimates the mortality risk in a large proportion of patients.

Chronic kidney disease after liver transplantation: pretransplantation risk factors and predictors during follow-up

BACKGROUND

Chronic renal impairment is an emerging problem in the management of patients after liver transplantation (LT).

METHODS

We prospectively analyzed predictors of chronic kidney disease (CKD) after LT in 179 patients followed for a median of 63 months. Diagnosis of CKD was based on an estimated glomerular filtration rate (GFR) of less than 60 mL/min according to the current position statement from the Kidney Disease Improving Global Outcome. Pretransplantation risk factors were evaluated. A Cox regression analysis, with time-dependent variables evaluated during follow-up, was applied to realize a prognostic model for CKD, and a prognostic index was also calculated. The validity of the model was tested in 149 independent LT patients with a median follow-up of 46 months.

RESULTS

The cumulative incidence of CKD was 45% at 5 years after LT. Estimated GFR at LT was the only pretransplantation independent risk factor (beta, 0.33; standard error (beta), 0.07; 95% confidence interval, 0.95-0.98). Development of arterial hypertension (hazards ratio [HR], 1.83), episodes of severe infection (HR, 2.15), and estimated GFR (HR, 0.89) after LT were identified as independent prognostic factors at the Cox regression time-dependent analysis. The model was able to identify the patients at higher risk for the development of CKD in the validation set.

CONCLUSIONS

Lower renal function at transplantation is associated with a higher risk of CKD after transplantation. A predictive model based on the variation of posttransplantation variables during the course of follow-up can help the clinicians to estimate the probability of CKD in the next 12 months.

Self-reported non-adherence to immune-suppressant therapy in liver transplant recipients: demographic, interpersonal, and intrapersonal factors

Adherence to immune suppressants and follow-up care regimen is important in achieving optimal long-term outcomes after organ transplantation. To identify patients most at risk for non-adherence, this cross-sectional, descriptive study explores the prevalence and correlates of non-adherence to immune-suppressant therapy among liver recipients. Anonymous questionnaires mailed consisted of the domains: (i) adherence barriers to immune suppressants, (ii) immune suppressants knowledge, (iii) demographics, (iv) social support, (v) medical co-morbidities, and (vi) healthcare locus of control and other beliefs. Overall response was 49% (281/572). Data analyzed for those transplanted within 10 yr of study reveal 50% (119/237) recipients or 9.2/100 person years reporting non-adherence. Non-adherence was reported highest in the 2-5 yr post-transplant phase (69/123, 56%). The highest immune-suppressant non-adherence rates were in recipients who are: divorced (26/34, 76%, p=0.0093), have a history of substance or alcohol use (42/69, 61%, p=0.0354), have mental health needs (50/84, 60%, p=0.0336), those who missed clinic appointments (25/30, 83%, p<0.0001), and did not maintain medication logs (71/122, 58%, p=0.0168). Respondents who were non-adherent with physician appointments were more than four and a half times as likely (OR 4.7, 95% CI 1.5-14.7, p=0.008) to be non-adherent with immune suppressants. In conclusion, half of our respondents report non-adherence to immune suppressants. Factors identified may assist clinicians to gauge patients' non-adherence risk and target resources.

Management of renal dysfunction in the liver transplant recipient

PURPOSE OF REVIEW

Acute and chronic kidney injury following orthotopic liver transplantation (OLT) is associated with increased morbidity and mortality. With the increasing longevity of liver transplant recipients, chronic kidney disease (CKD) has become an increasingly prevalent complication among long-term survivors. This article provides an overview of the literature on suggested risk factors for acute and CKD following OLT and a discussion of an approach to their medical management.

RECENT FINDINGS

In OLT candidates with pretransplant renal dysfunction, the use of interleukin-2 receptor blockers or antithymocyte globulin induction therapy in conjunction with delayed introduction of calcineurin inhibitors may preserve early renal function. In long-term stable OLT recipients with established calcineurin inhibitor nephrotoxicity, calcineurin inhibitor minimization or withdrawal protocols may halt or ameliorate renal dysfunction without compromising patient and graft survival. However, large-scale, multicenter, randomized controlled trials are still needed.

SUMMARY

The occurrence of acute kidney injury is common immediately after OLT, whereas the incidence of CKD and end-stage renal disease increases with time. Identifying patients at risk for acute kidney injury and CKD following OLT and early implementation of measures to preserve, halt, or ameliorate the progression of renal dysfunction should be an integral part in the management of OLT recipients.

Early Postoperative Renal Dysfunction in the Adult Living Donor Liver Transplantation

Living donor liver transplantation (LDLT) is a widely accepted treatment for end-stage liver diseases. Renal dysfunction, a frequent complication after liver transplantation, has an unfavorable effect on the prognosis. Despite special characteristics of LDLT, such as small-for-size graft syndrome (SFS), the relations between graft size and postoperative renal dysfunction have not been evaluated. So we described the relevance of previously known risk factors with SFS (graft-recipient body weight ratio [GRWR] < 0.8%) and early postoperative renal dysfunction in LDLT. The study population consisted of adults who received LDLT from May 1996 to November 2005. The 284 patients who were followed to 3 months after LDLT were classified as group I (n = 201, creatinine < 1.5 mg/dL) versus group II (n = 83, creatinine > or = 1.5 mg/dL). Univariate analysis showed renal dysfunction in the early postoperative period was related to preoperative total bilirubin, blood urea nitrogen, creatinine, prothrombin time level, model for end-stage liver disease (MELD) score, GRWR, presence of preoperative renal dysfunction, transfusion of packed red blood cell, fresh frozen plasma, cryoprecipitate, reoperation, and the need for renal replacement therapy (RRT). Upon multivariate analysis, MELD score, GRWR, preoperative renal dysfunction, and need for RRT were related to early postoperative renal dysfunction. In conclusion, there was a significant relationship between SFS (GRWR < 0.8) and early postoperative renal dysfunction.

Rates and Risk Factors for Nonadherence to the Medical Regimen After Adult Solid Organ Transplantation

BACKGROUND

Despite the impact of medical regimen nonadherence on health outcomes after organ transplantation, there is mixed and conflicting evidence regarding the prevalence and predictors of posttransplant nonadherence. Clinicians require precise information on nonadherence rates in order to evaluate patients' risks for this problem.

METHODS

A total of 147 studies of kidney, heart, liver, pancreas/kidney-pancreas, or lung/heart-lung recipients published between 1981 and 2005 were included in a meta-analysis. Average nonadherence rates were calculated for 10 areas of the medical regimen. Correlations between nonadherence and patient psychosocial risk factors were examined.

RESULTS

Across all types of transplantation, average nonadherence rates ranged from 1 to 4 cases per 100 patients per year (PPY) for substance use (tobacco, alcohol, illicit drugs), to 19 to 25 cases per 100 PPY for nonadherence to immunosuppressants, diet, exercise, and other healthcare requirements. Rates varied significantly by transplant type in two areas: immunosuppressant nonadherence was highest in kidney recipients (36 cases per 100 PPY vs. 7 to 15 cases in other recipients). Failure to exercise was highest in heart recipients (34 cases per 100 PPY vs. 9 to 22 cases in other recipients). Demographics, social support, and perceived health showed little correlation with nonadherence. Pretransplant substance use predicted posttransplant use.

CONCLUSIONS

The estimated nonadherence rates, overall and by transplant type, allow clinicians to gauge patient risk and target resources accordingly. Nonadherence rates in some areas--including immunosuppressant use--appear unacceptably high. Weak correlations of most patient psychosocial factors with nonadherence suggest that attention should focus on other classes of variables (e.g., provider-related and systems-level factors), which may be more influential.

Review article: medical management of the liver transplant recipient - a primer for non-transplant doctors

BACKGROUND

Survival 10 years after orthotopic liver transplantation now approaches 65%. Consequently, community doctors must manage the metabolic and neoplastic complications of orthotopic liver transplantation in an ageing population.

AIMS

To review common sources of morbidity and mortality in long-term orthotopic liver transplantation recipients, and to make evidence-based recommendations regarding their management.

METHODS

Pertinent studies and reviews were identified by literature search through PubMed. Where evidence-based recommendations could not be gleaned from the literature, expert opinion was obtained from syllabi of national meetings.

RESULTS

The two most common causes of morbidity and mortality in orthotopic liver transplantation recipients are atherosclerotic vascular disease and de novo malignancy. The pathogenesis of many complications begins before orthotopic liver transplantation, and many are potentially modifiable. Most complications, however, can be directly ascribed to immunosuppressive agents. Despite improvements in our understanding of the pathogenesis and epidemiology of the metabolic and neoplastic complications of orthotopic liver transplantation, remarkably few randomized-controlled studies exist to define their optimal management.

CONCLUSIONS

Orthotopic liver transplantation recipients experience and succumb to the same afflictions of old age as non-transplant patients, but with greater frequency and at an earlier age. Most recommendations regarding surveillance for, and treatment of, medical complications of orthotopic liver transplantation remain based upon expert opinion rather than evidence-based medicine.

Acute renal disease, as defined by the RIFLE criteria, post-liver transplantation

Acute renal failure (ARF) can complicate up to 60% of orthotopic liver transplants (OLT). The RIFLE criteria were developed to provide a consensus definition for acute renal disease in critically ill patients. Using the RIFLE criteria, we aimed to determine the incidence and risk factors for ARF and acute renal injury (ARI), and to evaluate the link with the outcomes, patient survival and length of hospital stay. Three hundred patients, who received 359 OLTs, were retrospectively analyzed. ARI and ARF occurred post 11.1 and 25.7% of OLTs, respectively. By multivariate analysis, ARI was associated with pre-OLT hypertension and alcoholic liver disease and ARF with higher pre-OLT creatinine, inotrope and aminoglycoside use. ARF, but not ARI, had an impact on 30-day and 1-year patient survival and longer length of hospital stay. ARI and ARF, as defined by the RIFLE criteria, are common complications of OLT, with distinct risk factors and ARF has serious clinical consequences. The development of a consensus definition is a welcome advance, however these criteria do need to be validated in large studies in a wide variety of patient populations.

Influence of Hepatitis C on Renal Function After Liver Transplantation

Liver transplantation (OLT) is often complicated by renal failure. Hepatitis C (HCV) is said to be a risk factor for renal failure after OLT, but few studies have analyzed this directly. We evaluated all patients who received a liver transplant from 1995 through 2003. There were 147 patients infected with HCV and 202 not infected. Patients with HCV were further divided into 114 patients with benign HCV and 33 patients with severe HCV defined by bridging fibrosis or cirrhosis. The groups were evaluated for the development of renal insufficiency defined as a creatinine above 1.8 mg/dL on three consecutive occasions or renal failure as defined by the need for dialysis or renal transplant. The incidence of renal failure in patients with HCV was 10.2% and in patients without HCV was 3.5% (P = .004). Patients with severe HCV had an incidence of 12.1% vs 9.7% for patients with mild HCV. The linear trend in renal failure from non-HCV to mild HCV to severe HCV was significant (P = .012). The incidence of renal insufficiency was 23.4% in patients with HCV and 14.9% in patients without HCV (P = .080). The incidence was 32.3% in patients with severe HCV and 20.6% in patients with mild HCV. The trend in renal insufficiency across the three groups was mildly significant (P = .042). On multivariate analysis, HCV was a risk factor for renal failure with a relative risk of 2.58 (P = .045). The study suggests that HCV and the severity of recurrent HCV are risk factors for renal dysfunction after liver transplantation.

Predictive factors for chronic renal failure one year after orthotopic liver transplantation

Chronic renal failure (CRF) is increasingly prevalent in solid-organ-transplant patients. This is in part related to the long-term use of calcineurin inhibitor (CNI) agents. However, in orthotopic liver-transplant (OLT) patients, the effects of superimposed hepatitis C virus (HCV)-related renal lesions could also be a factor. The aim of this cohort study (February 2000 to September, 2003) was to identify the predictive factors at one year post-transplantation for CRF in OLT patients associated with induction therapies. CRF was defined as having a creatinine clearance (CC) lower than 60 mL/min. Of the 97 transplants performed during that period, 72 were still functioning after one year. Of these, 33 patients (45.8%) had CRF. In univariate analysis, the predicting factors for CRF were recipient sex (female), initial liver disease (HCV-related cirrhosis), pre-transplant CC (<80 mL/mn), and post-transplant serum creatinine >130 micromol/L at day 3 and months (M) 1, 3, and 6. In multivariate analysis, the independent predictive factors for CRF included female sex [OR: 11.5 (2.3-58.3); p = 0.003], HCV infection [OR: 5.01 (1.1-22.7); p = 0.03], pre-OLT CC <80 mL/mn [OR: 5.4 (1.2-23.7); p = 0.025], and serum creatinine at M6 greater than 130 micromol/L [OR: 19.6 (3.7-102.5); p = 0.0004]. Among all of the predictive factors for post-OLT CRF, only one is modifiable: post-transplant serum creatinine, which could be, to some extent, related to the long-term use of CNIs.

Chronic kidney disease post-liver transplantation

BACKGROUND

Renal disease is a recognized complication of orthotopic liver transplantation (OLT). We aimed to determine the incidence of all stages of chronic kidney disease (CKD), as defined in the Kidney Disease Outcomes Quality Initiative Guidelines. We also wanted to determine the risk factors for development of CKD and its impact on patient survival.

METHODS

All patients who underwent cadaveric OLT, from January 1993 until July 2004, were analysed. The glomerular filtration rate (GFR) was determined using the equation developed by the Modification of Diet in Renal Disease Study. Thirty potential risk factors were examined by univariate and multivariate ordinal logistic regression analysis. Kaplan-Meier survival analysis, the log-rank test and Cox regression analysis were performed to evaluate the survival data.

RESULTS

A total of 230 patients were included (107 males and 123 females) with a mean age of 47.7 years (4.5-70.35). Mean follow-up was 5.57 years (0.53-16.5). The following was the 10 year cumulative incidence for each stage of CKD: 0/1, 9.61%; 2, 53.71%; 3, 56.77%; 4, 6.11%; 5, 2.62%. Female gender, age, pre-OLT proteinuria, lower GFR from 1 year and higher creatinine from 6 months were associated with progression of CKD. The use of tacrolimus had a favourable impact. A GFR <30 ml/min, the need for re-transplantation and fulminant hepatic failure were all associated with reduced patient survival.

CONCLUSIONS

Moderate CKD was very prevalent. We identified the risk factors for progression of CKD and also that severe CKD was associated with reduced patient survival.

Kidney dysfunction in the recipients of liver transplants

1. Pretransplant kidney function is an important predictor of posttransplant kidney function. 2. Chronic kidney disease is present in 20% of liver transplant recipients by 5 years. 3. Kidney function is impacted by pretransplant management of the consequences of the hepatorenal syndrome. 4. The use of calcineurin inhibitor (CNI)-based immunosuppression is an important factor in the development of chronic kidney disease, and the use of mycophenolic acid- or sirolimus-based immunosuppression with reduced-dose CNI may be of benefit.

Renal histopathological lesions after orthotopic liver transplantation (OLT)

Liver transplant recipients are at risk of chronic renal failure (CRF), customarily considered to be secondary to CsA/FK506 nephrotoxicity. We have examined renal biopsies from 26 liver transplant recipients with CRF. Before OLT, 5 patients had CRF, 8 were diabetic and 9 hypertensive. Renal biopsies were performed at a mean of 5 years after liver transplantation. Mean SCr was then 212 micromol/L, proteinuria was 1 g/24 h. Twelve patients were diabetic and 25 hypertensive. Histology revealed impressive renal destruction, with a mean of 45% interstitial fibrosis and 45% glomerular sclerosis. All biopsies showed severe arteriosclerosis. CRF can be attributed to four associated primary lesions: (i) specific chronic CsA/FK506 arteriolopathy; (ii) typical diabetic nephropathy; (iii) acute or chronic thrombotic microangiopathy attributed to CsA/FK506 or alpha-IFN and (iv) tubular changes related to administration of hydroxyethylstarch. At the end of the follow-up, after a mean of 6.4 years, 12 patients required dialysis, 13 had CRF and only 1 had normal renal function. Thus, CRF in OLT recipients is more complex than originally thought and should not be classified as anti-calcineurin nephrotoxicity without further investigations, including renal histology. These investigations have therapeutic potential, that is, they may lead to a more aggressive treatment of hypertension and/or diabetes.

Incidence and risk factors of renal dysfunction after liver transplantation in Korea

Renal dysfunction, one of the most common complications after liver transplantation, influences patient outcomes. Little is known, however, about it in Korea. The aims of this study were to determine the incidence and to identify the risk factors for renal dysfunction after liver transplantation. Sixty-two patients who survived over 6 months after transplantation were enrolled. Renal function was classified by creatinine clearance (Ccr, mL/min), which was estimated using the Cockcroft-Gault formula. Twenty-seven patients (44%) showed mild renal dysfunction (60 < or = Ccr < 90), and 27 patients (44%), moderate dysfunction (30 < or = Ccr < 60). The others were found to have normal function (Ccr > or = 90). None displayed severe dysfunction (Ccr < 30). Compared to a control group (Ccr > or = 60), the renal dysfunction group showed lower preoperative Ccr (91 +/- 28.6, 63 +/- 21.9, respectively, P < .01) and lower Ccr at 3 months after transplantation (72 +/- 17.1, 49 +/- 14.6, respectively, P < .05). Age, sex, immunosuppressive drug usage, serum tacrolimus levels, and the frequency of postoperative acute renal failure did not affect the postoperative renal dysfunction. Twenty-six patients received mycophenolate mofetil while reducing the dose of calcineurin inhibitors because of compromised renal function. With mycophenolate mofetil treatment, the renal function seemed to improve, although the difference was not statistically significant (P = .057). These data demonstrate that renal dysfunction is common after liver transplantation and that preoperative renal function is the important factor predicting postoperative renal dysfunction.

Post-liver transplant acute renal failure: factors predicting development of end-stage renal disease

BACKGROUND

Acute renal failure (ARF) occurs in 5-50% of patients undergoing orthotopic liver transplantation (OLT). The aim of this study was to determine factors that might predict the development of end stage renal disease (ESRD) in patients who had ARF after OLT.

METHODS

We studied all OLT recipients between 9/1/1988 through 12/31/2000.

RESULTS

A total of 1602 patients underwent OLT during the study period. About 350 patients (22%) developed ARF requiring dialysis post-operatively. One hundred and twenty-three (39.8%) died within a year after OLT. Median follow up was 5.8 yr (range 1-12 yr). Forty-three patients (23%) developed ESRD over median of 3.79 yr (range 1-8 yr). Multivariate logistic regression analysis revealed creatinine levels > 1.7 mg/dL at 1 yr (p < 0.001), cyclosporine as immunosuppression (p = 0.026), and the presence of diabetes pre-OLT (p < 0.001) to be associated with the development of ESRD. The development of ESRD did not decrease patient survival (p = 0.111). ESRD patients who received subsequent kidney transplantation had significantly improved survival rates (p = 0.005).

CONCLUSIONS

Serum creatinine levels at 1 yr, cyclosporine as immunosuppression, and the presence of diabetes pre-OLT are independent predictive factors for the development of ESRD. ESRD patients who received kidney transplantation had higher 10-yr survival rates when compared with patients maintained on dialysis.

Early kidney dysfunction post liver transplantation predicts late chronic kidney disease

BACKGROUND

Acute and chronic renal dysfunction (ARD, CRD) are common complications after liver transplantation and are associated with poor outcome.

METHODS

We reviewed the results of 181 liver transplants performed in our institution between January 1, 1998 and December 31, 2000 in which the recipients were alive with good liver function at the end of the follow-up period (mean 2.7 years). Renal dysfunction was defined as a serum creatinine (Cr) greater than or equal to 2 mg/dL in both acute and chronic settings.

RESULTS

The incidence of ARD during the first posttransplant week was 39.2% (n=71), whereas late CRD occurred in 6.0% (n=11) of the patients by the end of the follow-up period. Among the variables we examined for association with CRD, five factors were found to be statistically significant in univariate analysis: pretransplant diabetes (PRTDM) (0.000), Cr greater than or equal to 2 during the first postoperative week (0.003), posttransplant diabetes (POTDM) (0.014), age greater than 50 (0.025), and tacrolimus level greater than 15 ng/mL at postoperative day 15 (0.058). In binary logistic regression analysis, PRTDM (odds ratio [OR]=5.7, 95% confidence interval [CI]) and early postoperative ARD (OR=10.2 95% CI) remained consistently significant. Nine of 11 patients with CRD also had a history of ARD during the first postoperative week. These patients progressed to CRD despite the fact that seven of nine had normalized their renal function by day 90 posttransplant.

CONCLUSION

We suggest that a combination of events during the first postoperative week after liver transplant serve as a physiologic "stress test" for the kidneys. Patients who fail the test (peak Cr >/=2 mg/dL during the first postoperative week) as well as the patients with diabetes mellitus are at increased risk of CRD. In such cases, conversion to a less nephrotoxic regimen may be beneficial.

Independent risk factors and natural history of renal dysfunction in liver transplant recipients

Renal dysfunction is common after liver transplantation. However, there are only limited data on the predictors and natural history of renal dysfunction after liver transplantation. In this study, we determined independent predictors and the natural history of renal dysfunction in 172 consecutive liver transplant recipients. Survival and time to development of permanent renal dysfunction (renal dysfunction defined as a sustained decrease in estimated glomerular filtration rate (GFR) of > 30 mL/min/1.73 m(2) from baseline for at least 6 months, severe renal failure defined as absolute GFR <30 mL/min/1.73 m(2) for at least 6 months) were determined using the Kaplan-Meier method. Cox regression analysis was used to test the independent effect of a given set of variables on time to development of such an event. Nine percent of patients required immediate dialysis, 35% developed permanent renal dysfunction, and 7% developed severe renal failure. The rate of decline in renal dysfunction was maximal, 6.5 mL/min/1.73 m(2) /mo, at 1 month after liver transplantation. Pre-existing diabetes mellitus, major surgical infection, and waiting time on the transplant list were independent risk factors for immediate dialysis. Presence of serum creatinine > 1.2 mg/dL at any time before liver transplantation and a baseline GFR <70 mL/min/1.73 m(2) were independent predictors of permanent renal dysfunction. Diabetes mellitus, coronary artery disease, and primary graft nonfunction predicted the development of severe renal failure. GFR stabilized around 9 months, and presence of decreased GFR > 30mL/min/1.73 m(2) from baseline at 9 months predicted development of permanent renal dysfunction. An absolute GFR of <30mL/min/1.73 m(2) occurring as early as 3 months after liver transplantation predicted severe renal failure. Severe renal failure was associated with a significantly lower survival by Cox regression analysis. We have identified risk factors and the natural history of permanent renal dysfunction and severe liver failure in liver transplant recipients. These observations may be useful in the development of nonnephrotoxic immunosuppressive regimens for high-risk liver transplant recipients.

Impairment of renal function following liver transplantation

BACKGROUND

Although renal insufficiency following liver transplantation is not infrequent, only limited reports describe the incidence and progression of the kidney disease.

METHODS

This single-centre retrospective analysis after successful liver transplantation between January 1985 and March 2002 defined the baseline serum creatinine at 50 days after liver transplantation to represent the renal function. The primary end-point was an increase of serum creatinine by more than 50% above the baseline.

RESULTS

Long-term data were available for 162 patients (84 women, 78 men) who received 167 liver transplants. The median serum creatinine level at 50 days after liver transplantation was 1.0 mg/dL (range 0.5-3.5 mg/dL). The median serum creatinine increased to 1.2 mg/dL (0.4-9.8 mg/dL) at the end of follow-up. Six patients (4%) experienced end-stage renal failure. Forty-one patients (25%) showed a 50% increase in the serum creatinine. Kaplan-Meier analysis revealed that 43% and 48% of patients had a deterioration of renal function at 10 and 15 years after liver transplantation, respectively. Patients at risk showed an increase of serum creatinine by 0.25 mg/dL/y. Only the recipient age was an independent risk factor for deterioration of renal function.

CONCLUSIONS

Although there is a high risk for the impairment of renal function after liver transplantation, progression of renal disease is slow and rarely results in end-stage renal failure within 10-15 years. However, patients at risk should be identified early to prevent further decline in renal function.

Renal failure after liver transplantation: outcome after calcineurin inhibitor withdrawal

Chronic nephrotoxicity is one of the most serious side-effects of calcineurin inhibitor treatment and a factor in mortality and morbidity after liver transplantation. In our transplant centre, among patients who underwent a liver transplantation between January 1989 and December 2000, 14 liver graft recipients (6.86%) developed de novo severe renal dysfunction as defined by a serum creatinine concentration above 200 micromol/L. Renal biopsy was performed in nine cases and evidenced histological lesions compatible with chronic nephrotoxicity related to calcineurin inhibitor treatment. For nine patients, we report the results of a prospective non-randomized study consisting of cyclosporine or tacrolimus withdrawal associated with administration of mycophenolate mofetil or azathioprine. Despite this therapeutic modification, we did not observe a significant renal function improvement but on the other hand, there was no graft rejection.

Renal damage mediated by oxidative stress: a hypothesis of protective effects of red wine

Over the last decade, oxidative stress has been implicated in the pathogenesis of a wide variety of seemingly unrelated renal diseases. Epidemiological studies have documented an association of moderate wine consumption with a decreased risk of cardiovascular and neurological diseases; however, similar studies in the kidney are still lacking. The kidney is an organ highly vulnerable to damage caused by reactive oxygen species (ROS), likely due to the abundance of polyunsaturated fatty acids in the composition of renal lipids. ROS are involved in the pathogenic mechanism of conditions such as glomerulosclerosis and tubulointerstitial fibrosis. The health benefits of moderate consumption of red wine can be partly attributed to its antioxidant properties. Indeed, the kidney antioxidant defense system is enhanced after chronic exposure to moderate amounts of wine, a response arising from the combined effects of ethanol and the nonalcoholic components, mainly polyphenols. Polyphenols behave as potent ROS scavengers and metal chelators; ethanol, in turn, modulates the activity of antioxidant enzymes. Therefore, a hypothesis that red wine causes a decreased vulnerability of the kidney to the oxidative challenges could be proposed. This view is partly supported by direct evidences indicating that wine and antioxidants isolated from red wine, as well as other antioxidants, significantly attenuate or prevent the oxidative damage to the kidney. The present hypothesis paper provides a collective body of evidence suggesting a protective role of moderate wine consumption against the production and progression of renal diseases, based on the existing concepts on the pathophysiology of kidney injury mediated by oxidative stress.

Identification of patients best suited for combined liver-kidney transplantation: part II

Liver-kidney transplantation (LKT) should be reserved for those recipients with primary disease affecting both organs. However, increasing transplant list waiting times have increased the development and duration of acute renal failure before liver transplantation. Furthermore, the need for posttransplant calcineurin inhibitors can render healing from acute renal failure difficult. Because of the increasing requests for and controversy over the topic of a kidney with a liver transplant (OLT) when complete failure of the kidney is not known, the following article will review the impact of renal failure on liver transplant outcome, treatment of peri-OLT renal failure, rejection rates after LKT, survival after LKT, and information on renal histology and progression of disease into the beginnings of an algorithm for making a decision about combined LKT.

End-stage renal disease (ESRD) after orthotopic liver transplantation (OLTX) using calcineurin-based immunotherapy: risk of development and treatment

BACKGROUND

The calcineurin inhibitors cyclosporine and tacrolimus are both known to be nephrotoxic. Their use in orthotopic liver transplantation (OLTX) has dramatically improved success rates. Recently, however, we have had an increase of patients who are presenting after OLTX with end-stage renal disease (ESRD). This retrospective study examines the incidence and treatment of ESRD and chronic renal failure (CRF) in OLTX patients.

METHODS

Patients receiving an OLTX only from June 1985 through December of 1994 who survived 6 months postoperatively were studied (n=834). Our prospectively collected database was the source of information. Patients were divided into three groups: Controls, no CRF or ESRD, n=748; CRF, sustained serum creatinine >2.5 mg/dl, n=41; and ESRD, n=45. Groups were compared for preoperative laboratory variables, diagnosis, postoperative variables, survival, type of ESRD therapy, and survival from onset of ESRD.

RESULTS

At 13 years after OLTX, the incidence of severe renal dysfunction was 18.1% (CRF 8.6% and ESRD 9.5%). Compared with control patients, CRF and ESRD patients had higher preoperative serum creatinine levels, a greater percentage of patients with hepatorenal syndrome, higher percentage requirement for dialysis in the first 3 months postoperatively, and a higher 1-year serum creatinine. Multivariate stepwise logistic regression analysis using preoperative and postoperative variables identified that an increase of serum creatinine compared with average at 1 year, 3 months, and 4 weeks postoperatively were independent risk factors for the development of CRF or ESRD with odds ratios of 2.6, 2.2, and 1.6, respectively. Overall survival from the time of OLTX was not significantly different among groups, but by year 13, the survival of the patients who had ESRD was only 28.2% compared with 54.6% in the control group. Patients developing ESRD had a 6-year survival after onset of ESRD of 27% for the patients receiving hemodialysis versus 71.4% for the patients developing ESRD who subsequently received kidney transplants.

CONCLUSIONS

Patients who are more than 10 years post-OLTX have CRF and ESRD at a high rate. The development of ESRD decreases survival, particularly in those patients treated with dialysis only. Patients who develop ESRD have a higher preoperative and 1-year serum creatinine and are more likely to have hepatorenal syndrome. However, an increase of serum creatinine at various times postoperatively is more predictive of the development of CRF or ESRD. New strategies for long-term immunosuppression may be needed to decrease this complication.

Late mortality after orthotopic liver transplantation

BACKGROUND

Mortality within the first year after orthotopic liver transplantation (OLTx) is usually due to infection or allograft failure. Late complications leading to death after OLTx have not been extensively evaluated. The aim of this study was to determine the incidence of late mortality and to identify the most common causes and risk factors associated with late mortality after OLTx.

METHODS

A total of 479 OLTx were performed in 459 patients (320 males, 139 females; mean age 47 years, range 13 to 69) between September 1991 and April 2000. All patient deaths among liver transplant recipients who survived more than 1 year after transplantation (follow-up mean 3.4 years, median 3, range 1 to 8.6) were reviewed.

RESULTS

In all, 122 allografts (24%) were lost in 109 patients during the study period (24%). Seventy-five allografts were lost in 69 patients by 1 year (15%). Forty-seven allografts were lost in 40 patients who survived at least 1 year (9.6%). Actuarial survivals at 2 years, 5 years, and 9 years were 95%, 85%, and 80%, respectively (based on 100% survival at 1 year). The causes of the late mortality were malignancy (9 patients), disease recurrence (8), late infection (6), renal failure complications (5), cardiovascular complications (4), chronic rejection (3), gastrointestinal hemorrhage (2), medication noncompliance (1), and unknown (2).

CONCLUSIONS

Malignancy and disease recurrence are the major causes of late mortality among adult OLTx recipients. Pharmacologic immunosuppression is associated with many of the causes of late mortality. Advances in immunosuppression with less toxicity may improve long-term survival after OLTx.

Alcohol: role in the development of hypertension and end-stage renal disease

Alcohol is a common risk factor in the general population for a variety of health outcomes. In the present review, we discuss the recent literature on alcohol, hypertension, and renal disease. The regular consumption of more than two drinks per day is associated with both hypertension and renal disease. The mechanisms by which consumption of alcohol leads to hypertension and perhaps renal disease are unknown.

Posttransplantation dialysis-associated infections: morbidity and impact on outcome in liver transplant recipients

The aim of this study is to assess the predictors, impact on infectious morbidity, and outcome of posttransplantation dialysis in liver transplant recipients and to compare the results with data from patients who did not require dialysis after transplantation. The study sample included 176 consecutive patients undergoing liver transplantation; the median follow-up was 4.3 years. All patients were administered tacrolimus as primary immunosuppression. Overall, 16% (28 of 176 patients) of the patients required dialysis after transplantation. Patients requiring dialysis had significantly greater pretransplantation creatinine levels (2.4 v 1.2 mg/dL; P =.009), were more likely to require pretransplantation dialysis (21% v 1%; P =.0001), and had a greater rate of biopsy-proven rejection episodes (50%, 14 of 28 episodes v 20%, 30 of 148 episodes; P =.0009) and longer posttransplantation intensive care unit lengths of stay (P =.0001). The incidence of infections (91% v 41%; P =.0001) and episodes of infection per patient (2.4 v 0.7 episodes; P =.0001) were significantly greater in patients undergoing dialysis compared with those not undergoing dialysis. There was no difference in the frequency of cytomegalovirus (CMV) infection or disease; however, bacterial infections (87% v 31%; P =.0001) and invasive fungal infections (39% v 7%; P =.0001) were significantly more likely to occur in patients requiring dialysis. In logistic regression, dialysis (P =.0006) and CMV infection (P =.007) were independent significant predictors of major infections. Overall survival (assessed by Kaplan-Meier probability) was less in patients undergoing dialysis compared with those not undergoing dialysis (P =.0001). Among dialyzed patients, only 10% of those who survived had an invasive fungal infection compared with 46% of those who died (P =.08); 5 of 6 patients died within 1 month of the fungal infection. The need for dialysis portended a grave outcome in liver transplant recipients and identified a subgroup of patients at a significantly greater risk for major infections, particularly fungal infections, after liver transplantation.