Liver and intestine transplantation in the United States, 1996-2005

Are MELD and MELDNa Still Reliable Tools to Predict Mortality on the Liver Transplant Waiting List?

Liver transplantation is the only curative treatment for end-stage liver disease. Unfortunately, the scarcity of donor organs and the increasing pool of potential recipients limit access to this life-saving procedure. Allocation should account for medical and ethical factors, ensuring equal access to transplantation regardless of recipient's gender, race, religion, or income. Based on their short-term prognosis prediction, model for end-stage liver disease (MELD) and MELD sodium (MELDNa) have been widely used to prioritize patients on the waiting list for liver transplantation resulting in a significant decrease in waiting list mortality/removal. Recent concern has been raised regarding the prognostic accuracy of MELD and MELDNa due, in part, to changes in recipients' profile such as body mass index, comorbidities, and general condition, including nutritional status and cause of liver disease, among others. This review aims to provide a comprehensive view of the current state of MELD and MELDNa advantages and limitations and promising alternatives. Finally, it will explore future options to increase the donor pool and improve donor-recipient matching.

A Share 21 model in liver transplantation: Impact on waitlist outcomes

With the introduction of Model for End-Stage Liver Disease-Sodium (MELD-Na)-based allocation, the score at which patients benefit from liver transplantation (LT) has shifted from a score of 15 to 21. This study aimed to evaluate waitlist outcomes in patients with MELD-Na scores <21 and explore the utility of replacing "Share 15" with "Share 21." The study uses data from the Organ Procurement and Transplantation Network/United Network for Organ Sharing registry. All adult patients registered for LT after implementation of the MELD-Na-based allocation were evaluated. Waitlist patients with initial and final scores <21 were eligible. Patients with exception scores were excluded. To explore the potential impact of a Share 21 model, patients with an initial MELD-Na score of 6-14 (Group 1) and those with a score of 15-20 (Group 2) were compared for waitlist outcomes. There were 3686 patients with an initial score of 6-14 (Group 1) and 3282 with a score of 15-20 (Group 2). Group 2, when compared to Group 1, showed comparable risk of mortality (adjusted hazard ratio [aHR] 1.00, P = .97), higher transplant probability (aHR 3.25, P < .001), and lower likelihood of removal from listing because of improvement (aHR 0.74, P = .011). Share 21 may enhance transplant opportunities and increase parity for patients with higher MELD-Na scores without compromising waitlist outcomes.

Internal hernia of the small intestine around biliary catheter after living-donor liver transplantation: A case report

INTRODUCTION

Biliary reconstruction is a cornerstone of living-donor liver transplantation (LDLT). The routine uses of trans-anastomotic biliary catheters in biliary reconstruction had been a controversial issue. We describe a rare complication related to the use of trans-anastomotic biliary catheter after LDLT. In this case, intestinal obstruction occurred early after LDLT due to internal herniation of the small bowel around trans-anastomotic biliary catheter.

PRESENTATION

A 42 years male patient with end stage liver disease underwent LDLT utilizing a right hemi-liver graft. Biliary reconstruction was done by single duct-to-duct anastomosis over trans-anastomotic biliary catheter. The patient was doing well apart from early postoperative ascites that was managed medically. Three weeks after surgery, the patient developed severe agonizing central abdominal pain not responding to anti-spasmodics and analgesics. The decision was to proceed for surgical exploration. Exploration revealed internal herniation of the small bowel loops around the trans-anastomotic biliary catheter without strangulation. Reduction of the internal hernia was done by releasing the fixation of the biliary catheter from the anterior abdominal wall. Small bowel resection was not required. The patient had smooth postoperative course and was discharged 10 days after surgery.

DISCUSSION

Awareness regarding this rare complication plus early surgical intervention can prevent the development of postoperative morbidity and mortality. To the best of our knowledge this is the first report to describe such are complication after LDLT.

CONCLUSION

We report the first case of internal herniation of small bowel around biliary catheter early after LDLT.

Predictive Factors of Liver Dysfunction After Right Hemihepatectomy for Adult Living Donor Liver Transplantation

BACKGROUND

Living liver donors represent a special group of patients. They are healthy individuals who are exposed to a major surgery, in which the dominant liver proportion is extracted as a graft. Of all potential donor-related morbidities, posthepatectomy liver dysfunction (PHLD) is the most significant as it may be directly related to donor mortality. We aimed to review our data of adult living donor liver transplantation (LDLT) utilizing the right hemiliver grafts to determine the incidence and potential predictors for the development of PHLD, defined according to the International Study Group of Liver Surgery.

METHODS

We reviewed the data of all adult living donors who underwent right hemihepatectomy during the period between May 2004 and 2016.

RESULTS

During the study period, 434 cases underwent right hemihepatectomy for adult LDLT. We divided our cases into 2 groups according to the occurrence of PHLD. A significant lower residual liver volume and percentage were noted in PHLD group. Longer intensive care unit stay and hospital stay, and more postoperative morbidities, were observed in PHLD group. PHLD occurred in 50 cases (11.5%), and most of them were grade A (47 cases [10.8%]). Two cases (0.5%) had grade B requiring diuretic therapy, and 1 case (0.2%) had grade C requiring ultrasound guided tube drainage and surgical exploration finally.

CONCLUSIONS

We should not underestimate the risks of liver donation surgery, especially when utilizing the right hemiliver graft. Donor safety should be ensured by accurate preoperative volumetric assessment of the remnant liver and remnant liver volume limitations must be strictly followed.

Living-Donor Liver Transplantation in Hepatitis C Virus Era: A Report of 500 Consecutive Cases in a Single Center

BACKGROUND

Living donor liver transplantation (LDLT) is considered a safe alternative to deceased donor liver transplantation (DDLT). In Egypt, DDLT program is still awaited, making LDLT the only hope for patients with end-stage liver disease, mainly due to chronic hepatitis C virus (HCV) infection. The current study is conducted to evaluate our experience of LDLT and discuss the lessons learned from 500 consecutive cases in HCV area.

METHODS

We reviewed the data of patients who underwent LDLT at Gastrointestinal Surgery Center, Mansoura University during the period between May 2004 and March 2017.

RESULTS

During the study period, 500 cases underwent LDLT at our unit. The median age was 51 years, and most of our cases were males (446, 89.2%) and had HCV infection (453, 90.6%). The median MELD score was 15. Median ICU stay was 5 days, and hospital stay was 22 days. Postoperative morbidities occurred in 220 cases (44%). Early mortality occurred in 69 patients (13.8%), and late mortality occurred in 45 patients (9%). The 1-, 3-, 5-, and 7-year overall survival rates of all cases were 80.9%, 78.2%, 75.7%, and 75%, respectively. Preoperative creatinine, worm ischemia, blood transfusion, ICU stay, postoperative morbidities, and small for size syndrome were independent predictors for overall survival.

CONCLUSIONS

In countries lacking DDLT, LDLT is the only effective alternative. LDLT requires a teamwork to achieve successful outcomes. LDLT should only be performed in centers with the adequate experience to avoid and decrease the hazards related to this procedure.

Antibody-Mediated Rejection After Liver Transplant

Antibody-mediated rejection (AMR) in liver transplants is a field in its infancy compared with its allograft cohorts of the kidney and lung. Acute AMR is diagnosed based on specific clinical and histopathologic criteria: serum donor specific antibodies, C4d staining, histopathologic findings on liver biopsy, and exclusion of other entities. In contrast, the histologic features of chronic AMR are not as specific and it is a more challenging diagnosis to make. Treatments of acute and chronic AMR include some combination of steroids, immune-modulating agents, intravenous immunoglobulin, plasmapheresis, and proteasome inhibitors.

Drug Metabolism, Drug Interactions, and Drug-Induced Liver Injury in Living Donor Liver Transplant Patients

Living donor liver transplant (LDLT) fills a critically needed gap in the number of livers available for transplant. However, little is known about the functional recovery of the liver in the donor and in the recipient after surgery. Given that both donor and recipients are treated with several drugs, it is important to characterize the time course of recovery of hepatic synthetic, metabolic, and excretory function in these patients. In the absence of data from LDLT, information on the effect of liver disease on the pharmacokinetics of medications can be used as guidance for drug dosing in LDLT patients.

Endoscopic Management of Biliary Leaks and Strictures After Living Donor Liver Transplantation: Optimizing Techniques for Successful Management

BACKGROUND AND AIMS

Biliary complications (BCs) occur in up to 40% of living donor liver transplant (LDLT) recipients. The aim of this study was to evaluate the efficacy of endoscopic therapy in the management of LDLT-related BCs.

METHODS

A retrospective study of 100 LDLT recipients at a single transplant center over a 9-year period was conducted. BC was defined as a biliary leak and/or a stricture. Patient records were used to identify time to diagnosis, type of intervention, and time to resolution.

RESULTS

BCs occurred in 46 (46%) patients; median follow-up was 4.6 years (range 5 days-9.3 years); and median time to diagnosis was 37.5 days (range 1 day-3.5 years). BCs were classified as a leak in 6 (6%), stricture in 22 (22%), and a leak + stricture in 18 (18%). ERCP was the initial treatment modality in 43/46 (93%) patients and was completed in 42/43 (98%). Three (6.5%) patients with a leak underwent surgery as the primary treatment approach. The median time to resolution of BCs was 91.5 days (range 21-367). Thirteen patients had a recurrence which was managed with endoscopic therapy alone.

CONCLUSIONS

Endoscopic therapy was successful in almost all patients (98%) and ERCP alone resulted in successful treatment in a higher proportion of patients (93%) than traditionally reported. Advanced endoscopic techniques obviate the need for PTC and/or surgery and allow successful management in almost all LDLT recipients presenting with BC and in patients with recurrence of strictures.

Predicting renal recovery after liver transplant with severe pretransplant subacute kidney injury: The impact of warm ischemia time

Identifying which liver transplantation (LT) candidates with severe kidney injury will have a full recovery of renal function after liver transplantation alone (LTA) is difficult. Avoiding unnecessary simultaneous liver-kidney transplantation (SLKT) can optimize the use of scarce kidney grafts. Incorrect predictions of spontaneous renal recovery after LTA can lead to increased morbidity and mortality. We retrospectively analyzed all LTA patients at our institution from February 2002 to February 2013 (n = 583) and identified a cohort with severe subacute renal injury (n = 40; creatinine <2 mg/dL in the 14-89 days prior to LTA and not on renal replacement therapy [RRT] yet, ≥2 mg/dL within 14 days of LTA and/or on RRT). Of 40 LTA recipients, 26 (65%) had renal recovery and 14 (35%) did not. The median (interquartile range) warm ischemia time (WIT) in recipients with and without renal recovery after LTA was 31 minutes (24-46 minutes) and 39 minutes (34-49 minutes; P = 0.02), respectively. Adjusting for the severity of the subacute kidney injury with either Acute Kidney Injury Network or Risk, Injury, Failure, Loss, and End-Stage Kidney Disease criteria, increasing WIT was associated with lack of renal recovery (serum creatinine <2 mg/dL after LTA, not on RRT), with an odds ratio (OR) of 1.08 (1.01-1.16; P = 0.03) and 1.09 (1.01-1.17; P = 0.02), respectively. For each minute of increased WIT, there was an 8%-9% increase in the risk of lack of renal recovery after LTA. In a separate cohort of 98 LTA recipients with subacute kidney injury, we confirmed the association of WIT and lack of renal recovery (OR, 1.04; P = 0.04). In LT candidates with severe subacute renal injury, operative measures to minimize WIT may improve renal recovery potentially avoiding RRT and the need for subsequent kidney transplant. Liver Transplantation 22 1085-1091 2016 AASLD.

Pharmacokinetics of drugs in adult living donor liver transplant patients: regulatory factors and observations based on studies in animals and humans

INTRODUCTION

Limited information is available on the pharmacokinetics of drugs in the donors and recipients following adult living donor liver transplantation (LDLT). Given that both the donors and recipients receive multiple drug therapies, it is important to assess the pharmacokinetics of drugs used in these patients.

AREAS COVERED

Pathophysiological changes that occur post-surgery and regulatory factors that may influence pharmacokinetics of drugs, especially hepatic drug metabolism and transport in both LDLT donors and the recipients are discussed. Pharmacokinetic data in animals with partial hepatectomy are presented. Clinical pharmacokinetic data of certain drugs in LDLT recipients are further reviewed.

EXPERT OPINION

It takes up to six months for the liver volume to return to normal after LDLT surgery. In the LDLT recipients, drug exposure generally is higher with lower clearance during early period post-transplant; lower initial dosages of immunosuppressants are used than deceased donor liver transplant recipients during the first six months post-transplantation. In animals, the activities of hepatic drug metabolizing enzymes and transporters are known to be altered differentially during liver regeneration. Future studies on the actual hepatic function with reference to drug metabolism, drug transport, and biliary secretion in both LDLT donors and recipients are required.

One Size Does Not Fit All--Regional Variation in the Impact of the Share 35 Liver Allocation Policy

Allocation policies for liver transplantation underwent significant changes in June 2013 with the introduction of Share 35. We aimed to examine the effect of Share 35 on regional variation in posttransplant outcomes. We examined two patient groups from the United Network for Organ Sharing dataset; a pre-Share 35 group composed of patients transplanted between June 17, 2012, and June 17, 2013 (n = 5523), and a post-Share group composed of patients transplanted between June 18, 2013, and June 18, 2014 (n = 5815). We used Kaplan-Meier and Cox multivariable analyses to compare survival. There were significant increases in allocation Model for End-stage Liver Disease (MELD) scores, laboratory MELD scores, and proportions of patients in the intensive care unit and on mechanical, ventilated, or organ-perfusion support at transplant post-Share 35. We also observed a significant increase in donor risk index in this group. We found no difference on a national level in survival between patients transplanted pre-Share 35 and post-Share 35 (p = 0.987). Regionally, however, posttransplantation survival was significantly worse in the post-Share 35 patients in regions 4 and 10 (p = 0.008 and p = 0.04), with no significant differences in the remaining regions. These results suggest that Share 35 has been associated with transplanting "sicker patients" with higher MELD scores, and although no difference in survival is observed on a national level, outcomes appear to be concerning in some regions.

Employment after liver transplantation: a review

BACKGROUND

Return to productive employment is often an important milestone in the recovery and rehabilitation process after liver transplantation (OLT). This literature review identifies factors associated with employment in patients who underwent OLT.

METHODS

We searched PubMed for articles that addressed the various factors affecting employment after OLT.

RESULTS

The studies demonstrated improvement in the quality of life and examined factors that predicted whether patients would return to work after OLT. Demographic variable associated with posttransplant employment included young age, male sex, college degree, Caucasian race, and pretransplant employment. Patients with alcohol-related liver disease had a significantly lower rate of employment than did those with other etiologies of liver disease. Recipients who were employed after transplantation had a significantly better posttransplant functional status than did those who were not employed.

CONCLUSION

Economic pressures are increasing the expectation that patients who undergo successful OLT will return to work. Thus, transplant teams need to have a better understanding of posttransplant work outcomes for this vulnerable population, and greater attention must be paid to the full social rehabilitation of transplant recipients. Specific interventions for OLT recipients should be designed to evaluate and change their health perceptions and encourage their return to work.

The role of adult living donor liver transplantation and recent advances

Twenty years since the first cases were described, adult living donor liver transplantation (ALDLT) is now considered a valid option to expand the donor pool in view of the ongoing shortage of organs and the high waiting list mortality rate. Despite the rapid evolution and acceptance of this complex process of donation and transplantation in clinical practice, the indications, outcome, ethical considerations and quality and safety aspects continue to evolve based on new data from large cohort studies. This article reviews the surgical and clinical advances in the field of liver transplantation, focusing on technical refinements and discussing the issues that may lead to a further expansion of this complex surgical procedure and the role of ALDLT.

Retrospective cohort study of liver transplantation in the United Kingdom between 1994 and 2010: the impact of hepatitis C infection

BACKGROUND

Liver transplantation is an important and established treatment option for chronic hepatitis C virus (HCV) related end-stage liver disease (HCV-related ESLD). This study describes trends in elective liver transplantation among persons with HCV-related ESLD.

STUDY DESIGN

Retrospective cohort.

METHODS

Analyses of United Kingdom (UK) Transplant Registry data for the period 1994 to 2010, with follow-up information extending to 2011.

RESULTS

Annual registrations for liver transplantation increased linearly and alcoholic liver cirrhosis (2075, 24%) and HCV-related ESLD (1213, 14%) were the most common indications. HCV-related ESLD patients were mainly aged 40-49 years (32%) and 50-59 years (43%); males (76%); and of white ethnicity (74%). Overall, 75% (956/1213) received a liver transplant with a linear increase over the period (OR 1.11, 95% CI 1.08, 1.13). Pre transplant mortality was unchanged (adjusted OR 1.0, 95% CI 0.96, 1.05) and post-transplant mortality decreased in both HCV-related (adjusted OR 0.77, 95% CI 0.68, 0.88) and non-HCV-related ESLD (adjusted OR 0.82, 95% CI 0.75, 0.89) patients.

CONCLUSION

The increase in demand for and receipt of liver transplants among persons with HCV-related ESLD requires coordinated efforts to increase not only organ donation, but investment in HCV prevention programmes and improved access to hepatitis C treatment services.

Assessing variation in the costs of care among patients awaiting liver transplantation

Previous economic analyses of liver transplantation have focused on the cost of the transplant and subsequent care. Accurate characterization of the pretransplant costs, indexed to severity of illness, is needed to assess the economic burden of liver disease. A novel data set linking Medicare claims with transplant registry data for 15,710 liver transplant recipients was used to determine average monthly waitlist spending (N = 249,434 waitlist months) using multivariable linear regression models to adjust for recipient characteristics including Model for End-Stage Liver Disease (MELD) score. Characteristics associated with higher spending included older age, female gender, hepatocellular carcinoma, diabetes, hypertension and increasing MELD score (p < 0.05 for all). Spending increased exponentially with severity of illness: expected monthly spending at a MELD score of 30 was 10 times higher than at MELD of 20 ($22,685 vs. $2030). Monthly spending within MELD strata also varied geographically. For candidates with a MELD score of 35, spending varied from $19,548 (region 10) to $36,099 (region 7). Regional variation in waitlist costs may reflect the impact of longer waiting times on greater pretransplant hospitalization rates among high MELD score patients. Reducing the number of high MELD waitlist patients through improved medical management and novel organ allocation systems could decrease total spending for end-stage liver care.

Incidence of death and potentially life-threatening near-miss events in living donor hepatic lobectomy: a world-wide survey

The incidence of morbidity and mortality after living donor liver transplantation (LDLT) is not well understood because reporting is not standardized and relies on single-center reports. Aborted hepatectomies (AHs) and potentially life-threatening near-miss events (during which a donor's life may be in danger but after which there are no long-term sequelae) are rarely reported. We conducted a worldwide survey of programs performing LDLT to determine the incidence of these events. A survey instrument was sent to 148 programs performing LDLT. The programs were asked to provide donor demographics, case volumes, and information about graft types, operative morbidity and mortality, near-miss events, and AHs. Seventy-one programs (48%), which performed donor hepatectomy 11,553 times and represented 21 countries, completed the survey. The average donor morbidity rate was 24%, with 5 donors (0.04%) requiring transplantation. The donor mortality rate was 0.2% (23/11,553), with the majority of deaths occurring within 60 days, and all but 4 deaths were related to the donation surgery. The incidences of near-miss events and AH were 1.1% and 1.2%, respectively. Program experience did not affect the incidence of donor morbidity or mortality, but near-miss events and AH were more likely in low-volume programs (≤50 LDLT procedures). In conclusion, it appears that independently of program experience, there is a consistent donor mortality rate of 0.2% associated with LDLT donor procedures, yet increased experience is associated with lower rates of AH and near-miss events. Potentially life-threatening near-miss events and AH are underappreciated complications that must be discussed as part of the informed consent process with any potential living liver donor.

Clinical applications of the Model for End-Stage Liver Disease (MELD) in hepatic medicine

The Model for End-Stage Liver Disease (MELD) score incorporates serum bilirubin, creatinine, and the international normalized ratio (INR) into a formula that provides a continuous variable that is a very accurate predictor of 90-day mortality in patients with cirrhosis. It is currently utilized in the United States to prioritize deceased donor organ allocation for patients listed for liver transplantation. The MELD score is superior to other prognostic models in patients with end-stage liver disease, such as the Child-Turcotte-Pugh score, since it uses only objective criteria, and its implementation in 2002 led to a sharp reduction in the number of people waiting for liver transplant and reduced mortality on the waiting list without affecting posttransplant survival. Although mainly adopted for use in patients waiting for liver transplant, the MELD score has also proved to be an effective predictor of outcome in other situations, such as patients with cirrhosis going for surgery and patients with fulminant hepatic failure or alcoholic hepatitis. Several variations of the original MELD score, involving the addition of serum sodium or looking at the change in MELD over time, have been examined, and these may slightly improve its accuracy. The MELD score does have limitations in situations where the INR or creatinine may be elevated due to reasons other than liver disease, and its implementation for organ allocation purposes does not take into consideration several conditions that benefit from liver transplantation. The application of the MELD score in prioritizing patients for liver transplantation has been successful, but further studies and legislation are required to ensure a fair and equitable system.

Long-term outcome of conversion to sirolimus monotherapy after liver transplant

OBJECTIVES

This study sought to assess the long-term efficacy and safety of conversion from a calcineurin inhibitor-based immunosuppressive regimen to sirolimus monotherapy in liver transplant recipients with renal dysfunction.

MATERIALS AND METHODS

Twenty-five liver transplant recipients with calcineurin inhibitor-based immunosuppression were included in this single-center, prospective study. Indications were renal dysfunction, avoidance of tumor recurrence, combination renal dysfunction and avoidance of tumor recurrence, and calcineurin inhibitor-related adverse effects.

RESULTS

Mean interval between liver transplant and initiation of sirolimus monotherapy was 51.7 months. The mean follow-up was 75.6 months. The mean ± SD sirolimus whole-blood trough level was 9.0 ± 2.8 ng/mL after 6 months and 6.0 ± 1.8 ng/mL after 18 months. No rejection episodes occurred. There was an improvement of the mean creatinine level: 156.1 ± 54.9 μmol/L before conversion versus 129.1 ± 34.7 μmol/L approximately 3 years after conversion (P < .05). The glomerular filtration rate, measured by technetium Tc-99m-diethylenetriamine penta-acetic aerosol scintigraphy, improved from 27.4 ± 6.8 mL/min/1.73 m(2) before conversion to 43.3 ± 6.3 mL/min/1.73 m(2) at final follow-up. Proteinuria increased after conversion to sirolimus after 6 months (P < .05) and at last follow-up. The systolic blood pressure decreased from 151.5 ± 20.2 to 132.1 ± 19.4 mm Hg, and the diastolic from 89.7 ± 11.2 to 82.1 ± 9.1 mm Hg at last follow-up. Serum cholesterol and serum triglyceride levels were nearly unchanged. However, 50% of the patients were treated with lipid-lowering agents. Four patients had sirolimus-induced adverse effects (thrombocytopenia, gingival hyperplasia, oral ulceration).

CONCLUSIONS

Conversion from calcineurin inhibitors to sirolimus monotherapy after liver transplant results in stabilization of renal function in 75% to 85% of cases and of blood pressure, without increased risk of rejection. The spectrum of adverse effects is low.

Liver transplantation for hepatitis C from donation after cardiac death donors: an analysis of OPTN/UNOS data

Donation after cardiac death (DCD) liver transplantation is increasing largely because of a shortage of organs. However, there are almost no data that have specifically assessed the impact of using DCD livers for HCV patients. We retrospectively studied adult primary DCD liver transplantation (630 HCV, 1164 non-HCV) and 54 129 donation after brain death (DBD) liver transplantation between 2002 and 2009 using the UNOS/OPTN database. With donation after brain death (DBD) livers, HCV recipients had significantly inferior graft survival compared to non-HCV recipients (p < 0.0001). Contrary to DBD donors, DCD livers used in HCV patients showed no difference in graft survival compared to non-HCV patients (p = 0.5170). Cox models showed DCD livers and HCV disease had poorer graft survival (HR = 1.80 and 1.28, p < 0.0001, respectively). However, the hazard ratio of DCD and HCV interaction was 0.80 (p = 0.02) and these results suggest that DCD livers on HCV disease do not fare worse than DCD livers on non-HCV disease. The graft survival of recent years (2006-2009) was significantly better than that in former years (2002-2005) (p = 0.0482). In conclusion, DCD liver transplantation for HCV disease showed satisfactory outcomes. DCD liver transplantation can be valuable option for HCV related end-stage liver disease.

Simultaneous liver-kidney versus liver transplantation alone in patients with end-stage liver disease and kidney dysfunction not on dialysis

BACKGROUND

Since implementation of the Model for End-stage Liver Disease (MELD), the number of simultaneous liver-kidney transplantations (SLKT) has increased in the United States. However, predictors and survival benefit of SLKT compared to liver transplantation alone (LTA) are not well defined.

METHODS

Organ Procurement and Transplantation Network data of patients with end-stage liver disease (ESLD) with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) who had not been on dialysis while on the waiting list and underwent liver transplantation between 2002 and 2008 were analyzed. To identify predictors of undergoing SLKT versus LTA, multiple logistic regression analysis was performed. Cox proportional hazards regression analysis was used to assess the association between SLKT and post-liver transplant patient and graft survival.

RESULTS

The study cohort comprised 5443 patients; 262 (5%) underwent SLKT and 5181 (95%) underwent LTA. Adjusting for potential confounders, patients who underwent SLKT were 34% less likely to die after liver transplantation than those who underwent LTA (hazard ratio [HR] = 0.66, P = .012) and 33% less likely to have liver graft failure than those who underwent LTA (HR = 0.67, P = .010). Among those who underwent SLKT, 1-, 3-, and 5-year kidney graft survival probabilities were 88%, 80%, and 77%, respectively. Black race and diabetes were associated with a higher likelihood of SLKT versus LTA; female sex, a higher eGFR, and higher MELD score reduced the likelihood of SLKT.

CONCLUSIONS

Among those with ESLD and kidney dysfunction not on dialysis, post-liver transplant patient and liver graft survivals of patients who underwent SLKT were superior to those of patients who underwent LTA. Whether this reflects differences in the two groups that could not be adjusted in survival models or a specific effect of kidney dysfunction cannot be established.

Substance use by liver transplant candidates: an anonymous urinalysis study

Toxicological urinalysis is a highly sensitive and specific test that detects recent substance use. It has been established for substance misuse treatment but has not been routinely used at liver transplantation (LT) centers. Patients with a history of substance misuse are required to be abstinent from alcohol and illicit drugs before they are listed for LT. In this cross-sectional study, we sought to determine the prevalence of recent substance use in LT candidates via toxicological urinalysis. One hundred nine adults who were admitted for an LT assessment provided data, and they were categorized by the etiology of their liver disease [alcohol-related liver disease (ALD), hepatitis C virus (HCV), or other liver diseases]. Urine was toxicologically screened for drugs and their metabolites as well as the urinary alcohol metabolites ethyl glucuronide and ethyl sulfate. The prevalence of alcohol metabolites in patients with ALD was 20%. Licit and illicit substances together provided a positive toxicological result in 30% of the patients. Positive results were more common among patients with HCV (40%) and ALD (38%) versus patients with other liver diseases (18%). During the clinical assessment, 4% of the patients with ALD or HCV self-reported current alcohol or illicit drug use. These results correspond to the findings of other studies and emphasize the uncertainty of self-reported substance use data for LT candidates.

Evidence-based development of liver allocation: a review

Liver transplantation has undergone a rapid evolution from a high-risk experimental procedure to a mainstream therapy for thousands of patients with a wide range of hepatic diseases. Its increasing success has been accompanied by progressive imbalance between organ donor supply and the patients who might benefit. Where demand outstrips supply in transplantation, a system of organ allocation is inevitably required to make the wisest use of the available, but scarce, organs. Early attempts to rationally allocate donor livers were particularly hampered by lack of available and suitable data, leading to imperfect solutions that created or exacerbated inequities in the system. The advent and maturation of evidence-based predictors of waiting list mortality risk led to more objective criteria for liver allocation, aided by the increasing availability of data on large numbers of patients. Until now, the vast majority of allocation systems for liver transplantation have relied on estimation of waiting list mortality. Evidence-based allocation systems that incorporate measures of post-transplant outcomes are conceptually attractive and these transplant benefit-based allocation systems have been developed, modeled, and subjected to computer simulation. Future implementations of benefit-based liver allocation await continued refinement and additional debate in the transplant community.

Kidney function: glomerular filtration rate measurement with MR renography in patients with cirrhosis

PURPOSE

To assess the accuracy of glomerular filtration rate (GFR) measurements obtained with low-contrast agent dose dynamic contrast material-enhanced magnetic resonance (MR) renography in patients with liver cirrhosis who underwent routine liver MR imaging, with urinary clearance of technetium 99m ((99m)Tc) pentetic acid (DTPA) as the reference standard.

MATERIALS AND METHODS

This HIPAA-compliant study was institutional review board approved. Written informed patient consent was obtained. Twenty patients with cirrhosis (14 men, six women; age range, 41-70 years; mean age, 54.6 years) who were scheduled for routine 1.5-T liver MR examinations to screen for hepatocellular carcinoma during a 6-month period were prospectively included. Five-minute MR renography with a 3-mL dose of gadoteridol was performed instead of a routine test-dose timing examination. The GFR was estimated at MR imaging with use of two kinetic models. In one model, only the signal intensities in the aorta and kidney parenchyma were considered, and in the other, renal cortical and medullary signal intensities were treated separately. The GFR was also calculated by using serum creatinine levels according to the Cockcroft-Gault and modification of diet in renal disease (MDRD) formulas. All patients underwent a (99m)Tc-DTPA urinary clearance examination on the same day to obtain a reference GFR measurement. The accuracies of all MR- and creatinine-based GFR estimations were compared by using Wilcoxon signed rank tests.

RESULTS

The mean reference GFR, based on (99m)Tc-DTPA clearance, was 74.9 mL/min/1.73 m(2) ± 27.7 (standard deviation) (range, 10.3-120.7 mL/min/1.73 m(2)). With both kinetic models, 95% of MR-based GFRs were within 30% of the reference values, whereas only 40% and 60% of Cockcroft-Gault- and MDRD-based GFRs, respectively, were within this range. MR-based GFR estimates were significantly more accurate than creatinine level-based estimates (P < .001).

CONCLUSION

GFR assessment with MR imaging, which outperformed the Cockcroft-Gault and MDRD formulas, adds less than 10 minutes of table time to a clinically indicated liver MR examination without ionizing radiation.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101338/-/DC1.

The interaction among donor characteristics, severity of liver disease, and the cost of liver transplantation

Accurate assessment of the impact of donor quality on liver transplant (LT) costs has been limited by the lack of a large, multicenter study of detailed clinical and economic data. A novel, retrospective database linking information from the University HealthSystem Consortium and the Organ Procurement and Transplantation Network registry was analyzed using multivariate regression to determine the relationship between donor quality (assessed through the Donor Risk Index [DRI]), recipient illness severity, and total inpatient costs (transplant and all readmissions) for 1 year following LT. Cost data were available for 9059 LT recipients. Increasing MELD score, higher DRI, simultaneous liver-kidney transplant, female sex, and prior liver transplant were associated with increasing cost of LT (P < 0.05). MELD and DRI interact to synergistically increase the cost of LT (P < 0.05). Donors in the highest DRI quartile added close to $12,000 to the cost of transplantation and nearly $22,000 to posttransplant costs in comparison to the lowest risk donors. Among the individual components of the DRI, donation after cardiac death (increased costs by $20,769 versus brain dead donors) had the greatest impact on transplant costs. Overall, 1-year costs were increased in older donors, minority donors, nationally shared organs, and those with cold ischemic times of 7-13 hours (P < 0.05 for all). In conclusion, donor quality, as measured by the DRI, is an independent predictor of LT costs in the perioperative and postoperative periods. Centers in highly competitive regions that perform transplantation on higher MELD patients with high DRI livers may be particularly affected by the synergistic impact of these factors.

Diagnosis and management of chronic liver disease in older people

Chronic liver disease is increasingly prevalent and, as the population ages, geriatricians will see an increasing burden. We present an overview of the investigation and management of older adults with chronic parenchymal liver disease and highlight the potential roles of transjugular intrahepatic portosytemic shunts and orthotopic liver transplantation.

Short bowel syndrome

The short bowel syndrome (SBS) is a state of malabsorption following intestinal resection where there is less than 200 cm of intestinal length. The management of short bowel syndrome can be challenging and is best managed by a specialised multidisciplinary team. A good understanding of the pathophysiological consequences of resection of different portions of the small intestine is necessary to anticipate and prevent, where possible, consequences of SBS. Nutrient absorption and fluid and electrolyte management in the initial stages are critical to stabilisation of the patient and to facilitate the process of adaptation. Pharmacological adjuncts to promote adaptation are in the early stages of development. Primary restoration of bowel continuity, if possible, is the principle mode of surgical treatment. Surgical procedures to increase the surface area of the small intestine or improve its function may be of benefit in experienced hands, particularly in the paediatric population. Intestinal transplant is indicated at present for patients who have failed to tolerate long-term parenteral nutrition but with increasing experience, there may be a potentially expanded role for its use in the future.

Liver transplantation in the United States, 1999-2008

Changes in organ allocation policy in 2002 reduced the number of adult patients on the liver transplant waiting list, changed the characteristics of transplant recipients and increased the number of patients receiving simultaneous liver-kidney transplantation (SLK). The number of liver transplants peaked in 2006 and declined marginally in 2007 and 2008. During this period, there was an increase in donor age, the Donor Risk Index, the number of candidates receiving MELD exception scores and the number of recipients with hepatocellular carcinoma. In contrast, there was a decrease in retransplantation rates, and the number of patients receiving grafts from either a living donor or from donation after cardiac death. The proportion of patients with severe obesity, diabetes and renal insufficiency increased during this period. Despite increases in donor and recipient risk factors, there was a trend towards better 1-year graft and patient survival between 1998 and 2007. Of major concern, however, were considerable regional variations in waiting time and posttransplant survival. The current status of liver transplantation in the United States between 1999 and 2008 was analyzed using SRTR data. In addition to a general summary, we have included a more detailed analysis of liver transplantation for hepatitis C, retransplantation and SLK transplantation.

Value of FOXP3 expression in peripheral blood as rejection marker after miniature swine lung transplantation

BACKGROUND

Outcome for highly immunogenic lung transplantation remains unsatisfactory despite the development of potent immunosuppressants. The poor outcome may be the result of a lack of minimally invasive methods to detect early rejection. There is emerging clinical evidence that, paradoxically, expression of forkhead box P3 (FOXP3, a specific marker for the regulatory T cells) is upregulated within rejecting grafts.

METHODS

Orthotopic lung transplantation was performed using miniature swine without immunosuppression. Rejection was monitored by chest radiography and open lung biopsy. Expressions levels of FOXP3, perforin, Fas-L and IP-10 mRNA were quantified in the peripheral blood. In addition, rescue immunosuppressive therapy (steroid plus tacrolimus) was administered on post-operative day (POD) 4 or 6.

RESULTS

Early rejection was detected by open lung biopsy, but misdiagnosed by chest radiography on POD 4. Expression of FOXP3 in the peripheral blood reached its highest value as early as POD 4, followed by a decline. Such an increase of FOXP3 was not observed in recipients given high-dose tacrolimus. Neither perforin, Fas-L or IP-10 in the peripheral blood exhibited significant fluctuations in the early phase of rejection. Rescue immunosuppressive therapy from POD 4, when peak FOXP3 was seen, prolonged graft survival (27.2 days, versus 9.1 days without immunosuppression, p < 0.001), in contrast to POD 6, when rejection was suspected by chest radiography (11.5 days, p = not statistically significant [NS]).

CONCLUSIONS

In a miniature swine lung transplantation model, the FOXP3 mRNA level in the peripheral blood was upregulated at an early phase of rejection. The clinical implication of this finding remains to be elucidated.

The impact of MELD allocation on simultaneous liver-kidney transplantation

Model for End-Stage Liver Disease (MELD) allocation has improved the process for ranking patients on the liver transplant list. One unintended consequence has been an increase in the number of simultaneous liver-kidney (SLK) transplants. Some have argued that the system unfairly advantages patients with kidney disease and that some kidneys are being prematurely placed in SLK transplantation. This review summarizes the MELD score, assessment of kidney function in cirrhosis, the impact of kidney function in liver disease, and changes in kidney function status in liver transplant recipients in the MELD era. Finally, recommendations regarding who should receive SLK transplants are reviewed.

Reassessing selection criteria prior to liver transplantation for hepatocellular carcinoma utilizing the Scientific Registry of Transplant Recipients database

The current model of liver graft allocation in place in the United States favors transplantation of patients with small hepatocellular carcinomas (HCCs) within the Milan criteria (a single tumor up to 5 cm in diameter or up to three lesions, none larger than 3 cm). Although several reports have suggested that these criteria could be extended, there is currently no agreement on new selection tools. In this study, we performed an overview of 6478 adult recipients of an isolated first liver transplant registered in the Scientific Registry of Transplant Recipients (SRTR) database. From March 2002 to January 2008, increasing numbers of patients outside Milan criteria (P <or= 0.001) have been registered for a transplant, but they still represent less than 5% of the transplants performed for HCC. Of all the tested variables (tumor number, largest tumor size, and Milan and University of California San Francisco criteria), only total tumor volume (TTV; P <or= 0.05) and alpha fetoprotein (AFP; P <or= 0.001) could predict patient survival. While these two parameters demonstrated independent behaviors (no patient demonstrated an increase in both values), a composite score was defined, with patients with a TTV > 115 cm(3) or an AFP > 400 ng/mL being outside criteria. The combined TTV/AFP score efficiently predicted posttransplant survival (hazard ratio = 2, 95% confidence interval = 1.7-2.4, P <or= 0.001); patients not meeting these criteria had a survival below 50% at 3 years.

CONCLUSION

According to the present SRTR data, Milan criteria are too restrictive, and patients with larger TTV can enjoy satisfactory posttransplant survivals. A composite patient selection score combining TTV and AFP was the most effective of all tested staging criteria for the prediction of posttransplant patient survival for candidates with HCC.

10-year review of pediatric intestinal failure: clinical factors associated with outcome

Prediction of outcomes in pediatric intestinal failure is challenging but essential to guide intestinal rehabilitation and transplantation decisions. This review of intestinal failure patients spanning 10 years examines clinical details in relation to outcome to identify factors that may refine predictive accuracy. A search was conducted to identify all children with intestinal failure managed at Stollery Children's Hospital between January 1994 and December 2003. They were divided into 3 groups: early death occurring <or=30 days of age, parenteral nutrition dependence for 30-100 days, and parenteral nutrition dependence for >100 days. The long-term group was divided according to outcome: death or adaptation. Demographics, diagnosis, nutrition requirements, laboratory parameters, and clinical data were recorded. Groups were compared to identify factors associated with outcome. Necrotizing enterocolitis, gastroschisis, and intestinal atresias were the most common causes for intestinal failure; outcome was not related to diagnosis. Although withdrawal of therapy was common in the early death group, most babies had one or more additional significant comorbidity. Among the 29 babies requiring parenteral nutrition for >100 days with known outcomes, 12 died, 16 adapted fully, and 1 received a multivisceral transplant. Intestinal length >40 cm was associated with a significantly increased risk of mortality (P< .001). Abnormal laboratory values (bilirubin, aspartate aminotransferase, alanine aminotransferase, albumin, and platelet count) after 5 months of age were also significantly different between groups. This data, together with data from previous reviews, should be used to investigate potential predictive factors in prospective studies, particularly in the context of expert multidisciplinary care.

Calcineurin inhibitor sparing in paediatric solid organ transplantation : managing the efficacy/toxicity conundrum

Despite their efficacy, the calcineurin inhibitors (CNIs) ciclosporin and tacrolimus carry a risk of debilitating adverse effects, especially nephrotoxicity, that affect the long-term outcome and survival of children who are given organ transplants. Simple reduction in dosage of CNI has little or no long-term benefit on their adverse effects, and complete withdrawal without threatening graft outcome may only be possible after liver transplantation. Until the last decade, the only option was to increase corticosteroid and/or azathioprine doses, which imposed additional long-term hazards. Considered here are the emerging generation of new agents offering an opportunity for improving long-term graft survival, minimizing CNI-related adverse events and ensuring patient well-being.A holistic, multifaceted strategy may need to be considered - initial selection and optimized use and monitoring of immunosuppressant regimens, early recognition of indicators of patient and graft dysfunction, and, where applicable, early introduction of CNI-sparing regimens facilitating CNI withdrawal. The evidence reviewed here supports these approaches but remains far from definitive in paediatric solid organ transplantation. Because de novo immunosuppression uses CNI in more than 93% of patients, reduction of CNI-related adverse effects has focused on CNI sparing or withdrawal.A recurring theme where sirolimus and mycophenolate mofetil have been used for this purpose is the importance of their early introduction to limit CNI damage and provide long-term benefit: for example, long-term renal function critically reflects that at 1 year post-transplant. While mycophenolic acid shows advantages over sirolimus in preserving renal function because the latter is associated with proteinuria, sirolimus appears the more potent immunosuppressant but also impairs early wound healing. The use of CNI-free immunosuppressant regimens with depleting or non-depleting antibodies plus sirolimus and mycophenolic acid needs much wider investigation to achieve acceptable rejection rates and conserve renal function. The adverse effects of the alternative immunosuppressants, particularly the dyslipidaemia associated with sirolimus, needs to be minimized to avoid replacing one set of adverse effects (from CNIs) with another. While we can only conjecture that judicious combinations with the second generation of novel immunosuppressants currently in development will provide these solutions, a rationale of low-dose therapy with multiple immunosuppressants acting by complementary mechanisms seems to hold the promise for efficacy with minimal toxicity until the vision of tolerance achieves reality.

Re-weighting the model for end-stage liver disease score components

BACKGROUND & AIMS

Liver transplant candidates with mild hepatic synthetic dysfunction and marked renal insufficiency may have higher Model for End-Stage Liver Disease (MELD) scores than candidates with severe liver disease and normal renal function. We re-estimated MELD coefficients and evaluated the effect of updated MELD on the liver transplant waiting list ranking.

METHODS

Scientific Registry of Transplant Recipients data was analyzed for 38,899 adults wait-listed between September, 2001 and December, 2006. A time-dependent Cox regression waiting list mortality model estimated updated MELD component coefficients. Rank correlation between existing and updated MELD scores was computed.

RESULTS

Existing MELD component coefficient (log(e) creatinine, 0.957 vs 1.266 [95% confidence interval (CI), 1.21-1.32]; log(e) bilirubin, 0.378 vs 0.939 [95% CI, 0.91-0.97]; log(e) international normalized ratio, 1.120 vs 1.658 [95% CI, 1.58-1.74]) was significantly different than updated counterpart. Index of concordance was higher for updated MELD than existing MELD for predicting overall (0.68 vs. 0.64) and 90-day waiting list mortality (0.77 vs. 0.75). Rank correlation between existing and updated MELD scores was 0.95 for all candidates and 0.72 for candidates with existing MELD >or=20. Among candidates with equal existing MELD, those with lower creatinine and higher bilirubin had significantly higher waiting list mortality.

CONCLUSIONS

Existing MELD coefficient components are significantly different than those calculated from national waiting list data. Updated MELD assigns lower weight to creatinine and international normalized ratio and higher weight to bilirubin. Updated MELD better predicts waiting list mortality. Using updated MELD for liver allocation would alter waiting list candidate ranking.

Technical refinements in small bowel transplantation

PURPOSE OF REVIEW

This review focuses on the recently described or revised refinements or innovations in small bowel transplantation.

RECENT FINDINGS

Changes in donor selection criteria; cadaveric procurement techniques; organ preservation solutions; management of the recipient abdominal wall; technical modifications, pitfalls and recommendations to be applied during the engraftment as well as intestinal living donation will be covered.

SUMMARY

Intestinal transplantation has evolved over time to become a clinically accepted therapy for patients with intestinal failure. Short- and long-term results have improved. The surgical procedures have been standardized and the applications broaden, but there have been recently published refinements that might affect the future results of clinical intestinal transplantation and guide research.

Live donor adult liver transplantation

PURPOSE OF REVIEW

Because the gap between liver organ supply and demand continues to increase, adult living-donor liver transplantation continues to represent a significant pool of organs.

RECENT FINDINGS

With this in mind, we discuss recent issues in adult living-donor liver transplantation, including issues with donor evaluation and selection, donor liver biopsy, orphan organ allocation, donor morbidity and mortality, outcomes compared with deceased donor liver transplant from time of evaluation, death on the waiting list, and evolving recipient indications for living-donor liver transplantation.

SUMMARY

Increasing the number of living-donor liver transplants would allow us to expedite transplant, avoid death on the waitlist, and possibly save more lives by expanding the criteria for transplant. These benefits must always be weighed against the potential risks and complications to the donor, which can be significant.

Donor postextubation hypotension and age correlate with outcome after donation after cardiac death transplantation

BACKGROUND

Compared with standard donors, kidneys recovered from donors after cardiac death (DCD) exhibit higher rates of delayed graft function (DGF), and DCD livers demonstrate higher rates of biliary ischemia, graft loss, and worse patient survival. Current practice limits the use of these organs based on time from donor extubation to asystole, but data to support this is incomplete. We hypothesized that donor postextubation parameters, including duration and severity of hemodynamic instability or hypoxia might be a better predictor of subsequent graft function.

METHODS

We performed a retrospective examination of the New England Organ Bank DCD database, concentrating on donor factors including vital signs after withdrawal of support.

RESULTS

Prolonged, severe hypotension in the postextubation period was a better predictor of subsequent organ function that time from extubation to asystole. For DCD kidneys, this manifested as a trend toward increased DGF. For DCD livers, this manifested as increased rates of poor outcomes. Maximizing the predictive value of this test in the liver cohort suggested that greater than 15 min between the time when the donor systolic blood pressure drops below 50 mm Hg and flush correlates with increased rates of diffuse biliary ischemia, graft loss, or death. Donor age also correlated with worse outcome.

CONCLUSIONS

Time between profound instability and cold perfusion is a better predictor of outcome than time from extubation to asystole. If validated, this information could be used to predict DGF after DCD renal transplant and improve outcomes after DCD liver transplant.

Live donors in liver transplantation

Living donor liver transplantation (LDLT) has been controversial since its inception. Begun in response to deceased donor organ shortage and waiting list mortality, LDLT was initiated in 1989 in children, grew rapidly after its first general application in adults in the United States in 1998, and has declined since 2001. There are significant risks to the living donor, including the risk of death and substantial morbidity, and 2 highly publicized donor deaths are thought to have contributed to decreased enthusiasm for LDLT. Significant improvements in outcomes have been seen over recent years, and data, including from the National Institutes of Health-funded Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL), have established a survival benefit from pursuing LDLT. Despite this, LDLT still composes less than 5% of adult liver transplants, significantly less than in kidney transplantation where living donors compose approximately 40% of all transplantations performed. The ethics, optimal utility, and application of LDLT remain to be defined. In addition, most studies to date have focused on posttransplantation outcomes and have not included the effect of the learning curve on outcome or the potential impact of LDLT on waiting list mortality. Further growth of LDLT will depend on defining the optimal recipient and donor characteristics for this procedure as well as broader acceptance and experience in the public and in transplant centers.