Evaluation of acute renal failure in the liver transplantation perioperative period: incidence and impact

Low preoperative serum uric acid is associated with early acute kidney injury after living donor liver transplantation

BACKGROUND

Liver transplantation is treatment option for patients with end-stage liver disease and hepatocellular carcinoma. Renal function deterioration significantly impacts the survival rates of liver recipients, and serum uric acid (SUA) is associated with both acute and chronic renal function disorders. Thus, our study aimed to assess the relationship and predictive value of preoperative SUA level and postoperative acute kidney injury (AKI) in living donor liver transplantation (LDLT).

METHODS

We conducted a prospective observational study on 87 patients undergoing LDLT. Blood samples were collected immediately before LDLT, and renal function status was followed up for 3 consecutive days postoperatively.

RESULTS

Low SUA levels (cutoff value 4.15 mg/dL) were associated with a high risk of early posttransplantation AKI. The area under the curve was 0.73 (sensitivity, 79.2%; specificity, 59.4%). Although not statistically significant, there were no deaths in the non-AKI group but two in the early AKI group secondary to liver graft dysfunction in addition to early AKI within the first month after LDLT.

CONCLUSION

AKI after liver transplantation may lead to a deterioration of patient status and increased mortality rates. We determined low preoperative SUA levels as a possible risk factor for early postoperative AKI.

Tacrolimus 4-hour monitoring in liver transplant patients is non-inferior to trough monitoring: The randomized controlled FK04 trial

BACKGROUND

After liver transplantation (LT), tacrolimus and ciclosporin treatment can lead to, partially concentration-dependent, chronic kidney disease. Monitoring ciclosporin with two-hour levels reduced overexposure and led to better renal function than trough-monitoring (C0). For tacrolimus, a 4-hour level (C4) can give a reasonable approximation of total drug exposure. We evaluated whether monitoring tacrolimus in stable patients after LT by C4 was superior to C0 regarding renal function, rejection and metabolic parameters.

METHODS

This open label randomized controlled trial compared C4 monitoring of tacrolimus BID (Prograft) to trough (C0) monitoring in stable LT recipients. The target range for C4 of 7.8-16 ng/ml was calculated to be comparable with target C0 of 4-8 ng/ml. Primary endpoint was the effect on renal function and secondary endpoints were the occurrence of treated biopsy-proven acute rejection, blood pressure and metabolic parameters, during 3 months of follow-up.

RESULTS

Fifty patients were randomized to C0 (n = 25) or C4 (n = 25) monitoring. There was no difference in renal function between the C0 and the C4 group (p = .98 and p = .13 for CG and MDRD at 3 months). Also, the amount of proteinuria was similar (p = .59). None of the patients suffered from graft loss or was treated for rejection. Metabolic parameters did not differ between the two groups.

CONCLUSION

Tacrolimus 4-hour monitoring in stable LT patients is not superior to trough monitoring, regarding the effect on renal function, but is safe for use to facilitate tacrolimus monitoring in an afternoon outpatient clinic.

[Kidney failure after liver transplantation]

One third of cirrhotic patients present impaired kidney function. It has multifactorial causes and has a harmful effect on patients' morbi-mortality before and after liver transplant. Kidney function does not improve in all patients after liver transplantation and liver-transplant recipients are at high risk of developing chronic kidney disease. Causes for renal dysfunction can be divided in three groups: preoperative, peroperative and postoperative factors. To date, there is no consensus for the modality of evaluation the risk for chronic kidney disease after liver transplantation, and for its prevention. In the present review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease to determine a risk stratification for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this setting, and highlight the indications of combined liver-kidney transplantation.

Kidney Failure after Liver Transplantation

One-third of patients with cirrhosis present kidney failure (AKI and CKD). It has multifactorial causes and a harmful effect on morbidity and mortality before and after liver transplantation. Kidney function does not improve in all patients after liver transplantation, and liver transplant recipients are at a high risk of developing chronic kidney disease. The causes of renal dysfunction can be divided into three groups: pre-operative, perioperative and post-operative factors. To date, there is no consensus on the modality to evaluate the risk of chronic kidney disease after liver transplantation, or for its prevention. In this narrative review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease in order to establish a risk categorization for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this context, and highlight the indications of combined liver–kidney transplantation.

Long-Term Outcomes of Liver Transplantation in Patients With Pretransplant Renal Dysfunction Treated With Induction Therapy and Delayed Reduced De Novo Once-Daily Tacrolimus

BACKGROUND AND AIM

Renal dysfunction is related to short- and long-term survival after liver transplantation. We present herein a retrospective analysis of our experience with liver transplantation in recipients with pretransplant renal dysfunction treated with induction therapy followed by delayed/reduced de novo once-daily tacrolimus.

METHODS

Liver transplantations performed between April 2008 and August 2011 were included in this study. Pretransplant renal dysfunction was defined as estimated glomerular filtration rate <60 mL/min. Interleukin-2 receptor antagonists were used for induction therapy. Initial once-daily tacrolimus dose was 0.10 mg/kg/day or 0.07 mg/kg/day if combined with mycophenolate mofetil (MMF). Tacrolimus target trough levels were 4 to 6 ng/mL during the first post-transplant year and <4 ng/mL the rest of the follow-up.

RESULTS

Nineteen patients comprised the study cohort with a median follow-up of 56.4 months (range, 11-78). Median day of tacrolimus introduction was 7 (range, 3-12). Once-daily tacrolimus was withdrawn in 6 patients (31.6%) due to evolution of renal dysfunction in all cases. At 5 years, 30% of the patients were under MMF monotherapy. Mean tacrolimus trough levels were maintained under 5 ng/mL. Mean estimated glomerular filtration rate at 5 years was 55.3 ± 12.7 mL/min. No patient needed hemodialysis or renal transplantation over the follow-up. Patient survival at 5 years was 78.9%.

CONCLUSIONS

Induction therapy followed by delayed/reduced de novo once-daily tacrolimus and maintenance of low tacrolimus exposition during the follow-up is effective to maintain long-term renal function and to achieve favorable patient survival in liver transplant recipients with pretransplant renal dysfunction.

Risk factors and associated outcomes of early acute kidney injury in pediatric liver transplant recipients: A retrospective study

BACKGROUND

Acute kidney injury (AKI) may contribute to high mortality rates after liver transplantation. Few studies have investigated AKI in pediatric liver transplantation. This retrospective study was conducted to investigate the risk factors for and associated outcomes of AKI in pediatric liver transplant recipients.

METHODS

Eighty pediatric liver transplant patients were included. The occurrence of AKI was defined by the KDIGO Clinical Practice Guidelines for Acute Kidney Injury. A multivariate regression analysis model was used to investigate risk factors for AKI in the pediatric liver recipients.

RESULTS

The final multivariable regression model showed that biliary atresia (odds ratio [OR] = 0.097, p = 0.03), increased time of the anhepatic phase (OR = 0.871, p = 0.005) and lower postoperative jaundice clearance (OR = 13.936, p = 0.02) were independently associated with the development of AKI in pediatric patients. Additionally, cumulative 3-year patient (p = 0.15) and graft (p = 0.26) survival rates between the non-acute kidney injury (NAKI) and AKI groups were 95.2% vs 86.8% and 90.5% vs 84.2%, respectively.

CONCLUSION

Pediatric liver transplant recipients with a presence of biliary atresia, increased time of anhepatic phase, and a lower postoperative jaundice clearance had an increased risk of AKI. The long-term outcomes of patients who developed AKI appears to be worse compared with those having NAKI.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level III.

Repeat liver resection versus salvage liver transplant for recurrent hepatocellular carcinoma: A propensity score-adjusted and -matched comparison analysis

BACKGROUNDS/AIMS

Repeat liver resection (RLR) and salvage liver transplantation (SLT) are viable treatment options for recurrent hepatocellular carcinoma (HCC). With possibly superior survival outcomes than RLR, SLT is however, limited by liver graft availability and poses increased perioperative morbidity. In this study, we seek to compare the outcomes of RLR and SLT for patients with recurrent HCC.

METHODS

Between 1999 and 2018, 94 and 16 consecutive patients who underwent RLR and SLT respectively were identified. Further retrospective subgroup analysis was conducted, comparing 16 RLR with 16 SLT patients via propensity-score matching.

RESULTS

After propensity-score adjusted analyses, SLT demonstrated inferior short-term perioperative outcomes than RLR, with increased major morbidity (57.8% vs 5.4 %, p=0.0001), reoperations (39.1% vs 0, p<0.0001), renal insufficiency (30.1% vs 3%, p=0.0071), bleeding (19.8% vs 2.2%, p=0.0289), prolonged intensive care unit stay (median=4 vs 0 days, p<0.0001) and hospital stay (median=19.8 vs 7.1days, p<0.001). However, SLT showed significantly lower recurrence rate (15.4% versus 70.3%, p=0.0005) and 5-year cumulative incidence of recurrences (19.4% versus 68.4%, p=0.005). Propensity-matched subgroup analysis showed concordant findings.

CONCLUSIONS

While SLT offers potentially reduced risks of recurrence and trended towards improved long-term survival outcomes relative to RLR, it has poorer short-term perioperative outcomes. Patient selection is prudent amidst organ shortages to maximise allocated resources and optimise patient outcomes.

Urinary Neutrophil Gelatinase Associated Lipocalins (NGALs) predict acute kidney injury post liver transplant

BACKGROUND

Acute Kidney Injury, a common complication of liver transplant, is associated with a significant increase in the risk of morbidity, mortality and graft loss. Current diagnostic criteria leaves a delay in diagnosis allowing further potential irreversible damage. Early biomarkers of renal injury are of clinical importance and Neutrophil Gelatinase Associated Lipocalins (NGALs) and Syndecan-1 were investigated.

METHODS

AKI was defined according to the Acute Kidney Injury Network criteria. Urine and blood samples were collected pre-operatively, immediately post-op and 24 h post reperfusion to allow measurement of NGAL and Syndecan-1 levels.

RESULTS

13 of 27 patients developed an AKI. Patients who developed AKI had significantly higher peak transaminases. Urinary NGAL, plasma NGAL and Syndecan-1 levels were significantly elevated in all patients post reperfusion. Urinary NGAL levels immediately post-op were significantly higher in patients who developed an AKI than those that didn't [1319 ng/ml vs 46.56 ng/ml, p ≤ 0.001]. ROC curves were performed and urinary NGAL levels immediately post-op were an excellent biomarker for AKI with an area under the curve of 0.948 (0.847-1.00).

CONCLUSIONS

Urinary NGAL levels measured immediately post-op accurately predict the development of AKI and their incorporation into clinical practise could allow early protocols to be developed to treat post transplant AKI.

Neutrophil Gelatinase-Associated Lipocalin (NGAL) in predicting acute kidney injury following orthotopic liver transplantation: A systematic review

BACKGROUND

Acute kidney injury (AKI) is common after orthotopic liver transplantation (OLT) usually occurring early post-transplant. Multiple causes include graft preservation injury, blood loss, hypotension but also severity of recipient liver disease. Early intervention in AKI has both short and long term patient benefits. Unfortunately there are no current clinical biomarkers of early AKI.

AIM

To assess the value of NGAL in predicting AKI following OLT.

METHODS

Ovid MEDLINE and EMBASE were searched between the years of 2000 and 2017 for studies using keywords: Neutrophil Gelatinase Associated Lipocalin or NGAL variants combined with synonyms for liver transplantation.

RESULTS

96 studies were identified. 11 studies including 563 patients were considered suitable for analysis. Both urinary (uNGAL) and plasma NGAL (pNGAL) measurement were found to predict AKI after liver transplantation. Optimal reported area under the receiver-operator characteristics curve (AUROC) values of 0.5-0.83 and 0.54-0.86 respectively.

CONCLUSIONS

NGAL is a good predictor of early AKI post OLT although there is considerable variation in the published results. Further studies with prospectively defined cut-off values, standardized definitions of AKI and rigorous data reporting should be conducted to establish its clinical usefulness and limitations.

Safety and Efficacy of Early Everolimus When Calcineurin Inhibitors Are Not Recommended in Orthotopic Liver Transplantation

Our aim was to study the safety and efficacy of immunosuppression with everolimus (EVL) within the 1st month after orthotopic liver transplantation (LT) when calcineurin inhibitors are not recommended. For this purpose, 28 recipients who had been treated with EVL within the 1st month after adult LT were eligible to enter in a retrospective multicenter study. Patients were followed up for 12 months after LT. EVL therapy was initiated at a median of 14 days (range, 4-24) after LT. The reason for early EVL was neurotoxicity in 14 cases, renal dysfunction in 12, and acute cellular rejection combined with renal impairment in 2. In 23 patients, immunosuppression was EVL + mycophenolate mofetil/mycophenolate sodium + steroids, and EVL + tacrolimus + steroids/mycophenolate sodium was used in 4 cases. Neurotoxicity disappeared in all patients. Renal function in patients with renal impairment improved from a median of 32 mL/min/1.73 m² at the moment of implementation of EVL to 62 mL/min/1.73 m² at 1 year. Four patients (14.3%) developed acute cellular rejection. We observed incisional hernia in 4 patients (14.3%), hematologic complications in 6 (21.4%), proteinuria in 2 (7.1%), edema and/or effusions in 8 (28.6%), and dyslipidemia in 12 (42.8%). No arterial complications were observed. EVL was withdrawn in 5 patients during the 1st year after LT. One-year patient survival was 92.7%. In conclusion, use of EVL within the 1st month after LT when calcineurin inhibitors are not recommended seems to be an effective therapeutic option with an acceptable safety profile.

Acute kidney injury following liver transplantation: a systematic review of published predictive models

Acute kidney injury is a frequent postoperative complication amongst liver transplant recipients and is associated with increased morbidity and mortality. This systematic review analysed the existing predictive models, in order to solidify current understanding. Articles were selected for inclusion if they described the primary development of a clinical prediction model (either an algorithm or risk score) to predict AKI post liver transplantation. The database search yielded a total of seven studies describing the primary development of a prediction model or risk score for the development of AKI following liver transplantation. The models span thirteen years of clinical research and highlight a gradual change in the definitions of AKI, emphasising the need to employ standardised definitions for subsequent studies. Collectively, the models identify a diverse range of predictive factors with several common trends. They emphasise the impact of preoperative renal dysfunction, liver disease severity and aetiology, metabolic risk factors as well as intraoperative variables including measures of haemodynamic instability and graft quality. Although several of the models address postoperative parameters, their utility in predictive modelling seems to be of questionable relevance. The common risk factors identified within this systematic review provide a minimum list of variables, which future studies should address. Research in this area would benefit from prospective, multi-site studies with larger cohorts as well as the subsequent internal and external validation of predictive models. Ultimately, the ability to identify patients at high risk of post-transplant AKI may enable early intervention and perhaps prevention.

Incidence and risk factors for early renal dysfunction after liver transplantation

AIM: To determine renal dysfunction post liver transplantation, its incidence and risk factors in patients from a Belgian University Hospital.

METHODS: Orthotopic liver transplantations performed from January 2006 until September 2012 were retrospectively reviewed (n = 187). Patients with no renal replacement therapy (RRT) before transplantation were classified into four groups according to their highest creatinine plasma level during the first postoperative week. The first group had a peak creatinine level below 12 mg/L, the second group between 12 and 20 mg/L, the third group between 20 and 35 mg/L, and the fourth above 35 mg/L. In addition, patients who needed RRT during the first week after transplantation were also classified into the fourth group. Perioperative parameters were recorded as risk factors, namely age, sex, body mass index (BMI), length of preoperative hospital stay, prior bacterial infection within one month, preoperative ascites, preoperative treatment with β-blocker, angiotensin-converting enzyme inhibitor or non steroidal anti-inflammatory drugs, preoperative creatinine and bilirubin levels, donor status (cardiac death or brain death), postoperative lactate level, need for intraoperative vasopressive drugs, surgical revision, mechanical ventilation for more than 24 h, postoperative bilirubin and transaminase peak levels, postoperative hemoglobin level, amount of perioperative blood transfusions and type of immunosuppression. Univariate and multivariate analysis were performed using logistic ordinal regression method. Post hoc analysis of the hemostatic agent used was also done.

RESULTS: There were 78 patients in group 1 (41.7%), 46 in group 2 (24.6%), 38 in group 3 (20.3%) and 25 in group 4 (13.4%). Twenty patients required RRT: 13 (7%) during the first week after transplantation. Using univariate analysis, the severity of renal dysfunction was correlated with presence of ascites and prior bacterial infection, preoperative bilirubin, urea and creatinine level, need for surgical revision, use of vasopressor, postoperative mechanical ventilation, postoperative bilirubin and urea, aspartate aminotransferase (ASAT), and hemoglobin levels and the need for transfusion. The multivariate analysis showed that BMI (OR = 1.1, P = 0.004), preoperative creatinine level (OR = 11.1, P < 0.0001), use of vasopressor (OR = 3.31, P = 0.0002), maximal postoperative bilirubin level (OR = 1.44, P = 0.044) and minimal postoperative hemoglobin level (OR = 0.059, P = 0.0005) were independent predictors of early post-liver transplantation renal dysfunction. Neither donor status nor ASAT levels had significant impact on early postoperative renal dysfunction in multivariate analysis. Absence of renal dysfunction (group 1) was also predicted by the intraoperative hemostatic agent used, independently of the extent of bleeding and of the preoperative creatinine level.

CONCLUSION: More than half of receivers experienced some degree of early renal dysfunction after liver transplantation. Main predictors were preoperative renal dysfunction, postoperative anemia and vasopressor requirement.

Does the development of chronic kidney disease and acute kidney injury affect the prognosis after living donor liver transplantation?

BACKGROUND AND AIMS

Chronic kidney disease (CKD) and acute kidney injury (AKI) have been discussed as complications following living donor liver transplantation (LDLT). The aim of this study was to clarify the relationships among CKD, AKI, and the prognosis after LDLT.

METHODS

This study included 118 patients who underwent LDLT in our department. A low eGFR (<60 mL/min/1.73 m(2) ) was regarded to indicate CKD. AKI 1 and AKI 2 were characterized by an increase in the serum creatinine level of 0.5 and 1.0 mg/dL, respectively, within one wk after LDLT. We investigated the risk factors for and the relevance of CKD and AKI on the prognosis.

RESULTS

AKI 1 was associated with sepsis and intra-operative bleeding (p = 0.0032, p = 0.001). AKI 2 was associated with sepsis and hepatitis C infection (p < 0.001, p = 0.027). A pre-operative eGFR of 60-89 and diabetes were the risk factors for the development of CKD in POY 2 (p = 0.018, p = 0.002). AKI 2, sepsis, and diabetes were the risk factors for the patient death within one yr after LDLT (p = 0.010, p = 0.002, p = 0.022). AKI 2 and sepsis were the risk factors for death within two yr after LDLT (p = 0.005, p = 0.018).

CONCLUSIONS

Recognizing the risk factors and careful management for preventing both AKI and CKD may improve the prognosis of patients following LDLT.

Evaluation of renal functions in pediatric liver transplantation

AKI is an important complication after LT. As our LT series contains a quite high number of children with ALF unlike published studies, we aimed to determine pre-LT and long-term renal functions in children both with ALF and with CLD. Demographic and disease-related data of 134 transplanted children were evaluated retrospectively. Pre-LT and follow-up GFR and pediatric RIFLE scores were determined. Mean pre-LT GFR was not dependent on the disease presentation or severity of chronic disease. While there was an initial decline until first week of post-LT in CLD children, an increase was observed in ALF. Neither mean GFR nor the pRIFLE on follow-up was different with respect to the type of LT or disease presentation. Mean GFR at first and sixth months were lower in children on cyclosporine compared to tacrolimus (p = 0.001 and p = 0.002, respectively). In conclusion, GFR-time curve was different in children with or without ALF. Type of LT, and severity of the CLD were not risk factors for CKD in any time, but younger age at LT, CLD, and cyclosporine usage were at sixth months of follow-up.

Incidence and Outcomes of Acute Renal Failure Following Liver Transplantation: A Population-Based Cohort Study

The aim of our large, population-based, cohort study was to explore the risk factors of acute renal failure (ARF) after liver transplant (LT) in Taiwan.From the Taiwanese National Health Insurance Research Database, 2862 patients who had undergone LT without pretransplant dialysis between July 1, 1998, and December 31, 2012, were identified. Preoperative, operative, and perioperative risks factors were considered and analyzed using logistic regression analysis, after adjusting for age and sex. All patients were followed up until the study endpoint or death.The final dataset included 214 patients with ARF and 2648 without ARF post-LT. Preoperative cerebrovascular diseases were the most important identifiable risk factor for ARF post-LT. Comparison of outcomes for patients "with" and "without" ARF indicated higher incidence rates of bacteremia, pneumonia, and postoperative bleeding, as well as longer stays in both intensive care unit and hospital. Kaplan-Meier mortality curves identified higher rates of mortality for patients' developing ARF at 1-year post-LT and overall at 14.5 years postsurgery.We provide evidence of a high incidence of ARF post-LT in Taiwan, with documented association of ARF with higher incidence rates of morbidity and mortality in this clinical population. The most important identifiable risk factor for ARF in our study was cerebrovascular diseases.

Comparison of RIFLE and AKIN criteria in the evaluation of the frequency of acute kidney injury in post-liver transplantation patients

BACKGROUND

Acute renal dysfunction is presented quite often after orthotopic liver transplantation (LT), with a reported incidence of 12-64%. The "RIFLE" criteria were introduced in 2004 for the definition of acute kidney injury (AKI) in critically ill patients, and a revised definition was proposed in 2007 by the Acute Kidney Injury Network (AKIN), introducing the AKIN criteria. The aim of this study was to record the incidence of AKI in patients after LT by both classifications and to evaluate their prognostic value on mortality.

METHODS

We retrospectively evaluated the records of patients with LT over 2 years (2011-2012) and recorded the incidence of AKI as defined by the RIFLE and AKIN criteria. Preoperative and admission severity of disease scores, duration of mechanical ventilation, intensive care unit length of stay, and 30- and 180-day survivals were also recorded.

RESULTS

Seventy-one patients were included, with an average age of 51.78 ± 10.3 years. The incidence of AKI according to the RIFLE criteria was 39.43% (Risk, 12.7%; Injury, 12.7%; Failure, 14.1%), whereas according to the AKIN criteria it was 52.1% (stage I, 22.5%; stage II, 7%; stage II 22.55%). AKI, regardless of the classification used, was related to the Model for End-Stage Liver Disease score, the volume of transfusions, the duration of mechanical ventilation, and survival. The presence of AKI was related to higher mortality, which rose proportionally with the severity of AKI as defined by the stages of either the RIFLE or the AKIN criteria.

CONCLUSIONS

AKI classifications according to the RIFLE and AKIN criteria are useful tools in the recognition and classification of the severity of renal dysfunction in patients after LT, because they are associated with higher mortality, which rises proportionally with the severity of renal disease.

The use of renal replacement therapy in critically ill pediatric small bowel transplantation candidates and recipients: Experience from one center

Outcomes for pediatric SBT patients requiring perioperative RRT in the PICU remain unknown. The objectives were to document our center's experience with PICU SBT patients receiving perioperative RRT and to identify variables predictive of survival to discharge. A retrospective chart review of patients (ages, 0-18 yr) between January 1, 2000 and December 31, 2011 that received RRT within a SBT perioperative period and were transplanted at our university-affiliated, tertiary care children's hospital was performed. Six SBT patients received perioperative RRT (ages, 5-12 yr). Three patients (50%) survived to hospital discharge. Among survivors, RRT was required for a total of 1-112 days (mean, 49.7 days). All three survivors survived to hospital discharge without renal transplantation and free of RRT. There was a trend toward increased survival among older patients receiving RRT (p = 0.05). Survivors had a higher I-125 GFR prior to PICU admission (p = 0.045). A higher I-125 GFR prior to PICU admission among survivors may support this test's utility during SBT evaluation. In our experience, a high survival rate and freedom from RRT at the time of discharge support RRT use in the SBT population.

Acute kidney injury following orthotopic liver transplantation: incidence, risk factors, and effects on patient and graft outcomes

BACKGROUND

Liver transplant recipients frequently develop acute kidney injury (AKI), but the predisposing factors and long-term consequences of AKI are not well understood. The aims of this study were to identify predisposing factors for early post-transplant AKI and the impact of AKI on patient and graft survival and to construct a model to predict AKI using clinical variables.

METHODS

In this 5-year retrospective study, we analysed clinical and laboratory data from 424 liver transplant recipients from our centre.

RESULTS

By 72 h post-transplant, 221 patients (52%) had developed AKI [according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria]. Predisposing factors for development of AKI were female sex, weight (>100 kg), severity of liver disease (Child-Pugh score), pre-existing diabetes mellitus, number of units of blood or fresh frozen plasma transfused during surgery, and non-alcoholic steatohepatitis as the aetiology of end-stage liver disease (P≤0.05). Notably, preoperative serum creatinine (SCr) was not a significant predisposing factor. After fitting a forward stepwise regression model, female sex, weight >100 kg, high Child-Pugh score, and diabetes remained significantly associated with the development of AKI within 72 h (P≤0.05). The area under the receiver operator characteristic curve for the final model was 0.71. The incidence of new chronic kidney disease and requirement for dialysis at 3 months and 1 yr post-transplant were significantly higher among patients who developed AKI.

CONCLUSIONS

Development of AKI within the first 72 h after transplant impacted short-term and long-term graft survival.

Renal function status in liver transplant patients in the first month post-transplant is associated with progressive chronic kidney disease

AIM

Renal dysfunction is a common complication of liver transplantation (LT), related to hepatorenal syndrome with end-stage liver disease or calcineurin-inhibitor nephrotoxicity. Chronic kidney disease (CKD) is also a common problem in long-term survivors post-LT. This study was done to investigate the association between renal functional status soon after LT and the development of CKD.

METHODS

We retrospectively evaluated 63 patients who were aged 18 years or older, and underwent LT at Tohoku University Hospital. The estimated glomerular filtration rate (eGFR) was calculated by the Modification of Diet in Renal Disease study equation for Japan.

RESULTS

Before transplantation, 25 patients (39.7%) were diagnosed with CKD (eGFR, <60 mL/min per 1.73 m(2) ). The incidence of CKD was 22.4% (13/58) at 2 years, 23.2% (13/56) at 3 years and 22.7% (12/54) at 5 years. The patients with CKD at 2 years post-transplant were more likely to have a history of glomerulonephritis, and were significantly older at the time of LT, compared to those without CKD. Levels of eGFR of less than 60 mL/min per 1.73 m(2) in the first month post-transplant and a volume of intraoperative blood loss of more than 300 mL/kg were predictive factors for the development of CKD at 2 years post-transplant and thereafter.

CONCLUSION

We have shown that there is an improvement of renal function in the majority of patients after LT. Regardless of the presence of pre-existing CKD, both renal function status at the first month post-transplant and a volume of intraoperative blood loss were predictive factors for the development of CKD at 2 years post-transplant and thereafter.

A meta-analysis of complications following deceased donor liver transplant

BACKGROUND

Liver transplantation is a complex surgery associated with high rates of postoperative complications. While national outcomes data are available, national rates of most complications are unknown.

DATA SOURCES

A systematic review of the literature reporting rates of postoperative complications between 2002 and 2012 was performed. A cohort of 29,227 deceased donor liver transplant recipients from 74 studies was used to calculate pooled incidences for 17 major postoperative complications.

CONCLUSIONS

This is the first comprehensive review of postoperative complications after liver transplantation and can serve as a guide for transplant and nontransplant clinicians. Efforts to collect national data on complications, such as through the National Surgical Quality Improvement Program, would improve the ability to provide patients with informed consent, serve as a tool for individual center performance monitoring, and provide a central source against which to measure interventions aimed at improving patient care.

Neutrophil gelatinase-associated lipocalin associated with irreversibility of pre-liver transplant kidney dysfunction

Kidney outcomes in early post-liver transplantation (LT) are crucial for long-term prognosis, but difficult to predict. Among 203 adult LT patients, we studied the value of plasma neutrophil gelatinase-associated lipocalin (NGAL) measured pre-LT for predicting acute kidney injury (AKI), kidney-replacement therapy within three months, and kidney dysfunction at three months post-LT. Glomerular filtration rate (GFR) was estimated by creatinine-based and cystatin C-based equations. Highest NGAL levels were among patients on pre-LT kidney-replacement therapy, whereas NGAL exceeded 200 μg/L in only three (2%) patients with pre-LT GFR >60 mL/min. Pre-LT NGAL >260 μg/L predicted GFR <60 mL/min at three months post-LT (OR 17.8, 95% CI 2.1-153) independently of 19 other variables reflecting recipient characteristics, liver and kidney function, perioperative hemodynamic stress, and immunosuppression. Of 81 patients with pre-LT GFR <60 mL/min, 48% had GFR <60 mL/min at three months, and an NGAL level >260 μg/L predicted this outcome with 90% specificity and 46% sensitivity. NGAL failed to predict post-LT AKI or need for temporary kidney-replacement therapy. In conclusion, NGAL independently predicted irreversibility of pre-LT kidney dysfunction and could thus help in optimizing patient care and in the decision to perform combined liver-kidney transplantation. Pre-LT NGAL was not useful in patients with preserved pre-LT kidney function or in predicting post-LT AKI.

Negative prognostic impact of renal replacement therapy in adult living-donor liver transplant recipients: preoperative recipient condition and donor factors

BACKGROUND

In deceased-donor liver transplantation settings, post-transplantation acute renal failure with the induction of renal replacement therapy (RRT) is known to have negative effects on graft and patient survivals. However, the impact of RRT in living-donor liver transplantation (LDLT) has not been well investigated. The aim of this study was to elucidate risk factors requiring RRT and prognostic factors after its induction.

METHODS

Clinical data on the consecutive 113 adult patients who underwent LDLT from March 2002 to May 2013 were retrospectively reviewed. They were divided into 2 groups: RRT (n = 33) and Non-RRT (n = 80). The primary reasons for receiving RRT were hepatorenal syndrome (n = 17), sepsis (n = 12), and renal hypoperfusion (n = 4).

RESULTS

Although there were no significant differences in age or sex, the Model for End-Stage Liver Disease (MELD) score was significantly higher in the RRT group than in the Non-RRT group (23 ± 13 vs 16 ± 7; P = .002). The graft-recipient weight ratio (GRWR) was significantly lower in the RRT group (0.86 ± 0.3 vs 0.99 ± 0.2; P = .025). The 1- and 5-year patient survival rates were significantly higher in the Non-RRT group than in the RRT group (respectively, 91.3% and 84.3% vs 42.9% and 25.5%; P < .001). In multivariate analysis, independent risk factors for receiving RRT were MELD score >20 (P = .044) and GRWR <0.7 (P = .039). In the RRT group, donor age >50 years (P = .042) and preoperative serum creatinine level >1.5 mg/dL (P = .049) were significant prognostic risk factors.

CONCLUSIONS

In adult LDLT patients, the induction of RRT after LDLT was a negative predictor of survival. In addition to the preoperative recipient's condition, donor factors including graft size and donor age influenced prognosis after the induction of RRT.

Risk factors for acute renal injury in living donor liver transplantation: evaluation of the RIFLE criteria

Acute renal injury (ARI) is a serious complication after liver transplantation. This study investigated the usefulness of the RIFLE criteria in living donor liver transplantation (LDLT) and the prognostic impact of ARI after LDLT. We analyzed 200 consecutive adult LDLT patients, categorized as risk (R), injury (I), or failure (F), according to the RIFLE criteria. ARI occurred in 60.5% of patients: R-class, 23.5%; I-class, 21%; and F-class, 16%. Four patients in Group-A (normal renal function and R-class) and 26 patients in Group-B (severe ARI: I- and F-class) required renal replacement therapy (P < 0.001). Mild ARI did not affect postoperative prognosis regarding hospital mortality rate in Group A (3.2%), which was superior to that in Group B (15.8%; P = 0.0015). Fourteen patients in Group B developed chronic kidney disease (KDIGO stage 3/4). The 1-, 5- and 10-year survival rates were 96.7%, 90.6%, and 88.1% for Group A and 71.1%, 65.9%, and 59.3% for Group B, respectively (P < 0.0001). Multivariate analysis revealed risk factors for severe ARI as MELD ≥ 20 [odds ratio (OR) 2.9], small-for-size graft (GW/RBW <0.7%; OR 3.1), blood loss/body weight >55 ml/kg (OR 3.7), overexposure to calcineurin inhibitor (OR 2.5), and preoperative diabetes mellitus (OR 3.2). The RIFLE criteria offer a useful predictive tool after LDLT. Severe ARI, defined beyond class-I, could have negative prognostic impact in the acute and late postoperative phases. Perioperative treatment strategies should be designed and balanced based on the risk factors for the further improvement of transplant prognosis.

Acute renal failure in liver transplant patients: Indian study

The acute renal failure is the frequent medical complication observed in liver transplant patients. The objective of this study was to determine the cause of acute renal failure in post liver transplant patients. A total of 70 patients who underwent (cadaveric 52, live 18) liver transplantation were categorized based on clinical presentation into two groups, namely hepatorenal failure (HRF, n = 29), and Hepatic failure (HF, n = 41). All the patients after the liver transplant had received tacrolimus, mycophenolate and steroids. We analyzed the modification of diet in renal disease, (MDRD) serum urea, creatinine and albumin before and after 5th and 30th day of liver transplant and data was categorized into survivors and non-survivors group. In HRF survivor group, serum creatinine, and urea levels were high and, albumin, MDRD were low in pre- transplant and reached to normal levels on 30th day of post transplant, and 79.3 % of patients in this group showed resumption of normal kidney function. On the contrary in HRF nonsurvivor group, we did not observed any significant difference and 20.7 % of patients showed irreversible changes after the liver transplant. In HF survivor group, 82.9 % of liver failure patients did not show any deviation in serum creatinine, urea, albumin and MDRD, whereas in HF non survivor group, 17.1 % of liver failure patients who had HCV positive before the transplant developed acute renal failure. The levels of creatinine, urea, albumin and MDRD were normal before the transplant and on day 30th, the levels of albumin and MDRD were significantly low whereas serum urea, creatinine levels were high. In conclusion, based on these observations, an diagnosis and treatment of Acute renal failure is important among the liver transplantation cases in the early postoperative period.

A single-center analysis to evaluate kidney function parameters after liver transplantation in adult patients

Severe renal dysfunction may occur after orthotopic liver transplantation (OLT). In this study, we retrospectively analyzed a single-center series of adult liver recipients (n = 62) seeking to identify patients prone to develop renal dysfunction during follow-up. Liver recipients (age range, 53.54 ± 8.19 years; female/male: 21/41) who underwent a first OLT from a brain dead donor were enrolled according to strict criteria. We enrolled only liver recipients with 5 serum creatinine (SCr) measurements after hospital discharge and at least 1 measurement/year with a follow-up period of not less than 2 years. We estimated glomerular filtration rate (eGFR) using the formula developed by the Mayo Clinic. The average rate of SCr change after OLT was 0.0065 ± 0.013 mg/dL/mo. By calculating the per-patient slope, the average rate of SCr change was 0.000165 ± 0.000383 mg/dL (0.000007 ± 0.000017 mg/dL/mo). In regression models evaluated with SCr as the dependent variable versus post-OLT time, no significance was observed (P = .130). The average rate of eGFR change after OLT was -0.462 ± 0.883 mL/min/mo. By calculating the per-patient slope, the average rate of eGFR change was -0.009 ± 0.0026 mL/min (-0.0004 ± 0.0012 mL/min/mo). In the regression models evaluated with eGFR as dependent variable versus post-OLT time, no significance occurred (P = .168). By applying the regression prediction to SCr at 3 to 5 versus the 1 to 2 post-OLT measurements, we noted 3 male liver recipients (MLR) whose SCr values were significantly higher than the predicted values: MLR1: P = .048 at measurement 4; MLR2: P = .019 at measurement 4; and MLR3: P = .017 at measurement 5. Conversely, we did not observed a significant difference between observed versus predicted eGFR values. Clinical decisions on immunosuppressive treatments for liver recipients should be determined also on the basis of the series of post-OLT kidney function, which should be studied with rigorous evaluation of fitted regression models.

Long-term outcome after liver transplantation

Liver transplantation is a life-saving therapy for patients with end-stage liver disease, acute liver failure, and liver tumors. Over the past 4 decades, improvements in surgical techniques, peritransplant intensive care, and immunosuppressive regimens have resulted in significant improvements in short-term survival. Focus has now shifted to addressing long-term complications and improving quality of life in liver recipients. These include adverse effects of immunosuppression; recurrence of the primary liver disease; and management of diabetes, hypertension, dyslipidemia, obesity, metabolic syndrome, cardiovascular disease, renal dysfunction, osteoporosis, and de novo malignancy. Issues such as posttransplant depression, employment, sexual function, fertility, and pregnancy must not be overlooked, as they have a direct impact on the liver recipient's quality of life. This review summarizes the latest data in long-term outcome after liver transplantation.

[Retrospective comparative study between sevoflurane and propofol in maintaining anaesthesia during liver transplant: Effects on kidney and liver function]

OBJECTIVE

To compare the post-operative effects of sevoflurane versus propofol on liver and kidney function while maintaining anaesthesia in the orthotopic liver transplant (OLT), as well as to analyse the short-term survival as regards these functions.

PATIENTS AND METHODS

A retrospective analysis was conducted on patients subjected to an OLT between January 2002 and December 2009. Patients on pre-transplant haemodialysis, re-transplants, and hepatorenal transplants were excluded. The incidence of acute renal failure, initial dysfunction of the graft, reperfusion syndrome, rejection, and the transaminase peak depending value depending on the hypnotic used, were recorded.

RESULTS

About one-third (31.2%) of the patients developed acute renal failure and 11.9% an initial dysfunction, with no differences between the groups. There was a tendency for a lower incidence of initial dysfunction of the graft in the sevoflurane group (8.6% compared to 12.8%), a lower transaminase peak (greater than 2000 U/L, 12.1% versus 15.9%), and a lower incidence of reperfusion syndrome (10.3% compared to 21.6%).

CONCLUSIONS

Despite the fact that the renal metabolism sevoflurane is elevated, we did not find any higher incidence of acute renal failure. Sevoflurane in the liver transplant anaesthesia is as least equally as safe propofol as regards renal function and liver function. New prospective studies are needed to clarify the possible effects of the hypnotic in liver transplant.

Renal-sparing immunosuppressive protocol using OKT3 after liver transplantation: a 19-year single-institution experience

Different renal-sparing immunosuppressive protocols have been used in liver transplantation. At our institution, muromonab-CD3 (OKT3) is used in patients with acute renal failure (ARF), along with a delay in starting a calcineurin inhibitor. This study was conducted to compare outcomes in liver transplant patients with ARF who received OKT3 and those who did not. From 1988 to 2007, ARF was present in 1685 of 2587 patients (65%). OKT3 was used in 109 patients (OKT3 group). The control group (1416 patients) received a low-dose calcineurin inhibitor. The OKT3 group was more critically ill. In spite of this, the OKT3 group patients who were on renal replacement therapy (RRT) achieved long-term survival similar to that of the control group on RRT. Among the patients who were not on RRT, the OKT3 group had a higher complete recovery rate, but this did not translate into improved long-term survival. Bacterial and fungal infections were more common in the OKT3 group; however, there was no increased risk of malignancy or death from hepatitis C recurrence. The use of OKT3 in patients with ARF allowed more critically ill patients on RRT to achieve survival rates similar to those of patients who did not receive OKT3.

The use of terlipressin during living donor liver transplantation: Effects on systemic and splanchnic hemodynamics and renal function

OBJECTIVES

To assess the effect of the intraoperative use of terlipressin on splanchnic hemodynamics and postoperative renal function in patients undergoing liver transplantation.

DESIGN

Open-label, prospective, randomized study.

SETTING

Single-center study.

PATIENTS

Thirty patients who underwent elective, living-donor liver transplantation with portal pressure >20 mm Hg.

INTERVENTIONS

Patients were assigned randomly to one of two equal groups. The control group received saline, whereas the treatment group (TP group) received an initial bolus dose of terlipressin (1 mg over 30 mins) followed immediately by a continuous infusion of 2 μg·kg(-1)·h(-1) for 48 hrs.

MEASUREMENTS AND MAIN RESULTS

Portal pressure and gas exchange (radial artery, portal vein, and hepatic vein, blood gas analyses, and lactate concentration) were assessed at baseline (after ligation of the hepatic artery) and 2 hrs after drug administration. Systemic hemodynamic data and calculated tissue oxygenation parameters were compared throughout the procedure. Renal function was assessed by measurement of serum cystatin C after induction of anesthesia and on the first 2 days postoperatively. After the infusion of terlipressin, portal venous pressure decreased significantly from 26.3 ± 3.3 to 21.3 ± 3.6 mm Hg (p < .001). The mean arterial pressure and systemic vascular resistance were significantly higher in the TP group than in the control group, whereas heart rate and cardiac index were comparable between the groups. Portal and hepatic base excess, and the level of serum lactate, did not differ between the two groups. The serum levels of both cystatin C and creatinine were significantly higher in the control group than in the TP group on postoperative day 2.

CONCLUSION

Perioperative use of terlipressin abrogates the early postoperative decline in renal function of patients who have chronic liver disease and undergo liver transplantation without any detrimental effect on hepatosplanchnic gas exchange and lactate metabolism.

Sphingosine-1-phosphate reduces hepatic ischaemia/reperfusion-induced acute kidney injury through attenuation of endothelial injury in mice

AIM

Hepatic ischaemia/reperfusion injury (IRI) frequently complicates acute kidney injury (AKI) during the perioperative period. This study was to determine whether hepatic IRI causes AKI and the effect of the sphingosine-1-phosphate (S1P) on AKI.

METHODS

S1P and vehicle were given to mice before ischaemia and mice were subjected to hepatic IRI. Plasma creatinine (PCr), alanine transaminase (ALT), urinary neutrophil gelatinase-associated lipocalin (NGAL) and renal histological changes were determined. As a marker of endothelial injury, vascular permeability was measured. The effect of VPC 23019, a S1P(1) receptor antagonist, was also assessed.

RESULTS

Hepatic IRI resulted in liver injury (increased ALT) and systemic inflammation. Kidneys showed elevated inflammatory cytokines, leucocyte infiltration, increased vascular permeability, tubular cell apoptosis and increased urinary NGAL, although PCr did not increase. Pretreatment with S1P resulted in an attenuation of systemic inflammation and kidney injury without any effect on plasma ALT or peripheral lymphocytes. The protective effect of S1P was partially reversed by VPC 23019, suggesting the important contribution of the S1P/S1P(1) pathway to protect against hepatic IRI-induced AKI.

CONCLUSION

The study data demonstrate the important contribution of systemic inflammation and endothelial injury to AKI following hepatic IRI. Modulation of the S1P/S1P(1) receptor pathway might have some therapeutic potential in hepatic IRI-induced kidney injury.

Study protocol: a pilot study to determine the safety and efficacy of induction-therapy, de novo MPA and delayed mTOR-inhibition in liver transplant recipients with impaired renal function. PATRON-study

BACKGROUND

Patients undergoing liver transplantation with preexisting renal dysfunction are prone to further renal impairment with the early postoperative use of Calcineurin-inhibitors. However, there is only little scientific evidence for the safety and efficacy of de novo CNI free "bottom-up" regimens in patients with impaired renal function undergoing liver transplantation. This is a single-center study pilot-study (PATRON07) investigating safety and efficacy of CNI-free, "bottom-up" immunosuppressive (IS) strategy in patients undergoing liver transplantation (LT) with renal impairment prior to LT.

METHODS/DESIGN

Patients older than 18 years with renal impairment at the time of liver transplantation eGFR < 50 ml/min and/or serum creatinine levels > 1.5 mg/dL will be included. Patients in will receive a CNI-free combination therapy (basiliximab, MMF, steroids and delayed Sirolimus). Primary endpoint is the incidence of steroid resistant acute rejection within the first 30 days after LT. The study is designed as prospective two-step trial requiring a maximum of 29 patients. In the first step, 9 patients will be included. If 8 or more patients show no signs of biopsy proven steroid resistant rejection, additional 20 patients will be included. If in the second step a total of 27 or more patients reach the primary endpoint the regimen is regarded to be safe and efficient.

DISCUSSION

If a CNI-free-"bottom-up" IS strategy is safe and effective, this may be an innovative concept in contrast to classic top-down strategies that could improve the patient short and long-time renal function as well as overall complications and survival after LT. The results of PATRON07 may be the basis for a large multicenter RCT investigating the new "bottom-up" immunosuppressive strategy in patients with poor renal function prior to LT.http://www.clinicaltrials.gov-identifier: NCT00604357.

Scoring short-term mortality after liver transplantation

Liver transplantation can prolong survival and improve the quality of life of patients with end-stage liver disease. This study retrospectively reviewed the medical records of 149 patients who had received liver transplants in a tertiary care university hospital from January 2000 to December 2007. Demographic, clinical, and laboratory variables were recorded. Each patient was assessed by 4 scoring systems before transplantation and on postoperative days 1, 3, 7, and 14. The overall 1-year survival rate was 77.9%. The Sequential Organ Failure Assessment (SOFA) score had better discriminatory power than the Child-Pugh points, Model for End-Stage Liver Disease score, and RIFLE (risk of renal dysfunction, injury to the kidney, failure of the kidney, loss of kidney function, and end-stage kidney disease) criteria. Moreover, the SOFA score on day 7 post-liver transplant had the best Youden index and highest overall correctness of prediction for 3-month (0.86, 93%) and 1-year mortality (0.62, 81%). Cumulative survival rates at the 1-year follow-up after liver transplantation differed significantly (P < 0.001) between patients who had SOFA scores < or = 7 on post-liver transplant day 7 and those who had SOFA scores > 7 on post-liver transplant day 7. In conclusion, of the 4 evaluated scoring systems, only the SOFA scores calculated before liver transplantation were statistically significant predictors of 3-month and 1-year posttransplant mortality. SOFA on post-liver transplant day 7 had the best discriminative power for predicting 3-month and 1-year mortality after liver transplantation.

The safety of modern hydroxyethyl starch in living donor liver transplantation: a comparison with human albumin

BACKGROUND

Intravascular volume replacement therapy is an important issue in the perioperative management of liver transplantation. There is paucity of data on the safety of hydroxyethyl starch (HES) in patients undergoing liver transplantation. We evaluated the safety of a new HES 130/0.4 in the perioperative management of liver transplantation, with a special emphasis on renal function.

METHODS

Forty patients undergoing living donor liver transplantation were prospectively randomized into two groups. Patients in the ALB group (n = 20) received 5% human albumin. Patients in the HES group (n = 20) received third generation HES (6% HES 130/0.4). Total colloid administration was limited to 50 mL x kg(-1) x d(-1). The volume was given to maintain pulmonary artery occlusion pressure or central venous pressure between 5 and 7 mm Hg. If additional fluids were required, balanced crystalloid solution was used. Anesthetic and surgical techniques were standardized. Serum creatinine and cystatin C plasma levels were measured from arterial blood samples after induction of anesthesia, at the end of surgery, and on the first 4 postoperative days.

RESULTS

All 40 enrolled patients completed the study. Demographic and intraoperative variables were comparable in both groups. Postoperatively, the mean +/- sd volume was 6229 +/- 1140 mL and 4636 +/- 1153 mL in HES and ALB groups, respectively (P = 0.003). There was significantly greater [corrected] net cumulative fluid balance in the HES [corrected] group 3047 +/- 2000 [corrected] mL compared with the ALB group 1100 +/- 900 [corrected] mL, P = 0.029. Serum creatinine, creatinine clearance, and cystatin C plasma levels showed no significant differences between the two groups. One patient in each group developed acute renal failure requiring renal replacement therapy.

CONCLUSION

The use of HES 130/0.4 as an alternative to human albumin resulted in equivalent renal outcome after liver transplantation.

Calcineurin inhibitor minimization protocols in liver transplantation

Liver transplant recipients are at increasingly high risk for suffering from impaired renal function and probable need of renal replacement therapy. Extended criteria organs and transplantation of patients with higher model for end-stage liver disease scores further increase this problem. Acute and chronic nephrotoxicity are the trade-off in immunosuppression with potent calcineurin inhibitors (CNIs). As a good renal function is associated with better graft and patient survival, CNI minimization protocols have been developed. Current strategies to overcome CNI toxicity include reduction or withdrawal of CNIs concurrently with switching over to mammalian target of rapamycin inhibitor or mycophenolate mofetil (MMF)-based regimens. This strategy caused an improvement in renal function in a significant number of liver transplantation patients according to several studies. However, total CNI avoidance seems to result in higher rejection rates. To prevent chronic renal dysfunction in patients prone to or with acute renal failure, CNI delay - with induction therapy for bridging - followed by low-dose CNI in combination with MMF are proven strategies without risking higher rejection rates. An individualized, tailor-made immunosuppressive regime, with a special focus on renal function is recommended. This review gave an overview on CNI minimization protocols in liver transplantation also focusing on recently analyzed studies.

Impact of renal failure on liver transplantation survival

Renal failure after orthotopic liver transplantation (OLT) is a common complication (ranging from 12% to 70%) associated with worse outcomes, particularly when it requires renal replacement therapy (RRT). Renal dysfunction is a common scenario among waiting list patients. It can lead to a worse prognosis after OLT, due to an increased incidence of postoperative renal failure. The aim of this study was to analyze the incidence of renal failure after OLT, its relationship to pretransplant renal dysfunction, and its impact on outcomes. We analyzed data collected prospectively from 152 consecutive OLTs in 139 patients performed by the same team from March 2003 to November 2007. Exclusion criteria for 34 cases included transplantation due to acute liver failure, combined liver-kidney transplantation, retransplantation, and patients who died up to 2 days posttransplantation. Based on creatinine clearance (CCr) calculated at the time of OLT, the 118 patients were classified in two groups: group I, normal pre-OLT renal function (CCr > or = 70 mL/min) versus group II, pre-OLT renal failure (CCr < 70 mL/min). Each group was analyzed according to the development of post-OLT renal failure, being classified as subgroup A (normal renal function post-OLT), subgroup B (mild renal impairment post-OLT-serum creatinine level between 2.0 and 3.0 mg/dL or doubled basal value up to 3.0 mg/dL) versus subgroup C (severe renal impairment post-OLT-serum creatinine level > or = 3.0 mg/dL or utilization of RRT). The overall incidence of post-OLT renal impairment was 41.52% with RRT in 22 patients (18.64%). Group II patients showed a greater incidence of post-OLT renal failure when compared with other patients (P < .05), but without a statistical difference when compared according to RRT requirement. Comparison of average hospital stay was similar between groups I and II, and also among its subgroups (A, B, and C, respectively). There was no statistical difference in early (30-day) and 1-year survival rates between groups I and II. Comparing all subgroups for early and 1-year survival, we observed that patients who developed severe renal failure post-OLT (subgroups I-C and II-C) showed worse outcomes compared with other patients (subgroups I-A, I-B, II-A, and II-B), respectively 95.29% versus 69.69% and 86.95% versus 41.66% for early and 1-year survivals (P < .001). In conclusion, our findings suggested that patients who developed severe renal failure post-OLT, independent of pretransplant renal function, showed worse outcomes.

A new serum cystatin C-based equation for assessing glomerular filtration rate in liver transplantation

BACKGROUND

Cystatin C (CysC) has been identified to be an alternative marker of glomerular filtration rate (GFR), but no CysC-based equation has been developed for patients receiving liver transplantation.

METHODS

Serum CysC and (99m)Tc-DTPA clearance (true GFR) were measured simultaneously on post-transplant days 1, 4 and 7. A new equation was constructed based on an observation group of 30 patients and its predictive ability was compared with three other CysC-based equations (Hoek, Filler and Larsson) based on a validation group of 30 patients.

RESULTS

The new equation for calculating GFR was defined as 19.12+96.21x(1/CysC) and the derived GFR was estimated at 97.4+/-30.2 mL/min/1.73 m(2) and was close to the true GFR (96.8+/-32.8 mL/min/1.73 m(2)). Estimates of GFR by Hoek, Filler and Larsson formulas (61.4+/-25.4, 73.8+/-31.9 and 61.3+/-29.6mL/min/1.73 m(2), respectively) differed significantly from the true GFR. Correlation between the true GFR and all formulas showed no significant difference. Bias was neglectable for the new equation (mean difference: 0.6 mL/min/1.73 m(2)) but remarkable for the other three equations (mean difference: -22.9 to -35.4 mL/min/1.73 m(2)). Accuracy within 10%, 30% and 50% of the true GFR for the new equation (30.0%, 76.7% and 93.3%) was significantly higher than those of the other three equations (p<0.001 for all).

CONCLUSIONS

A new serum CysC-based equation was established in this study and it was shown to be accurate in estimating GFR after liver transplantation, compared to the formulas of Hoek, Filler and Larsson.

Alternative definition of acute kidney injury following liver transplantation: based on serum creatinine and cystatin C levels

OBJECTIVE

The aim of this study was to verify the estimation and the predictive abilities of serum creatinine (Cr), serum cystatin C (Cys C), and related formulas for acute kidney injury (AKI).

PATIENTS AND METHODS

Thirty patients who underwent cadaveric donor liver transplantation were enrolled in this prospective study. Glomerular filtration rate (GFR) was assessed by the 99mTc DTPA clearance method and estimated by Cr-predicted clearances (Cockcroft-Gault method [CG] and abbreviated Modification of Diet in Renal Disease equation [MDRD]) as well as by 3 other Cys C-based formulas (Hoek, Filler, and Larsson). AKI was confirmed as GFR<80 mL/min/1.73 m2 in the first posttransplantation week.

RESULTS

GFR was significantly correlated with reciprocal Cr, reciprocal Cys C, and the 5 formulas (P<.001 for all). The receiver operating characteristic (ROC) area of Cys C was larger than that of Cr (.937 vs .794, P<.05). ROC area of Hoek, or Filler or Larsson was also larger than that of CG or MDRD (.937, .935, .937 vs .802, .849, P<.05 for all). ROC analysis showed the cutoff values were 1.0 mg/dL for Cr and 1.57 mg/L for Cys C. Hoek, Filler, and Larsson equations all underestimated AKI; their optimal cutoff values should be adjusted to 47, 56, and 44 mL/min/1.73 m2, respectively.

CONCLUSION

Cys C is a better predictor of AKI than Cr. A value of more than 1.57 mg/L might be considered a new definition of AKI.

A novel prognostic model based on serum levels of total bilirubin and creatinine early after liver transplantation

BACKGROUND/AIM

We aim to evaluate the impact of early renal dysfunction (ERD), early allograft dysfunction (EAD) on post-transplant mortality, and further explore a simple and accurate model to predict prognosis.

PATIENTS

A total of 161 adult patients who underwent liver transplantation for benign end-stage liver diseases were enrolled in the retrospective study. Another 38 patients were used for model validation.

RESULTS

Poor patient survival was associated with ERD or EAD. A post-transplant model for predicting mortality (PMPM) based on serum levels of total bilirubin and creatinine at 24-h post-transplantation was then established according to multivariate logistic regression. At 3 months, 6 months and 1 year, the area under receiver operating characteristic curves (AUC) of PMPM score at 24-h post-transplantation (0.876, 0.878 and 0.849, respectively) were significantly higher than those of pre-transplant model for end-stage liver diseases (MELD) score (0.673, 0.674 and 0.618, respectively) or the post-transplant MELD score at 24-h post-transplantation (0.787, 0.787 and 0.781, respectively) (P<0.05). Patients with PMPM score -1.4 (high-risk group, n=47) (P<0.001). The patients in the high-risk group showed a relatively good outcome if their PMPM scores decreased to

CONCLUSION

The PMPM score could effectively predict short- and medium-term mortality in liver transplant recipients.

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Key Words Collapse

MESH Headings

• Adult
• Bilirubin/blood
• Biomarkers/blood
• Creatinine/blood
• Follow-Up Studies
• Humans
• Incidence
• Kidney Diseases/blood
• Kidney Diseases/mortality
• Liver Diseases/blood
• Liver Diseases/mortality
• Liver Diseases/surgery
• Liver Failure/blood
• Liver Failure/mortality
• Liver Transplantation
• Logistic Models
• Male
• Middle Aged
• Models, Biological
• ROC Curve
• Reproducibility of Results
• Retrospective Studies
• Risk Assessment
• Severity of Illness Index
• Time Factors
• Treatment Outcome

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Grants Collapse

Affiliation(s)

Xiao Xu Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
Qi Ling
Jian Wu
Jun Chen
Feng Gao
Xiao-Ning Feng
Shu-Sen Zheng

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Intra-abdominal hypertension is an independent cause of acute renal failure after orthotopic liver transplantation

An independent association between acute renal failure (ARF) and intra-abdominal hypertension (IAH) after liver transplantation has not been established previously. The aim of this retrospective study was to understand the role of IAH as an independent risk factor for ARF in the early postoperative period. This study involved 62 subjects who underwent liver transplantation. Intra-abdominal pressure (IAP) was measured in the first three days after surgery by using the urinary bladder technique. An IAP of at least 20 mmHg per day was defined as IAH. Clinical parameters between group IAH and group NO-IAH were compared in terms of the incidence of ARF, blood creatinine levels, blood urea nitrogen (BUN) levels, urine volume per hour and glomerular filtration gradient (GFG). Hemodynamic variations were recorded in the first three postoperative days between group ARF and group NO-ARF. The perioperative suspected risk factors of ARF were determined for statistical evaluation using correlation coefficients and logistic regression analysis. In group IAH, 45.8% patients developed ARF as against 7.9% in group NO-IAH; GFG was significantly lower at 0-72 h after surgery; and blood creatinine levels, BUN levels, urine volume per hour were significantly different at 24-72 h after surgery compared with group NO-IAH. The patients with ARF were not significantly different from those without ARF in terms of central venous pressure, pulmonary artery pressure and mean arterial pressure (MAP) in the first three postoperative days despite a significant increase in heart rate at 24-72h after operation. Postoperative IAH, intraoperative MAP and intraoperative blood transfusion volume of more than 15 U were found to be independent risk factors for ARF. IAH impaired renal function and was an independent risk factor for ARF after liver transplantation. Routine measurement should be taken to monitor IAP every eight hours postoperatively.