Incidence and factors predictive of acute renal failure in patients with advanced liver cirrhosis

Kidney Outcomes Following Utilization of Molecular Adsorbent Recirculating System

Introduction

Molecular adsorbent recirculating system (MARS) is an extracorporeal system combining conventional veno-venous hemodiafiltration and adsorption to provide rescue support in fulminant hepatic failure. Acute kidney injury (AKI) is common in patients with hepatic failure warranting continuous kidney replacement therapy (CKRT). Our primary aim was to characterize a cohort of patients who received MARS therapy and examine kidney events given the current paucity of available data.

Methods

Patients initiating MARS in a tertiary care setting from January 2014 through December 2020 were assessed for treatment indications, transplantation, CKRT, kidney recovery, and death. Data was collected using the REDCAP software.

Results

A total of 49 patients (67% female; 75% White) received MARS therapy with 29 patients (59%) requiring concomitant CKRT. Hepatic encephalopathy (HE) was the most common indication for MARS initiation (55%). In-hospital mortality was 41% (12/29) among patients who received CKRT versus 10% (2/20) among those not requiring CKRT (relative risk [RR] 4.15, 95% confidence interval [CI] 1.04 to 16.52, P = 0.044); this persisted following adjustment for prespecified patient characteristics (all RR ≥ 3.76, all P ≤ 0.060). One-year mortality post-MARS initiation was high overall but highest among the CKRT group (59% [17/29] vs. 25% [5/20] unadjusted RR 2.92, 95% CI 1.08 to 7.94, P = 0.035). Liver transplant after MARS occurred in 41% of patients (20/49). After CKRT, 39% of patients (9/29) recovered kidney function prior to hospital discharge.

Conclusions

Patients requiring MARS frequently have AKI warranting the use of concomitant CKRT, which is associated with a high rate of in-hospital and 1-year mortality.

Urinary Neutrophil Gelatinase-associated Lipocalin as a Diagnostic and Prognostic Marker for Acute Kidney Injury in Hospitalized Cirrhotic Patients: A Study from North Indian Population

Background

A serious problem in cirrhosis is acute renal injury. The study aimed to examine the urinary neutrophil gelatinase-associated lipocalin (uNGAL) as a diagnostic and prognostic marker of acute kidney injury (AKI) in cirrhotic patients.

Methods

A prospective study was carried out over a period of 1 year. A total of 490 patients suffering from cirrhosis who visited an indoor hospital were screened, and after the exclusion, a total of 90 subjects admitted to the medicine intensive care unit (MICU) fulfilling inclusion criteria were enrolled. Those having a history of renal diseases, on nephrotoxic drugs, in septic shock, peritonitis, UTI, and no urine output were excluded. On admission, for the estimation of uNGAL, urinary levels of sodium, creatinine, fresh urine samples were obtained, and blood samples were taken for serum creatinine estimation.

Results

Out of 90 patients, 33.3% did not develop AKI, and 66.7% developed AKI. Urinary neutrophil gelatinase-associated lipocalin levels were six times higher in patients with acute tubular necrosis (259.08 ± 118.41 ng/mL) and three times higher in Hepatorenal syndrome (HRS)-AKI (124.97 ± 16.38) as compared with patients with normal kidney function (39.76 + 5.7). Those who died had a higher uNGAL (171.6 ng/mL) in comparison to those who survived (133.7 ng/mL). At a cutoff value of ≥114.9 (ng/mL), urinary NGAL represents a sensitivity of 86.92% and specificity of 100% to diagnose AKI and AUC 0.966 (95% CI: 0.919-0.990) in cirrhotic patients.

Conclusion

Urinary NGAL is good for diagnosing AKI and is a marker to distinguish the types of AKI in liver cirrhosis.

How to cite this article

Patel ML, Shyam R, Chaudhary A, Sachan R, Ali W. Urinary Neutrophil Gelatinase-associated Lipocalin as a Diagnostic and Prognostic Marker for Acute Kidney Injury in Hospitalized Cirrhotic Patients: A Study from North Indian Population. Indian J Crit Care Med 2023;27(8):545-551.

Recent advances in pathophysiology, diagnosis and management of hepatorenal syndrome: A review

Hepatorenal syndrome with acute kidney injury (HRS-AKI) is a form of rapidly progressive kidney dysfunction in patients with decompensated cirrhosis and/or acute severe liver injury such as acute liver failure. Current data suggest that HRS-AKI occurs secondary to circulatory dysfunction characterized by marked splanchnic vasodilation, leading to reduction of effective arterial blood volume and glomerular filtration rate. Thus, volume expansion and splanchnic vasoconstriction constitute the mainstay of medical therapy. However, a significant proportion of patients do not respond to medical management. These patients often require renal replacement therapy and may be eligible for liver or combined liver-kidney transplantation. Although there have been advances in the management of patients with HRS-AKI including novel biomarkers and medications, better-calibrated studies, more widely available biomarkers, and improved prognostic models are sorely needed to further improve diagnosis and treatment of HRS-AKI.

Distinct Subtypes of Hepatorenal Syndrome and Associated Outcomes as Identified by Machine Learning Consensus Clustering

BACKGROUND

The utilization of multi-dimensional patient data to subtype hepatorenal syndrome (HRS) can individualize patient care. Machine learning (ML) consensus clustering may identify HRS subgroups with unique clinical profiles. In this study, we aim to identify clinically meaningful clusters of hospitalized patients for HRS using an unsupervised ML clustering approach.

METHODS

Consensus clustering analysis was performed based on patient characteristics in 5564 patients primarily admitted for HRS in the National Inpatient Sample from 2003-2014 to identify clinically distinct HRS subgroups. We applied standardized mean difference to evaluate key subgroup features, and compared in-hospital mortality between assigned clusters.

RESULTS

The algorithm revealed four best distinct HRS subgroups based on patient characteristics. Cluster 1 patients (n = 1617) were older, and more likely to have non-alcoholic fatty liver disease, cardiovascular comorbidities, hypertension, and diabetes. Cluster 2 patients (n = 1577) were younger and more likely to have hepatitis C, and less likely to have acute liver failure. Cluster 3 patients (n = 642) were younger, and more likely to have non-elective admission, acetaminophen overdose, acute liver failure, to develop in-hospital medical complications and organ system failure, and to require supporting therapies, including renal replacement therapy, and mechanical ventilation. Cluster 4 patients (n = 1728) were younger, and more likely to have alcoholic cirrhosis and to smoke. Thirty-three percent of patients died in hospital. In-hospital mortality was higher in cluster 1 (OR 1.53; 95% CI 1.31-1.79) and cluster 3 (OR 7.03; 95% CI 5.73-8.62), compared to cluster 2, while cluster 4 had comparable in-hospital mortality (OR 1.13; 95% CI 0.97-1.32).

CONCLUSIONS

Consensus clustering analysis provides the pattern of clinical characteristics and clinically distinct HRS phenotypes with different outcomes.

Consensus on the management of complications of cirrhosis of the liver in pediatrics

The Asociación Mexicana de Hepatología A.C. carried out the Consensus on the Management of Complications of Cirrhosis of the Liver in Pediatrics to provide physicians with useful information for treating said complications. A group of pediatric gastroenterologists and experts in nutrition, nephrology, and infectious diseases participated and reviewed the medical literature. The Delphi method was applied to obtain the level of agreement on the statements that were formulated. The statements were sent to the participants to be analyzed and voted upon, after which they were discussed in virtual sessions, and the final versions were produced. The aim of the consensus results was to issue indications for the management of pediatric patients with liver cirrhosis, to prevent or control complications.

Albumin administration in patients with cirrhosis: Current role and novel perspectives

Mortality in cirrhosis is mostly associated with the development of clinical decompensation, characterized by ascites, hepatic encephalopathy, variceal bleeding, or jaundice. Therefore, it is important to prevent and manage such complications. Traditionally, the pathophysiology of decompensated cirrhosis was explained by the peripheral arterial vasodilation hypothesis, but it is currently understood that decompensation might also be driven by a systemic inflammatory state (the systemic inflammation hypothesis). Considering its oncotic and nononcotic properties, albumin has been thoroughly evaluated in the prevention and management of several of these decompensating events. There are formal evidence-based recommendations from international medical societies proposing that albumin be administered in individuals with cirrhosis undergoing large-volume paracentesis, patients with spontaneous bacterial peritonitis, those with acute kidney injury (even before the etiological diagnosis), and those with hepatorenal syndrome. Moreover, there are a few randomized controlled trials and meta-analyses suggesting a possible role for albumin infusion in patients with cirrhosis and ascites (long-term albumin administration), individuals with hepatic encephalopathy, and those with acute-on-chronic liver failure undergoing modest-volume paracentesis. Further studies are necessary to elucidate whether albumin administration also benefits patients with cirrhosis and other complications, such as individuals with extraperitoneal infections, those hospitalized with decompensated cirrhosis and hypoalbuminemia, and patients with hyponatremia.

Acute Kidney Injury in Patients with Liver Cirrhosis: Prevalence, Predictors, and In-Hospital Mortality at a District Hospital in Ghana

Background

Acute kidney injury (AKI) is one of the most severe complications of cirrhosis and portends an ominous prognosis with an estimated mortality of about 50% in a month and 65% within a year. Infection and hypovolemia have been found to be the main precipitating factors of AKI in liver cirrhosis. Early detection and treatment of AKI may improve outcomes. AKI in patients with liver cirrhosis in Ghana and their impact on inpatient mortality are largely unknown. This study was aimed at determining the prevalence, precipitating factors, predictors, and in-hospital mortality of AKI in patients with liver cirrhosis admitted to a district hospital in Ghana.

Methods

Consecutive hospitalized patients with liver cirrhosis from 1 January 2018 to 30 April 2020 were recruited. Patient's demographic data and clinical features were collected using a standardized questionnaire. Biochemical and haematological tests as well as abdominal ultrasound scans were done for all patients. All patients were then followed up until discharge or death.

Results

There were 117 (65.4%) males out of the 179 patients with a mean age of 49.94 and 45.84 years for those with and without AKI, respectively. The prevalence of AKI was 27.9% (50/179). Out of 50 participants with AKI, 64.0% (32/50) died, contributing 41.0% of all in-patient mortality amongst participants. There was a significant association between AKI and death (p ≤ 0.001). The major precipitating factors of AKI were infections (60.0%), hypovolemia (20.0%) due to gastrointestinal bleeding and gastroenteritis, and refractory ascites (16.0%). Alkaline phosphatase, INR, model for end-stage liver disease sodium, sodium, and blood urea nitrogen were independent predictors of AKI.

Conclusion

AKI was common among patients with liver cirrhosis with high in-patient mortality. Identification of these precipitants and independent predictors of AKI may lead to prompt and targeted treatment with reduction in patient mortality.

In-hospital mortality of hepatorenal syndrome in the United States: Nationwide inpatient sample

BACKGROUND

Hepatorenal syndrome (HRS) is a life-threatening condition among patients with advanced liver disease. Data trends specific to hospital mortality and hospital admission resource utilization for HRS remain limited.

AIM

To assess the temporal trend in mortality and identify the predictors for mortality among hospital admissions for HRS in the United States.

METHODS

We used the National Inpatient Sample database to identify an unweighted sample of 4938 hospital admissions for HRS from 2005 to 2014 (weighted sample of 23973 admissions). The primary outcomes were temporal trends in mortality as well as predictors for hospital mortality. We estimated odds ratios from multi-level mixed effect logistic regression to identify patient characteristics and treatments associated with hospital mortality.

RESULTS

Overall hospital mortality was 32%. Hospital mortality decreased from 44% in 2005 to 24% in 2014 (P < 0.001), while there was an increase in the rate of liver transplantation (P = 0.02), renal replacement therapy (P < 0.001), length of hospital stay (P < 0.001), and hospitalization cost (P < 0.001). On multivariable analysis, older age, alcohol use, coagulopathy, neurological disorder, and need for mechanical ventilation predicted higher hospital mortality, whereas liver transplantation, transjugular intrahepatic portosystemic shunt, and abdominal paracentesis were associated with lower hospital mortality.

CONCLUSION

Although there was an increase in resource utilizations, hospital mortality among patients admitted for HRS significantly improved. Several predictors for hospital mortality were identified.

The prognostic impact of different stages of acute kidney injury in patients with decompensated cirrhosis: a prospective cohort study

AIM

To assess the impact of the different stages of acute kidney injury (AKI) on the prognosis of patients hospitalized with decompensated cirrhosis.

METHODS

This was a prospective cohort study of consecutive patients admitted in two tertiary hospitals in southern Brazil. Participants were considered eligible if they were admitted for acute decompensation of cirrhosis. The main exposure factor was the onset of AKI. AKI stages were defined according the European recommendations. The outcomes evaluated were survival time and death rates at 28 and 90 days from hospital admission. A χ2 test was used to compare mortality between groups. Kaplan-Meier survival analyses were undertaken assessing time to event as days from AKI diagnosis to death or liver transplant.

RESULTS

Two hundred and five patients were included in the study, and 121 met the criteria for AKI. Patients with AKI 1b, AKI 2 and AKI 3 had higher 90-day mortality than patients without AKI (P = 0.008, P < 0.001 and P < 0.001, respectively). However, there was no difference in 90-day mortality when patients with AKI 1a were compared with those without AKI (P = 0.742). The mean survival of patients without AKI was higher than that of patients with AKI 1b (591.4 and 305.4 days, respectively, P = 0.015), while there was no significant difference between the mean survival of patients without AKI and that of patients with AKI 1a (591.4 and 373.6 days, respectively, P = 0.198).

CONCLUSION

Only AKI ≥1b seems to substantially impact mortality of patients hospitalized for acute decompensation of cirrhosis.

Predictors of Development of Hepatorenal Syndrome in Hospitalized Cirrhotic Patients with Acute Kidney Injury

Hepatorenal syndrome (HRS) is a type of acute kidney injury (AKI), occurring in patients with decompensated liver cirrhosis and is associated with high mortality. We aim to describe the predictors associated with the development of HRS in cirrhotic patients with AKI. We retrospectively analyzed 529 cirrhotic patient encounters with AKI across all Northwell Health institutions between 1 January 2015 and 31 December 2018. We performed multivariate analyses to determine independent predictors of development of HRS. Alcoholic cirrhosis was the most common identified etiology of cirrhosis. The mean Model for End-Stage Liver Disease Scorewas18 (±7). Ascites was the most commonly identified clinical feature of portal hypertension. Infection was identified in 38.4% of patients with urinary tract infection/pyelonephritis being the most common. Spontaneous bacterial peritonitis occurred in 5.9% of patients. The most common cause of AKI was pre-renal. Hepatorenal syndrome was identified in 9.8% of patient encounters. Predictors of HRS were history of ascites, serum creatinine >2.5 mg/dL, albumin <3 g/dL, bilirubin >2 mg/dL and spontaneous bacterial peritonitis. We demonstrate strong predictors for the development of HRS which can aid clinicians to attain an early diagnosis of HRS, leading to prompt and targeted management and improving outcomes.

Recovery From Acute Kidney Injury Requiring Dialysis in Patients With Cirrhosis: A Population-Based Study

RATIONALE & OBJECTIVE

The decision to initiate kidney replacement therapy (KRT) for acute kidney injury (AKI) in cirrhosis remains controversial as it is unclear which patients will benefit. We sought to characterize factors associated with recovery from AKI requiring KRT in patients with cirrhosis to inform shared clinical decision-making.

STUDY DESIGN

Population-based retrospective cohort study.

SETTING & PARTICIPANTS

Adult patients from Ontario, Canada identified, using administrative data, to have cirrhosis at the time of admission to hospital with AKI (based on serum creatinine) requiring KRT (01/01/2009-12/31/2016) and followed until 12/31/2017.

EXPOSURES

Demographics and comorbidities prior to admission.

OUTCOMES

Kidney recovery defined as the absence of KRT for at least 30 days.

ANALYTICAL APPROACH

The cumulative incidences of kidney recovery, death, and liver transplantation were calculated at 1, 3, 6, and 12 months and independent predictors of kidney recovery were evaluated using Fine and Gray competing risk regression models that generated subdistribution hazards ratios (sHR).

RESULTS

Overall, 722 patients were included (median age 61 years [IQR 54-68]; MELD-Na 26 [IQR 22-34]; 66% male; 52% had viral hepatitis, 25% non-alcoholic fatty liver disease, 18% alcohol-associated liver disease). The cumulative incidences of kidney recovery at 1, 3, 6, and 12 months were 3%, 22%, 25%, and 26%, respectively. Higher MELD-Na score (sHR 0.72 per 5 units, 95%CI 0.65-0.80), acute-on-chronic liver failure (sHR 0.61, 95%CI 0.43-0.86), and sepsis (sHR 0.57, 95%CI 0.41-0.81) were associated with a lower hazard of kidney recovery while those on a liver transplant waitlist (sHR 3.10, 95% CI 1.96-4.88) and who were admitted to a teaching hospital (sHR 1.48, 95%CI 1.05-2.08) were more likely to experience kidney recovery.

LIMITATIONS

Observational design, AKI etiology not identified.

CONCLUSIONS

Kidney recovery from KRT occurred in only one-quarter of patients and was very unlikely after 3-months. These findings provide information regarding prognosis that may guide decisions regarding KRT initiation and continuation.

Epidemiology of Sepsis-Associated Acute Kidney Injury in Beijing, China: A Descriptive Analysis

Background

Sepsis is the most common contributing factor towards development of acute kidney injury (AKI), which is strongly associated to poor prognostic outcomes. There are numerous epidemiological studies about sepsis-associated acute kidney injury (S-AKI), however current literature is limited with the majority of studies being conducted only in the intensive care unit (ICU) setting. The aim of this study was to assess the epidemiology of S-AKI in all hospitalized in-patients.

Methods

This was a retrospective population-based study using a large regional population database in Beijing city from January, 2005 to December, 2017. It included patients with S-AKI. Patients with pre-existing end-stage kidney disease (ESKD), previous history of kidney transplantation, or being pregnant were excluded. Patients’ demographic characteristics, incidence, risk factors and outcomes of S-AKI were analyzed. The contrast between different time periods, different levels of hospitals, and types of the hospitals (traditional Chinese medicine hospitals (TCMHs) and western medicine hospitals (WMHs)) was also compared using Mann–Whitney U-test.

Results

A total of 19,579 patients were included. The overall incidence of S-AKI in all in-patients was 48.1%. The significant risk factors by multivariate analysis for AKI included: age, male, being treated in a level-II hospital, pre-existing hypertension, chronic kidney disease (CKD), cirrhosis, atrial fibrillation (AF), ischemic heart disease (IHD), being admitted from emergency room, ICU admission, shock, pneumonia, intra-abdominal infection, bloodstream infection, respiratory insufficiency, acute liver injury, disseminated intravascular coagulation (DIC) and metabolic encephalopathy. The overall mortality rate in this cohort was 55%. The multivariate analysis showed that the significant risk factors for mortality included: age, being treated in a level-II hospital and TCMHs, being admitted from emergency room, pre-existing comorbidities (CKD, malignancy, cirrhosis and AF), shock, pneumonia, intra-abdominal infection, bloodstream infection, central nervous system (CNS) infection and respiratory insufficiency.

Conclusion

AKI is a common complication in patients with sepsis, and its incidence increases over time, especially when ICU admission is required. Exploring interventional strategies to address modifiable risk factors will be important to reduce incidence and mortality of S-AKI.

Clinical Outcomes of Acute Pancreatitis in Patients with Cirrhosis According to Liver Disease Severity Scores

BACKGROUND

Literature on acute pancreatitis (AP) outcomes in patients with cirrhosis is limited. We aim to investigate the mortality and morbidity of AP in patients with cirrhosis.

METHODS

We conducted a retrospective cohort study, and propensity score matching was done to match cirrhotic with non-cirrhotic patients on a 1:2 basis. Outcomes included inpatient mortality, organs failure, systemic inflammatory response syndrome, and length of hospital stay. We performed subgroup analysis of cirrhotics according to Child-Pugh and MELD scores. Multivariable logistic regression models were tested.

RESULTS

From 819 AP patients, cirrhosis prevalence was 4.9% (40). There was no significant difference between cirrhotics and non-cirrhotics for inpatient mortality (7.5% vs. 1.3%, p = 0.1), severe AP (17.5% vs. 7.5%), shock (7.9% vs. 3%), respiratory failure (10% vs. 3.8%), need for intensive care unit (15% vs. 6.3%), systemic inflammatory response syndrome (SIRS) on admission (22.5% vs. 32.5%), and SIRS on day 2 (25% vs. 15%). Cirrhotics had similar rates of pancreatic necrosis, ileus, BISAP score, Marshall score, admission hematocrit, BUN, and hospital length of stay. Finally, cirrhotics who had severe AP, required ICU, and/or die in-hospital appeared to have more severe liver diseases (Child-C, higher MELD score > 17) and had lower AP severity scores (BISAP < 3, Marshall scores < 2).

CONCLUSION

In our study, cirrhotics hospitalized with AP had similar morbidity and mortality when compared to non-cirrhotics.

Hepatorenal syndrome: pathophysiology, diagnosis, and management

Hepatorenal syndrome (HRS), the extreme manifestation of renal impairment in patients with cirrhosis, is characterized by reduction in renal blood flow and glomerular filtration rate. Hepatorenal syndrome is diagnosed when kidney function is reduced but evidence of intrinsic kidney disease, such as hematuria, proteinuria, or abnormal kidney ultrasonography, is absent. Unlike other causes of acute kidney injury (AKI), hepatorenal syndrome results from functional changes in the renal circulation and is potentially reversible with liver transplantation or vasoconstrictor drugs. Two forms of hepatorenal syndrome are recognized depending on the acuity and progression of kidney injury. The first represents an acute impairment of kidney function, HRS-AKI, whereas the second represents a more chronic kidney dysfunction, HRS-CKD (chronic kidney disease). In this review, we provide critical insight into the definition, pathophysiology, diagnosis, and management of hepatorenal syndrome.

Evolution of diagnostic criteria for acute kidney injury in patients with decompensated cirrhosis: A prospective study in a tertiary university hospital

BACKGROUND

Recently, changes in acute kidney injury (AKI) diagnostic criteria have been proposed (ICA-AKI criteria). However, in Brazil there is a paucity of data and analyses that evaluate AKI in patients with cirrhosis and determine the impact of the implemented AKI criteria changes. Therefore, this study sought to evaluate the incidence of AKI in patients with cirrhosis; to evaluate the agreement between traditional and ICA-AKI criteria; and to assess its clinical and laboratory characteristics, etiologies, risk factors and outcomes.

METHODS

This is a prospective cohort study in hospitalized patients with cirrhosis and acute decompensation. The total number of hospitalizations was evaluated using the PWP statistical model for recurring events; P values<0.05 were considered significant.

RESULTS

A total of 154 admissions of 75 patients were included in the study. Among the hospitalizations, 89 (57.79%) met the ICA-AKI criteria. There was substantial agreement between both AKI classifications (Kappa 0.7293). The main etiology of AKI was pre-renal (59.55%), followed by renal (26.96%) and hepatorenal syndrome (10.11%). A multivariate analysis uncovered risk factors for ICA-AKI, including the MELD score (P=0.0162, RR:1.055, 95% CI:1.010-1.101) and the use of furosemide (P=0.001,RR:2.360, 95% CI:1.417-3.931). A univariate analysis found an association between in-hospital mortality and serum creatinine (sCr)≥1.5mg/dL(P=0.0373), MELD (P=0.0296), bilirubin (P=0.0064), and infection (P=0.0045), while in the multivariate analysis, the bilirubin levels (P=0.0030, RR:1.077, 95% CI: 1.025-1.130) and the presence of shock (P=0.0002, RR:8.511, 95% CI: 2.746-26.377) were associated with in-hospital mortality. Among the hospitalizations with AKI, death was significantly associated with non-response to treatment and dialysis. Initial stage 1A-AKI had lower in-hospital mortality than stage 1B-AKI.

CONCLUSIONS

AKI incidence was high in this cohort of patients with decompensated cirrhosis, and substantial agreement between AKI definitions was observed. In-hospital mortality was associated with worse liver function, AKI, infection and the presence of shock. Also, sCr>1,5mg/dL remained an important prognostic factor.

Urinary neutrophil gelatinase-associated lipocalin determines short-term mortality and type of acute kidney injury in cirrhosis

Background and Aim

Acute kidney injury increases mortality in cirrhotic patients by four fold. This study aimed to determine the usefulness of urinary neutrophil gelatinase-associated lipocalin (uNGAL) for differential diagnosis for acute kidney injury and for predicting short-term mortality in cirrhotic patients.

Methods

We enrolled 94 patients of decompensated cirrhosis. uNGAL was measured upon hospital admission in all patients. Patients with urinary tract infection and anuria were excluded. Patients were followed for 30 days or until death.

Results

Ten (9%) patients had normal kidney function, 9 (11.37%) stable chronic kidney disease, 32 (29.50%) prerenal azotemia, 33 (36.37%) hepatorenal syndrome (HRS), and 10 (13.64%) intrinsic acute kidney injury (iAKI). Prerenal azotemia had lower median uNGAL values compared to HRS and iAKI (95.50 vs 465.00 vs 1217.50, P < 0.001). uNGAL levels were significantly higher in patients who died within 30 days (717.17 ± 494.26 vs 331.65 ± 313.65 ng/mL, P -0.0017). On univariate analysis, serum creatinine (sCr), uNGAL, Model for End-Stage Liver Disease (MELD) score on admission, and length of stay were significant, and on multivariate analysis, uNGAL and hepatic encephalopathy (HE) were significant in predicting mortality.

Conclusions

uNGAL at baseline serves as an early marker in differentiating HRS, prerenal AKI, and iAKI in cirrhotic patients, where sCr values are not useful. Patients with higher uNGAL levels had higher transplant-free mortality at 30 days.

Incidence, Mortality and Predictors of Acute Kidney Injury in Patients with Cirrhosis: A Systematic Review and Meta-analysis

Background and Aims: Acute kidney injury (AKI) is common in patients with cirrhosis but the incidence is heterogeneous among studies. We performed a meta-analysis to describe the incidence of AKI and its impact on patient mortality in patients with cirrhosis. We also evaluated the admission variables predicting development of AKI. Methods: A systematic search of various databases was performed up to November 2018. Meta-analyses were performed using random effects models. Results: Of 18,474 patients with cirrhosis from 30 selected studies, 5,648 developed AKI, with a pooled incidence of 29% (95% confidence interval [CI]: 28-30%, I ² of 99%). In-hospital mortality assessed in eight studies was six-fold higher among AKI patients, as compared to those without AKI (odds ratio [OR] 6.72, 95% CI: 3.47-13, p<0.0001, I ² of 70%). Three studies on patients admitted to intensive care showed about six-fold higher mortality among AKI patients (OR 5.90, 95% CI: 3.21-10.85, p>0.0001). Mortality remained significantly high, at days 30 and 90 and even at 1-year follow up after development of AKI. Of 12 admission variables analyzed, model for end-stage liver disease score, Child-Pugh-Turcotte stage C, presence of ascites, and presence of sepsis/septic shock were statistically significant risk factors for AKI. Conclusions: AKI occurred in about 29% of patients with cirrhosis and is associated with a six-fold increased risk of in-hospital mortality. Mortality remained high even in long-term follow-up of 1 year. Patients at risk for AKI development can be recognized at admission. Prospective studies are needed to develop strategies for improving outcome of these patients.

Evaluation of Renal Disease in Patients With Cirrhosis

Renal dysfunction in cirrhosis is common and is associated with increased mortality. Identifying and treating reversible causes of renal disease can significantly improve outcomes. The etiology, approach, and evaluation of renal disease in this group of patients is similar to the noncirrhosis patient, with a few specific caveats. Renal disease may be unrelated to the cause of cirrhosis (eg, prerenal acute kidney injury, acute tubular necrosis), occur as a manifestation of the same systemic disease responsible for the liver disease (eg, chronic viral hepatitis B and C infection) or as a consequence of cirrhosis (hepatorenal syndrome). Kidney impairment may be underrecognized in patients with cirrhosis due to over-reliance on creatinine-based glomerular filtration rate equations used in clinical practice. The first steps of evaluation for the renal disease include a thorough medical history to identify the underlying cause of cirrhosis and any potential trigger for renal dysfunction, physical examination, and review of prior laboratory records for baseline renal function. Renal imaging and urinalysis should be performed on all cirrhotic patients with renal dysfunction to establish the presence of urinary obstruction, chronicity and intrinsic renal disease.

2019 Clinical Update in Liver Transplantation

Liver transplantation continues be the standard for treatment of end-stage liver disease, and even with recent advances in organ preservation, the anesthetic management continues to require understanding of multiple organ systems beyond the liver. Multiple factors contribute to hemodynamic changes after reperfusion of the liver graft that anesthesiologists should be aware of before unclamping. Concomitant renal dysfunction in end-stage liver disease is not uncommon, and preparation for continuous renal replacement therapy may need to be considered in certain cases. Cardiac evaluation of liver transplantation patients with an emphasis on arrhythmias, including atrial fibrillation, can help prevent both intraoperative and postoperative complications detrimental to the patient and graft. Finally, combined liver and thoracic organ transplantations may be indicated for certain disease processes that affect multiple organs. These cases require an understanding of the surgical technique and acknowledgment that some goals of the procedures may be in direct opposition to each other.

Clinical outcomes of acute pancreatitis in patients with cirrhosis

BACKGROUND

AP outcomes in cirrhotic patients have not yet been studied. We aim to investigate the outcomes of cirrhotics patients with acute pancreatitis.

METHODS

The National Inpatient Sample (NIS) database (2003-2013) was queried for patients with a discharge diagnosis of AP and liver cirrhosis. Cirrhosis was further classified as compensated and decompensated using the validated Baveno IV criteria. Primary outcome was inpatient mortality. The analysis was adjusted for age, gender, race, Charlson comorbidity index (CCI), median income quartile, and hospital characteristics.

RESULTS

Over 2.8 million patients with acute pancreatitis were analyzed. Cirrhosis prevalence was 2.8% (80,093). Both compensated and decompensated cirrhosis subjects had significantly higher mortality. Highest odds ratios (OR) were: inpatient mortality (OR 3.4, P < 0.001), Shock (OR 1.5, P = 0.02), Ileus (OR: 1.3, p = 0.02, ARDS (OR 1.2, p = 0.03), upper endoscopy performed (OR 2.0, p < 0.001), blood transfusions (OR 3.1, p < 0.001), gastrointestinal bleed (OR 5.5, p < 0.001), sepsis (OR 1.3, p = 0.005), portal vein thrombosis (PVT) (OR 7.2, p < 0.001), acute cholecystitis (OR 1.3, p < 0.001). Interestingly, cirrhosis patients had lower hospital length of stay, (OR 0.16, p < 0.001), AKI (OR 0.93, p = 0.06), myocardial infarction (OR 0.31, p < 0.001), SIRS (OR 0.62, p < 0.001), parenteral nutrition requirement (OR 0.84, p = 0.002). Decompensated cirrhosis had higher inflation-adjusted hospital charges (+$3896.60; p < 0.001).

CONCLUSION

AP patients with cirrhosis have higher inpatient mortality, but it is unlikely to be due to AP severity as patients had lower incidence of SIRS and AKI. Higher mortality is possibly related to complications of cirrhosis and portal hypertension itself such as GI bleed, shock, PVT, AC and sepsis.

Emerging Threat: Changing Epidemiology of Hepatitis A and Acute Kidney Injury

In the past decade, hepatitis A has been considered a rare disease in the United States, largely due to targeted vaccination of at-risk children. Evolving epidemiology has resulted in decreasing immunity and increasing hepatitis A infections among adults who are more likely to experience severe disease. A surge in outbreaks has been noted in the past 2 years, resulting in a high volume of hepatitis A related hospitalizations and complications in otherwise healthy individuals. The traditional understanding that acute kidney injury is a rare extrahepatic manifestation is being challenged by the resurgence of hepatitis A in a more vulnerable population. This review examines the epidemiologic factors that contributed to current public health concern and the association between hepatitis A and acute kidney injury.

Refining the Role of Simultaneous Liver Kidney Transplantation

Adoption of the model for end-stage liver disease score by Organ Procurement and Transplant Network (OPTN) deceased donor liver allocation policy in 2002 has led to an increase in the number of simultaneous liver kidney (SLK) transplantation. Since kidney function recovery following liver transplantation is difficult to predict, allocation of the kidney for SLK transplantation thus far has not been based on much rationale and evidence. Lack of OPTN policy towards SLK organ allocation has resulted in great variations among transplant centers regarding SLK transplantation. Increasing use of kidneys towards SLK transplantation diverts deceased donor kidneys away from candidates awaiting kidney-alone transplantation. Recently OPTN/United Network of Organ Sharing has implemented medical eligibility criteria for adult SLK transplantation which also includes a concept of safety net. Implementation of the new policy is a move in a positive direction, providing consistency in our practice and evidence-based guidelines in selecting candidates for SLK transplantation. This policy needs to be monitored prospectively and modified based on new data that will emerge over time. This review outlines the literature on SLK transplantation and efforts towards developing rational policy on SLK organ allocation.

Excellent outcomes in combined liver-kidney transplantation: Impact of kidney donor profile index and delayed kidney transplantation

The positive impact of delayed kidney transplantation (KT) on patient survival for combined liver-kidney transplantation (CLKT) has already been demonstrated by our group. The purpose of this study is to identify whether the quality of the kidneys (based on kidney donor profile index [KDPI]) or the delayed approach KT contributes to improved patient survival. In total, 130 CLKTs were performed between 2002 and 2015, 69 with simultaneous KT (group S) and 61 with delayed KT (group D) (performed as a second operation with a mean cold ischemia time [CIT] of 50 ± 15 hours). All patients were categorized according to the KDPI score: 1%-33%, 34%-66%, and 67%-99%. Recipient and donor characteristics were comparable within groups S and D. Transplant outcomes were comparable within groups S and D, including liver and kidney CIT, warm ischemia time, and delayed graft function. Lower KDPI kidneys (<34%) were associated with increased patient survival in both groups. The combination of delayed KT and KDPI 1%-33% resulted in 100% patient survival at 3 years. These results support that delayed KT in CLKT improves patient survival. The combination of delayed KT and low KDPI offers excellent patient survival up to 3 years. Improved outcomes in the delayed KT group including high KDPI kidneys supports expansion of the donor pool with the use of more extended criteria donor and donation after circulatory death kidneys. Liver Transplantation 24 222-232 2018 AASLD.

Clinical characteristics and prognostic factors of liver cirrhosis patients with systemic inflammatory response syndrome

AIM

Our objective is to study the clinical characteristics of cirrhosis patients with SIRS and investigate its prognostic factors.

METHODS

We analyzed 285 consecutive patients and their data were evaluated retrospectively. Data were compared in patients with/without SIRS during hospitalization. Univariate and multivariate Cox regression analyses were undertaken separately for cirrhotic patients with SIRS to assess predictive factors for 90-day mortality.

RESULTS

The mortality was 38.24% (52/136) in patients with SIRS and 6.04% (9/149) in patients without SIRS for 90-day follow-up (P < 0.001). The univariate analysis showed gastrointestinal hemorrhage (P < 0.001), hepatic encephalopathy (P < 0.001), albumin <30 g/L (P < 0.037), creatinine (Cr) >175 µmol/L (P < 0.001), cholinesterase(ChE) activity <3000 U/L (P = 0.019), white blood cell count ≥10 000 (109/L) (P = 0.018), neutrophils ≥80% (P = 0.018), C-reactive protein (CRP) ≥25 mg/L (P < 0.001), procalcitonin ≥1.0 ng/mL (P = 0.007), Child-Pugh class C (P < 0.001), septicemia (P < 0.001), pulmonary infection (P < 0.001),multi-site infection (P = 0.001), acute-on-chronic liver failure (ACLF) (P < 0.001), and advanced hepatocellular carcinoma (HCC) (P < 0.001). In multivariate analysis, only Cr ≥175 µmol/L (hazard ratio [HR] = 2.768; confidence interval [CI], 1.53-5.04; P = 0.001), C-reactive protein ≥25 mg/L (HR = 3.179; CI, 1.772-7.03; P = 0.004), multi-site infection (HR = 19.427; CI, 7.484-50.431; P < 0.001), ACLF (HR = 7.308; CI, 3.048-17.521; P < 0.001), advanced HCC (HR = 2.523; CI, 1.019-6.248; P = 0.045) were independent predictors of 90-day mortality in cirrhotic patients with SIRS.

CONCLUSION

Cr ≥ 175 µmol/L, CRP ≥ 25 mg/L, multi-site infection, ACLF, and advanced HCC independently predicted a higher rate of 90-day mortality in liver cirrhosis with SIRS.

Biomarkers of Renal Injury in Cirrhosis: Association with Acute Kidney Injury and Recovery after Liver Transplantation

BACKGROUND

To define urine or serum biomarkers in predicting renal function recovery after liver transplantation (LT).

METHODS

Adults listed for LT (February 2011-July 2014) and with modified diet for renal disease-6 (MDRD-6) <60 mL/min provided urine/blood samples at baseline and serially until LT for biomarkers in serum (pg/mL) and urine (pg/mg creatinine).

RESULTS

Of 271 LT listed patients (mean age 57 years, 63% males, median listing MELD 17.5), 1 year acute kidney injury (AKI) probability was 49%, with odds of 1.3-, 3.0-, 4.6-, and 8.5-fold times for listing MELD 16-20, 21-25, 26-30, and >30, compared to MELD <16. Thirty-seven people died over 1 year from the time of listing, with twofold increased odds with AKI. Among 67 patients with MDRD <60, only urinary epidermal growth factor was different comparing AKI (increase in serum creatinine ≥0.3 mg/dL from baseline within past 3 months) vs. no AKI (2,254 vs. 4,253, p = 0.003). Differences between acute tubular necrosis (ATN) and hepatorenal syndrome could not be ascertained for a small sample of 3 patients with ATN. Analyzing 15 of 43 receiving LT and MDRD-6 <30 prior to LT, biomarkers were not different comparing 5 patients recovering renal function (MDRD-6 >50 mL/min) at 6 months vs. 10 without recovery.

CONCLUSIONS

AKI is common among LT listed patients, with a negative impact on transplant-free survival. Serum and urine biomarkers are not associated with the recovery of renal function after LT. Multicenter studies are suggested to (a) develop strategies to reduce the development of AKI and (b) derive novel biomarkers for use in accurately predicting renal recovery after LT.

Perioperative Management of Lactic Acidosis in End-Stage Liver Disease Patient

Lactic acidosis (LA) in end-stage liver disease (ESLD) patients has been recognized as one of the most complicated clinical problems and is associated with increased morbidity and mortality. Multiple-organ failure, associated with advanced stages of cirrhosis, exacerbates dysfunction of numerous parts of lactate metabolism cycle, which manifests as increased lactate production and impaired clearance, leading to severe LA-induced acidemia. These problems become especially prominent in ESLD patients, that undergo partial hepatectomy and, particularly, liver transplantation. Perioperative management of LA and associated severe acidemia is an inseparable part of anesthesia, post-operative and critical care for this category of patients, presenting a wide variety of challenges. In this review, lactic acidosis applied pathophysiology, clinical implications for ESLD patients, diagnosis, role of intraoperative factors, such as anesthesia and surgery-related, vasoactive agents impact, and also current treatment options and modalities have been discussed.

Severe symptomatic acute hyponatremia in traumatic brain injury responded very rapidly to a single 15 mg dose of oral tolvaptan; a Mayo Clinic Health System hospital experience - need for caution with tolvaptan in younger patients with preserved renal function

Tolvaptan is now well established as a potent pharmaceutical agent for symptomatic hyponatremia from syndrome of inappropriate antidiuretic hormone secretion (SIADH), congestive heart failure and liver cirrhosis. Previous studies had recruited older (63-65 years) patients with mild renal impairment (serum creatinine, 1.3-1.4 mg/dl). A 2012 report in the Journal of Neurology, Neurosurgery & Psychiatry described tolvaptan as a "lifesaving drug". A major outcome concern in the treatment of chronic hyponatremia is potentially fatal pontine demyelination from over-rapid correction of serum sodium >0.5 mEq/dL/h. The maximum reported correction of serum sodium within 24 hours was 13 mEq/L in a case of SIADH. We recently experienced the dramatic correction of hyponatremia at 1 mEq/dL/h over 18 hours, following 15 mg of oral tolvaptan in a 32-year old male patient with normal kidney function (serum creatinine 0.76 mg/dL), following traumatic brain injury (TBI). Tolvaptan is indeed an effective and life-saving drug for post-TBI hyponatremia. However, we strongly recommend the use of lower doses of tolvaptan (≤15 mg/d) in younger patients with more preserved renal function to avoid the development of life-threatening pontine demyelination.

[Acute Kidney Injury in Cirrhotic Patients with Portal Hypertension]

Acute kidney injury (AKI) is one of the most common manifestations encountered in clinical practice. It is associated with high morbidity and mortality in cirrhotic pre- and post-transplantation patients. Hepatorenal syndrome (HRS), a special form of AKI in cirrhotic patients, was recognized as a consequence of renal vasoconstriction from systemic/renal hemodynamic alterations developed in advanced cirrhosis with portal hypertension. Recently, multiple factors-such as infection/inflammation, underlying glomerulonephritis, bile cast, or increased abdominal pressure-have been considered to contribute to renal dysfunction in cirrhotic patients, which were presumed to induce HRS. Moreover, in addition to changing the definition of AKI in the nephrologic guidelines, the new AKI definition for early diagnosis and intervention based on characteristics of liver cirrhosis has been proposed in an international meeting. This article provides a comprehensive and recent review of AKI definition, laying out the topics in accordance with the pathophysiologic mechanisms and therapeutic interventions of AKI in cirrhotic patients with portal hypertension.

Acute renal injury after partial hepatectomy

Currently, partial hepatectomy is the treatment of choice for a wide variety of liver and biliary conditions. Among the possible complications of partial hepatectomy, acute kidney injury (AKI) should be considered as an important cause of increased morbidity and postoperative mortality. Difficulties in the data analysis related to postoperative AKI after liver resections are mainly due to the multiplicity of factors to be considered in the surgical patients, moreover, there is no consensus of the exact definition of AKI after liver resection in the literature, which hampers comparison and analysis of the scarce data published on the subject. Despite this multiplicity of risk factors for postoperative AKI after partial hepatectomy, there are main factors that clearly contribute to its occurrence. First factor relates to large blood losses with renal hypoperfusion during the operation, second factor relates to the occurrence of post-hepatectomy liver failure with consequent distributive circulatory changes and hepatorenal syndrome. Eventually, patients can have more than one factor contributing to post-operative AKI, and frequently these combinations of acute insults can be aggravated by sepsis or exposure to nephrotoxic drugs.

Comparison of Clinical Outcomes following Glue versus Polyvinyl Alcohol Portal Vein Embolization for Hypertrophy of the Future Liver Remnant prior to Right Hepatectomy

PURPOSE

To report outcomes after portal vein embolization (PVE) and right hepatectomy in patients receiving embolization with N-butyl cyanoacrylate (NBCA) glue + central AMPLATZER Vascular Plug (AVP; glue group) or polyvinyl alcohol (PVA) particles ± coils (PVA group).

MATERIALS AND METHODS

Between March 2008 and August 2013, all patients having PVE with NBCA + AVP or PVA ± coils before right hepatectomy were retrospectively reviewed; 85 patients underwent PVE with NBCA + AVP (n = 45) or PVA ± coils (n = 40). The groups were compared using Mann-Whitney U and χ² tests.

RESULTS

Technical success of embolization was 100%. Degree of hypertrophy (16.2% ± 7.8 vs 12.3% ± 7.62, P = .009) and kinetic growth rate (3.5%/wk ± 2.0 vs 2.6%/wk ± 1.9, P = .016) were greater in the glue group versus the PVA group. Contrast volume (66.1 mL ± 44.8 vs 189.87 mL ± 62.6, P < .001) and fluoroscopy time (11.2 min ± 7.8 vs 23.49 min ± 11.7, P < .001) were significantly less during the PVE procedure in the glue group. Surgical outcomes were comparable between groups, including the number of patients unable to go onto surgery (P = 1.0), surgical complications (P = .30), length of hospital stay (P = .68), and intensive care unit admissions (P = .71). There was 1 major complication (hepatic abscess) in each group after PVE.

CONCLUSIONS

PVE performed with NBCA + AVP compared with PVA ± coils resulted in greater degree of hypertrophy of the future liver remnant, less fluoroscopic time and contrast volume, and similar complication rates.

Acute Kidney Injury in Patients with Cirrhosis

Acute kidney injury (AKI) occurs commonly in patients with advanced cirrhosis and negatively impacts pre- and post-transplant outcomes. Physiologic changes that occur in patients with decompensated cirrhosis with ascites, place these patients at high risk of AKI. The most common causes of AKI in cirrhosis include prerenal injury, acute tubular necrosis (ATN), and the hepatorenal syndrome (HRS), accounting for more than 80% of AKI in this population. Distinguishing between these causes is particularly important for prognostication and treatment. Treatment of Type 1 HRS with vasoconstrictors and albumin improves short term survival and renal function in some patients while awaiting liver transplantation. Patients with HRS who fail to respond to medical therapy or those with severe renal failure of other etiology may require renal replacement therapy. Simultaneous liver kidney transplant (SLK) is needed in many of these patients to improve their post-transplant outcomes. However, the criteria to select patients who would benefit from SLK transplantation are based on consensus and lack strong evidence to support them. In this regard, novel serum and/or urinary biomarkers such as neutrophil gelatinase-associated lipocalin, interleukins-6 and 18, kidney injury molecule-1, fatty acid binding protein, and endothelin-1 are emerging with a potential for accurately differentiating common causes of AKI. Prospective studies are needed on the use of these biomarkers to predict accurately renal function recovery after liver transplantation alone in order to optimize personalized use of SLK.

Assessment of renal functions in patients of chronic liver disease

AIMS AND OBJECTIVES

Renal involvement in patients of chronic liver disease (CLD) is one of the dreaded complications associated with a steep rise in mortality and morbidity. Derangements in various homeostatic mechanisms in CLD leading to direct renal injury or circulatory compromise have been associated with renal impairment.

METHOD

Consecutive cirrhotic patients (n = 100) were included in the study. Structural and functional renal failure was identified and patients were classified into various renal syndromes pre renal, intra-renal and hepatorenal syndrome (HRS).

RESULTS

At the time of presentation, 37 patients had renal dysfunction. Thirty patients had pre-renal type of renal failure, six patients had intrinsic renal disease and one patient had structural renal disease. Patients with pre-renal type were further classified into volume responsive pre-renal failure and volume non responsive HRS. Five patients had features suggestive of HRS. Patients with decompensation such as portal hypertension (PHTN), jaundice, upper gastro-intestinal bleed and hepatic encephalopathy had significantly higher incidence of renal derangements as compared to their counterparts. Infection in the form of SBP and/or sepsis predisposed patients to develop renal dysfunction.

CONCLUSION

Renal impairment in patients with advanced liver disease is not an uncommon phenomenon and is more commonly associated with a more advanced disease. Presence of PHTN and various signs of decompensation increase the chances of renal derangements in these patients. In view of rising incidence of CLD and higher survival (due to better treatment options available), one should be vigilant for the renal derangements in these patients.

Acute Kidney Injury in Liver Disease: Role of Biomarkers

Acute kidney injury (AKI) is a common complication in patients with advanced cirrhosis and is associated with significant mortality. The most common etiologies of AKI in this setting are prerenal azotemia, acute tubular necrosis, and hepatorenal syndrome. Despite the overall poor outcomes of patients with cirrhosis and AKI, potentially efficacious therapies exist but must be tailored to the specific AKI etiology. Unfortunately, determining the etiology of AKI in the setting of cirrhosis is notoriously difficult. Many of the standard diagnostic tools, such as urine microscopy and the fractional excretion of sodium, have traditionally been ineffective. Novel biomarkers of kidney tubular injury may be able to assist with differential diagnosis and the appropriate targeting of treatments by distinguishing structural from functional causes of AKI. In recent studies, both urinary neutrophil gelatinase-associated lipocalin and interleukin-18 have shown the ability to distinguish hepatorenal syndrome from prerenal azotemia and acute tubular necrosis. In addition, multiple biomarkers, including neutrophil gelatinase-associated lipocalin and interleukin-18, have demonstrated the ability to independently predict both progression of AKI and mortality. Critically, recent research also indicated that commonly available tests, fractional excretion of sodium and proteinuria, may also be able to distinguish etiologies of AKI in cirrhosis, but diagnostic cutoffs must be re-conceptualized specifically to this unique AKI setting.

The Kidney in Pediatric Liver Disease

There is an intricate relationship between the liver and the kidney, with renal physiology and function intimately involved in many primary disorders of pediatric liver disease. The hemodynamic changes of progressive cirrhosis affect and are directly affected by changes in renal blood flow and renal handling of sodium and free water excretion. Resulting complications of worsening ascites, hyponatremia, and acute kidney injury frequently complicate the care of children with advanced liver disease and contribute significant morbidity and mortality. While liver transplantation may restore hemodynamic stability, nearly 40% of pediatric liver transplant recipients develop chronic kidney disease post-transplant and approximately 25% are left with clinical hypertension. This review seeks to provide a basic understanding of this relationship to enable the provision of optimal care to children with liver disease.

Employment of vasopressin receptor antagonists in management of hyponatraemia and volume overload in some clinical conditions

WHAT IS KNOWN AND OBJECTIVE

Hyponatraemia, the most common electrolyte imbalance occurring in hospitalized subjects, is usually classified as hypovolaemic, euvolaemic or hypervolaemic. Hyponatraemia is a predictor of death among subjects with chronic heart failure and cirrhosis. The inappropriate secretion of the antidiuretic hormone (AVP) seems to be of pivotal importance in the decline of serum sodium concentration in these clinical conditions. The objective of this review was to summarize recent progress in management of hyponatraemia in SIADH, cirrhosis and heart failure.

METHODS

Literature searches were conducted on the topics of hyponatraemia and vasopressin receptor antagonists, using PubMed, pharmaceutical company websites and news reports. The information was evaluated for relevance and quality, critically assessed and summarized.

RESULTS AND DISCUSSION

The initial treatment of severe hyponatraemia is directed towards the prevention or management of neurological manifestations and consists of an intravenous infusion of hypertonic saline. Fluid restriction is indicated in oedematous states. Diuretics alone or in combination with other specific drugs remain the main strategy in the management of volume overload in heart failure. In resistant cases, ultrafiltration can lead to effective removal of isotonic fluid preventing new episodes of decompensation; however, aquapheresis is associated with increased costs and other limits. In several trials, the efficacy of vasopressin receptor antagonists in euvolaemic patients (inappropriate antidiuretic hormone secretion) or in hypervolaemic hyponatraemia (chronic heart failure, cirrhosis) has been evaluated. It was found that vaptans, which promote aquaresis, were superior to a placebo in raising and maintaining serum sodium concentrations in these subjects.

WHAT IS NEW AND CONCLUSIONS

Combined with conventional therapy, vasopressin receptor antagonists (AVP-R antagonists) are able to increase the excretion of electrolyte-free water and the sodium concentration. Further studies are needed to assess efficacious outcomes of aquaresis compared with aquapheresis and with conventional therapy.

Review of Tolvaptan's Pharmacokinetic and Pharmacodynamic Properties and Drug Interactions

Tolvaptan is an arginine vasopressin (AVP) antagonist that acts to increase excretion of free water (aquaresis) in patients without introducing electrolyte abnormalities or worsening renal function. It works via blockade of vasopressin-2 receptors at the renal collecting duct. Since the approval of tolvaptan for the treatment of hypervolemic and euvolemic hyponatremia in 2009, new studies have been reported to better characterize its pharmacokinetic and pharmacodynamic profile of tolvaptan. This paper is a review of both these clinical studies, as well as previous literature, in order to help guide appropriate clinical use of tolvaptan in patients. With appropriate monitoring of serum sodium, tolvaptan may be safely dose escalated from 15 mg once daily to a maximum effective dose of 60 mg once daily for multiple days, to achieve optimal aqauretic effects. In terms of drug interactions, co-administration of moderate to potent CYP3A4 inhibitors and inducers should be avoided. Tolvaptan should also be co-administered with caution and proper monitoring in the presence of P-glycoprotein substrate and strong inhibitors. Co-administration of tolvaptan with diuretic therapy did not appear to alter the aquaretic effect of tolvaptan; and was shown to be safe and well tolerated.

Low-dose tolvaptan for the treatment of dilutional hyponatremia in cirrhosis: a case report and literature review

Dilutional hyponatremia is common in decompensated cirrhosis and can be successfully treated by tolvaptan, a vasopressin V2-receptor antagonist. Data were lacking regarding the effects of tolvaptan on cirrhotic patients with a Child-Pugh score of >10 and a serum sodium concentration of <120 mmol/L. We report a case of forties man with a 20-year history of chronic hepatitis B presenting with yellow urine and skin. Laboratory tests demonstrated prolonged prothrombin time, markedly elevated total bilirubin, severe hyponatremia, and a Child-Pugh score of >10. The patient was diagnosed with dilutional hyponatremia and was treated with recommended dosage tolvaptan at first. The serum concentration of sodium recover but the patient felt obviously thirsty. As the dosage of tolvaptan was decreased accordingly from 15 mg to 5 mg, the patient still maintained the ideal concentration of serum sodium. This case emphasizes that cirrhotic patient with higher Child-Pugh scores and serum sodium concentration of <120 mmol/L can be treated with lower dose of tolvaptan.

Intraoperative hemodialysis during liver transplantation: a decade of experience

Liver transplantation (LT) for patients with renal dysfunction is frequently complicated by major fluid shifts, acidosis, and electrolyte and coagulation abnormalities. Continuous renal replacement therapy (CRRT) has been previously shown to ameliorate these problems. We describe the safety and clinical outcomes of intraoperative hemodialysis (IOHD) during LT for a group of patients with high Model for End-Stage Liver Disease (MELD) scores. We performed a retrospective study at our institution of patients who underwent IOHD from 2002 to 2012. Seven hundred thirty-seven patients underwent transplantation, and 32% received IOHD. The mean calculated MELD score was 37, with 38% having a MELD score ≥ 40. Preoperatively, 61% were in the intensive care unit, 19% were mechanically ventilated, 43% required vasopressor support, and 80% were on some form of renal replacement therapy at the time of transplantation, the majority being on CRRT. Patients on average received 35 U of blood products and 4.8 L of crystalloids without significant changes in hemodynamics or electrolytes. The average urine output was 450 ml, and the average amount of fluid removal with dialysis was 1.8 L. The 90-day patient and dialysis-free survival rates were 90% and 99%, respectively. One-year patient survival rates based on the pretransplant renal replacement status and the MELD status were not statistically different. This is the first large study to demonstrate the safety and feasibility of IOHD in a cohort of critically ill patients with high MELD scores undergoing LT with good patient and renal outcomes.

Prevalence of renal dysfunction in patients with cirrhosis according to ADQI-IAC working party proposal

BACKGROUND/AIMS

A revised classification system for renal dysfunction in patients with cirrhosis was proposed by the Acute Dialysis Quality Initiative and the International Ascites Club Working Group in 2011. The aim of this study was to determine the prevalence of renal dysfunction according to the criteria in this proposal.

METHODS

The medical records of cirrhotic patients who were admitted to Konkuk University Hospital between 2006 and 2010 were reviewed retrospectively. The data obtained at first admission were collected. Acute kidney injury (AKI) and chronic kidney disease (CKD) were defined using the proposed diagnostic criteria of kidney dysfunction in cirrhosis.

RESULTS

Six hundred and forty-three patients were admitted, of whom 190 (29.5%), 273 (42.5%), and 180 (28.0%) were Child-Pugh class A, B, and C, respectively. Eighty-three patients (12.9%) were diagnosed with AKI, the most common cause for which was dehydration (30 patients). Three patients had hepatorenal syndrome type 1 and 26 patients had prerenal-type AKI caused by volume deficiency after variceal bleeding. In addition, 22 patients (3.4%) were diagnosed with CKD, 1 patient with hepatorenal syndrome type 2, and 3 patients (0.5%) with AKI on CKD.

CONCLUSIONS

Both AKI and CKD are common among hospitalized cirrhotic patients, and often occur simultaneously (16.8%). The most common type of renal dysfunction was AKI (12.9%). Diagnosis of type 2 hepatorenal syndrome remains difficult. A prospective cohort study is warranted to evaluate the clinical course in cirrhotic patients with renal dysfunction.

Acute Kidney Dysfunction in Patients with Chronic Hepatitis C Virus Infection: Analysis of Viral and Non-viral Factors

BACKGROUND

Multiple studies have shown a relationship between chronic hepatitis C infection and chronic kidney disease. The prevalence, severity, underlying etiologies and predictors of acute kidney dysfunction (AKD) events in patients with hepatitis C has not been studied.

METHODS

We investigated viral and non-viral factors in the development renal dysfunction in 468 HCV patients retrospectively over a period of observation ranging from 3 months to 6 yrs.

RESULTS

A total of 124 AKD events occurred in 63 patients. On regression analysis; gender, race, alcohol abuse, HIV (Human immune deficiency virus) status, body mass index, baseline viral load (HCV-PCR), and genotype did not predict an event of AKD. Decompensated liver disease, history of IVDU, diabetes mellitus and baseline creatinine were independent predictors of AKD.

CONCLUSION

Development of AKD in patient with hepatitis C virus infection is independent of the genotype and viral load at baseline and is mostly predisposed by known prevalent factors in patients with hepatitis C such as diabetes, hypertension and intravenous drug use. Decompensated liver disease is the single most viral-related factor that predisposes for AKD.

[Hepatorenal syndrome]

Hepatorenal syndrome is a severe complication of end-stage liver disease. The pathophysiological hallmark is severe renal vasoconstriction, resulting from peripheral and splanchnic vasodilation as well as activation of renal vasoconstrictor molecules, which induce the effective arterial volume reduction and the functional renal failure. The diagnosis of hepatorenal syndrome is currently based on the exclusion of other causes of renal failure (especially prerenal). Spontaneous bacterial peritonitis is one of the triggering factors and should be sought in all patients with severe liver disease and acute renal failure. Quickly treating patients with parental antibiotics and albumin infusion significantly decreases the risk. The combined use of intravenous albumin, splanchnic and peripheral vasoconstrictor and/or renal replacement therapy sometimes enables a delay until liver transplantation (or combined liver-kidney in selected patients). Transplantation is in fact the only way to improve the long-term prognosis.

Relative bioavailability of tolvaptan administered via nasogastric tube and tolvaptan tablets swallowed intact

PURPOSE

The bioavailability of a crushed tolvaptan tablet suspended in water and administered by nasogastric (NG) tube was compared to the bioavailability from the tablet administered whole.

METHODS

In a randomized crossover study, 28 healthy adults received a single 15-mg dose of tolvaptan on two occasions (one dose given as an intact tablet swallowed whole and the other as a crushed tablet in suspension given by NG tube), with a washout interval of ≥7 days. During each administration period, blood samples were collected at 15 time points over 36 hours. A validated liquid chromatography-tandem mass spectrometry assay was used to obtain plasma tolvaptan concentrations. Plasma tolvaptan time-concentration data were analyzed using noncompartmental methods, and pharmacokinetic data including maximum concentration (Cmax), time to Cmax (tmax), area under the concentration-time curve (AUC) from time zero to the time of the last measurable concentration (AUCt), and AUC extrapolated to infinity (AUC∞) resulting from oral and NG tube tolvaptan delivery were compared via repeated-measures, mixed-effects analysis of variance. Due to differences in total drug exposure seen, an in vitro experiment was conducted on three dose levels to quantify drug sequestration.

RESULTS

The ratios of geometric mean Cmax, AUCt, and AUC∞ values (expressed as a percentage) with NG tube versus oral tolvaptan administration were 88.9%, 74.3%, and 74.2%, respectively; the latter two values were not within the specified bioequivalence tolerance limits (80-125%). In vitro analysis showed that approximately 11% of all tolvaptan doses evaluated was sequestered by the NG tube.

CONCLUSION

In healthy adults, a single 15-mg dose of tolvaptan administered as a crushed tablet suspended in water by NG tube resulted in AUCt and AUC∞ values that were approximately 25% lower than those observed after oral administration of a 15-mg tolvaptan tablet swallowed intact.