Characterization of inflammatory response in hepatorenal syndrome: Relationship with kidney outcome and survival

Hepatorenal Syndrome in Cirrhosis

Hepatorenal syndrome (HRS) is a form of kidney dysfunction that characteristically occurs in liver cirrhosis. It is characterized by a marked impairment of kidney function in response to circulatory and hemodynamic alterations that occur in advanced stages of liver cirrhosis, aggravated by systemic inflammation and bacterial translocation. The classical definitions of the types of HRS have been recently revisited and 2 forms of HRS have been redefined: the acute form, referred to as acute kidney injury (HRS-AKI), and the chronic form, referred to as chronic kidney disease. HRS-AKI is one of the most severe forms of AKI in patients with cirrhosis and it consists of an abrupt impairment of kidney function, frequently triggered by an infection, appearing in the setting of advanced decompensated cirrhosis. Differential diagnosis with other causes of AKI is crucial because HRS-AKI requires a specific treatment. Differential diagnosis with AKI-acute tubular necrosis may be challenging and kidney biomarkers may be useful in this setting. Treatment of HRS-AKI is based on the administration of vasoconstrictor drugs in combination with volume expansion with albumin. Prognosis of HRS-AKI is poor, and the ideal definitive treatment consists of liver transplantation or simultaneous liver-kidney transplantation. HRS-AKI has a big impact on patients' quality of life. Management of HRS-AKI remains challenging in specific situations such as alcohol-associated hepatitis or metabolic-associated steatotic liver disease cirrhosis. Developing preventive measures for HRS-AKI, improving its early identification, discovering new biomarkers for differential diagnosis, and improving the response to therapy are some of the unmet needs in the field of HRS-AKI.

Post Liver Transplant Renal Dysfunction-Evaluation, Management and Immunosuppressive Practice

Liver transplantation (LT) is an effective and lifesaving treatment for patients with end-stage liver disease and hepatocellular carcinoma. Significant improvement in intermediate and long-term survival has been possible due to advancements in immunosuppressive therapy, perioperative care, and surgical techniques. Despite these advances, metabolic complications, including diabetes mellitus, cardiovascular diseases, malignancies, and renal dysfunction, are challenging issues after LT. Acute kidney injury (AKI) and chronic kidney disease (CKD) after LT are common and result in significant morbidity and mortality. Early diagnosis of kidney injury after LT is challenging, and no technique has yet proven effective in prediction of renal dysfunction. The methods for assessing renal function range from formulas that predict glomerular filtration rate to non-invasive biomarkers. The universal adoption of the model for end-stage liver disease has a direct impact on the incidence of peri-transplant AKI and development of CKD in the long-term. Post-LT renal dysfunction is multifactorial and is usually a result of pre-transplantation comorbidities, occurrence of renal dysfunction on the waiting list, perioperative events, and post-transplant nephrotoxic immunosuppressive medication use. Early identification of patients at risk for renal dysfunction and adoption of preventive measures are crucial in the pre-transplant period. No data are currently available to suggest a surgical technique that reliably demonstrates renal protection. Nephroprotective strategies during LT follow accepted surgical practice guidelines, such as maintenance of intravascular volume and mean arterial pressure. The management of kidney disease following LT is challenging, as by the time the serum creatinine is significantly elevated, few interventions impact the course of progression. Early nephroprotective measures are strongly advised and they mostly center on delaying the administration of calcineurin inhibitors (CNIs) during the initial postoperative period, lowering CNI dosage and combining CNI with mycophenolate mofetil and everolimus. The reasons for renal failure following LT, the techniques used to diagnose it, and the therapies designed to preserve renal function both immediately and late after LT are all critically evaluated in this review.

Acute Kidney Injury and Hepatorenal Syndrome in Patients with Cirrhosis

Acute kidney injury (AKI) is common in hospitalized patients with cirrhosis. Hepatorenal syndrome (HRS) is a type of AKI known as HRS-AKI. It is a severe complication of cirrhosis with high morbidity and mortality. While certain vasoconstrictor medications have been shown to improve HRS-AKI, no clear transplant-free survival benefit has been reported with medical therapies. Patients with HRS-AKI should be considered for urgent liver transplantation evaluation. In this review, we discuss the most recent updates on the definition, diagnosis, and management of AKI in cirrhosis, with special a emphasis on HRS.

Hepatorenal Syndrome-Novel Insights into Diagnostics and Treatment

Hepatorenal syndrome (HRS) is a disorder associated with cirrhosis and renal impairment, with portal hypertension as its major underlying cause. Moreover, HRS is the third most common cause of acute kidney injury, thus creating a major public health concern. This review summarizes the available information on the pathophysiological implications of HRS. We discuss pathogenesis associated with HRS. Mechanisms such as dysfunction of the circulatory system, bacterial infection, inflammation, impaired renal autoregulation, circulatory, and others, which have been identified as critical pathways for development of HRS, have become easier to diagnose in recent years. Additionally, relatively recently, renal dysfunction biomarkers have been found indicating renal injury, which are involved in the pathophysiology of HRS. This review also summarizes the available information on the management of HRS, focusing on vasoconstrictive drugs, renal replacement therapy, and liver transplant together with currently being investigated novel therapies. Analyzing new discoveries for the underlying causes of this condition assists the general research to improve understanding of the mechanism of pathophysiology and thus prevention of HRS.

Novel prognostic biomarkers in decompensated cirrhosis: a systematic review and meta-analysis

BACKGROUND

Patients with decompensated cirrhosis experience high mortality rates. Current prognostic scores, including the model for end-stage liver disease (MELD), may underperform in settings other than in those they were initially developed. Novel biomarkers have been proposed to improve prognostication accuracy and even to predict development of complications.

METHODS

We performed a systematic review and meta-analysis on novel urine and blood biomarkers and their ability to predict 90-day mortality in patients with decompensated cirrhosis. Secondary outcomes included 28-day and 1-year mortality, and development of acute-on-chronic liver failure, acute kidney injury and other complications. To overcome differences in units, temporal changes in assays and reporting heterogeneity, we used the ratio of means (RoM) as measure of association for assessing strength in predicting outcomes. An RoM>1 implies that the mean biomarker level is higher in those that develop the outcome than in those that do not.

RESULTS

Of 6629 unique references, 103 were included, reporting on 29 different biomarkers, with a total of 31 362 biomarker patients. Most studies were prospective cohorts of hospitalised patients (median Child-Pugh-Turcotte score of 9 and MELD score of 18). The pooled 90-day mortality rate was 0.27 (95% CI 0.24 to 0.29). The RoM for predicting 90-day mortality was highest for interleukin 6 (IL-6) (2.56, 95% CI 2.39 to 2.74), followed by urinary neutrophil gelatinase-associated lipocalin (uNGAL) (2.42, 95% CI 2.20 to 2.66) and copeptin (2.33, 95% CI 2.17 to 2.50). These RoMs were all higher than for MELD (1.44, 95% CI 1.42 to 1.46).

CONCLUSION

Novel biomarkers, including IL-6, uNGAL and copeptin, can probably improve prognostication of patients with decompensated cirrhosis compared with MELD alone.

Soluble suppression of tumorigenicity 2 is a potential predictor of post-liver transplant renal outcomes

Acute kidney injury is considered an independent prognostic factor for mortality in patients with liver cirrhosis. Non-treated acute kidney injury can progress to hepatorenal syndrome with a poor prognosis. As suppression of tumorigenicity 2 (ST2) is a member of the interleukin-1 receptor family that aggravates inflammation and fibrotic changes in multiple organs, we measured soluble ST2 (sST2) level in the serum and urine of liver-transplant recipients at the time of transplantation. The serum sST2 level significantly increased in liver-transplant recipients with suppressed kidney function compared with that in recipients with normal function. In recipients with severely decreased liver function (model for end-stage liver disease score ≥ 30), the serum sST2 level was higher than that in recipients with preserved liver function (model for end-stage liver disease score ≤ 20, P = 0.028). The serum sST2 level in recipients with hepatorenal syndrome was higher than that in liver-transplant recipients without hepatorenal syndrome (P = 0.003). The serum sST2 level in patients with hepatorenal syndrome was higher than that in recipients without a history of acute kidney injury (P = 0.004). Recipients with hepatorenal syndrome and recovered kidney function showed higher sST2 levels than those who did not recover (P = 0.034). Collectively, an increase in the serum sST2 level reflects a decrease in both kidney and liver functions. Thus, measuring sST2 level at the time of liver transplantation can help predict renal outcomes.

Hepatorenal syndrome: Current concepts and future perspectives

Hepatorenal syndrome (HRS), a progressive but potentially reversible deterioration of kidney function, remains a major complication in patients with advanced cirrhosis, often leading to death before liver transplantation (LT). Recent updates in the pathophysiology, definition, and classification of HRS have led to a complete revision of the nomenclature and diagnostic criteria for HRS type 1, which was renamed HRS-acute kidney injury (AKI). HRS is characterized by severe impairment of kidney function due to increased splanchnic blood flow, activation of several vasoconstriction factors, severe vasoconstriction of the renal arteries in the absence of kidney histologic abnormalities, nitric oxide dysfunction, and systemic inflammation. Diagnosis of HRS remains a challenge because of the lack of specific diagnostic biomarkers that accurately distinguishes structural from functional AKI, and mainly involves the differential diagnosis from other forms of AKI, particularly acute tubular necrosis. The optimal treatment of HRS is LT. While awaiting LT, treatment options include vasoconstrictor drugs to counteract splanchnic arterial vasodilation and plasma volume expansion by intravenous albumin infusion. In patients with HRS unresponsive to pharmacological treatment and with conventional indications for kidney replacement therapy (KRT), such as volume overload, uremia, or electrolyte imbalances, KRT may be applied as a bridging therapy to transplantation. Other interventions, such as transjugular intrahepatic portosystemic shunt, and artificial liver support systems have a very limited role in improving outcomes in HRS. Although recently developed novel therapies have potential to improve outcomes of patients with HRS, further studies are warranted to validate the efficacy of these novel agents.

Pathophysiology of Hepatorenal Syndrome - Acute Kidney Injury

Hepatorenal syndrome is a complication of liver cirrhosis with ascites that results from the complex interplay of many pathogenetic mechanisms. Advanced cirrhosis is characterized by the development of hemodynamic changes of splanchnic and systemic arterial vasodilatation, with paradoxical renal vasoconstriction and renal hypoperfusion. Cirrhosis is also an inflammatory state. The inflammatory cascade is initiated by a portal hypertension-induced increased translocation of bacteria, bacterial products, and endotoxins from the gut to the splanchnic and then to the systemic circulation. The inflammation, whether sterile or related to infection, is responsible for renal microcirculatory dysfunction, microthrombi formation, renal tubular oxidative stress, and tubular damage. Of course, many of the bacterial products also have vasodilatory properties, potentially exaggerating the state of vasodilatation and worsening the hemodynamic instability in these patients. The presence of cardiac dysfunction, related to cirrhotic cardiomyopathy, with its associated systolic incompetence, can aggravate the mismatch between the circulatory capacitance and the circulation volume, worsening the extent of the effective arterial underfilling, with lower renal perfusion pressure, contributing to renal hypoperfusion and increasing the risk for development of acute kidney injury. The presence of tense ascites can exert an intra-abdominal compartmental syndrome effect on the renal circulation, causing renal congestion and hampering glomerular filtration. Other contributing factors to renal dysfunction include the tubular damaging effects of cholestasis and adrenal dysfunction. Future developments include the use of metabolomics to identify metabolic pathways that can lead to the development of renal dysfunction, with the potential of identifying biomarkers for early diagnosis of renal dysfunction and the development of treatment strategies.

Renal damage in Hepatorenal Syndrome: A still unsolved issue

Acute kidney injury (AKI) is a common complication of cirrhosis, burdened by high morbidity and mortality rates and progression to chronic kidney disease. Hepatorenal syndrome (HRS) is a peculiar type of functional AKI observed in cirrhotic patients with ascites. HRS diagnosis is still clinical, once pre-renal azotemia and intrinsic kidney damage have been excluded by applying well-established and internationally adopted criteria. HRS is considered reversible because of the absence of intrinsic renal damage. However, HRS reversibility has been questioned, due to the lack of response to treatment with vasoconstrictors plus albumin in a relevant percentage of patients and to the persistence of renal dysfunction in HRS patients who underwent liver transplantation (LT). Indeed, LT is the only ultimate treatment, as it solves both liver failure and portal hypertension. Thus, the presence of renal damage in HRS can be hypothesized. In this scenario, neutrophil gelatinase-associated lipocalin (NGAL), one of the most promising biomarkers, may help in characterizing the type of renal injury, distinguishing between HRS and acute tubular necrosis. This review gathers the available evidence in favor and against the presence of structural lesions in HRS in terms of either renal histology and urinary biomarkers with a particular focus on NGAL. The ability to properly characterize which component of renal dysfunction prevails - functional rather than structural - entails a relevant clinical impact for the treatment of these patients, both in terms of medical therapy and liver vs. combined liver-kidney transplantation.

The progression of hepatorenal syndrome-acute kidney injury in acute alcohol-associated hepatitis: renal outcomes after liver transplant

Background

Hepatorenal syndrome-acute kidney injury (HRS-AKI) is a complication of advanced liver disease in patients with ascites and circulatory dysfunction. Little data remain on the relationship between HRS-AKI outcomes and different etiologies of liver disease post-liver transplant (LT).

Objectives

The primary aim was to evaluate the effect of HRS-AKI on renal outcomes in patients with acute alcohol-associated hepatitis (AAH) compared to chronic liver disease (CLD) after LT. The secondary aim was to evaluate the impact of acuity and chronicity of alcohol-associated liver disease in patients with HRS-AKI post-LT renal outcomes.

Design

A retrospective observational study of patients undergoing urgent inpatient liver transplant evaluation (LTE) for cirrhosis and AAH at single academic LT center between October 2017 and July 2021 was conducted.

Methods

Patients with HRS-AKI were selected based on indication for LTE: acute AAHHRS or CLDHRS. CLDHRS was categorized by disease etiology: cirrhosis due to alcohol (A-CLDHRS) versus cirrhosis from other causes (O-CLDHRS). CLD patients without HRS-AKI were labeled CLDno HRS.

Results

A total of 210 subjects underwent LTE; 25% were evaluated for AAH and 75% were evaluated for CLD. Hepatorenal syndrome was more common in subjects evaluated for AAH (37/47) than CLD (104/163) (78.7 versus 63.8%, p = 0.04). For the primary outcome, AAHHRS subjects required ⩾30 days post-LT renal replacement therapy (RRT) more often than subjects with CLDHRS (p = 0.02) and CLDno HRS (p < 0.01). There was no significant difference in other forms of long-term renal outcomes including kidney transplant referral and kidney transplant among cohorts. In subgroup analysis, 30-days post-LT RRT was more common in AAHHRS than in A-CLDHRS (p = 0.08). Logistic regression showed that AAHHRS conferred a 20× and 3.3× odds of requiring ⩾30 days post-LT RRT compared to CLDno HRS and CLDHRS, respectively. Postoperative complications were similar across cohorts, but had a significant effect on 30-day renal outcome post-LT.

Conclusions

Patients with AAH were more likely to develop HRS and require RRT pre- and post-LT at our center. The etiology of hepatic decompensation and postoperative complications affect renal recovery post-LT. The systemic inflammation of AAH in addition to conditions favoring renal hypoperfusion may contribute to the unfavorable outcomes of HRS-AKI after LT in this patient population.

Kidney disease in patients with chronic liver disease: Does sex matter?

Kidney disease in patients with liver disease is serious and increases mortality. Up to 50% of patients hospitalized experience an episode of acute kidney injury. In general, men with liver disease are thought to be at increased risk of kidney disease. However, this association should be considered with caution because most studies use creatinine-based inclusion criteria, which is negatively biased against women. In this review, we synthesize data on sex differences in kidney disease in patients with chronic liver disease in the clinical setting and discuss potential physiologic underpinnings.

Clinical and pathophysiological understanding of the hepatorenal syndrome: Still wrong or still not exactly right?

The hepatorenal syndrome (HRS) is one major extrahepatic complication of end-stage liver diseases. While circulatory dysregulation is considered as primary etiology for HRS, cirrhosis-related (systemic) inflammation and/or cardial dysfunction may also play a key pathogenic role in HRS development. Exclusion of other causes of acute kidney injury (AKI) is required for diagnosis of HRS-AKI by the definition of the International Club of Ascites. However, the pathophysiology of HRS is not understood completely and there are still limited therapeutic options. Reversibility of renal dysfunction after liver transplantation indicates that HRS-AKI is a functional disorder caused by altered cellular function. The interplay between systemic inflammation and the onset of kidney-related hypometabolism may have a key role and needs to be studied in depth. This minireview challenges simplified views of the HRS in the context of diagnostics and therapy stressing the need for further evidence to advance the knowledge on this syndrome.

Review article: diagnosis, pathophysiology and management of atrial fibrillation in cirrhosis and portal hypertension

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia and its management in cirrhosis can be challenging due to the altered hepatic metabolism of medications and increased risk of bleeding.

AIMS

To provide a comprehensive overview of the diagnosis, pathophysiology and management of AF in patients with cirrhosis from both a cardiology and a hepatology perspective.

METHODS

An extensive literature search was performed using the terms 'atrial fibrillation' and 'cirrhosis'. Guideline documents and consensus statements were explored.

RESULTS

The prevalence of AF in patients with cirrhosis ranges between 6.6% and 14.2%, while the incidence of new-onset AF in the post-operative period after liver transplant ranged between 6.8% and 10.2%. AF in patients with cirrhosis is associated with adverse outcomes in both pre-transplant and post-transplant settings, including an increased risk of stroke when compared to the general population. We review the pathogenesis of AF in general and in cirrhosis. This review also provides guidance on the management of AF, including the use of anticoagulation and rate versus rhythm control. In the absence of strict contraindications, all patients with cirrhosis and AF should be anticoagulated. The use of DOACs is preferred over vitamin K antagonists. In patients with a high bleeding risk, a DOAC with an approved antidote may be preferred.

CONCLUSIONS

Atrial fibrillation is increased in patients with cirrhosis. AF management requires careful consideration of treatment options. Since patients with cirrhosis were excluded from all major randomised clinical trials, dedicated research on the pathophysiology and management of AF in cirrhosis is needed.

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.

Establishment and evaluation of an early prediction model of hepatorenal syndrome in patients with decompensated hepatitis B cirrhosis

BACKGROUND AND AIM

In China, hepatorenal syndrome is a serious complication in the decompensated stage of hepatitis B cirrhosis, which requires early clinical intervention, so the early diagnosis of hepatorenal syndrome is crucial. This study establishes a new predictive model based on serum biomarkers for the early diagnosis of hepatorenal syndrome.

METHODS

Patients with decompensated hepatitis B cirrhosis who met the inclusion and exclusion criteria were retrospectively enrolled. Patients were randomly assigned to the training dataset and validation dataset at a 7:3 ratio. Univariate and multivariate logistic regression analyses were used to screen the risk factors for hepatorenal syndrome. The identified risk factors were used to establish and verify a model.

RESULTS

This study included 255 patients with decompensated hepatitis B cirrhosis, including 184 in the training group and 71 in the validation group. The multivariate logistic regression model was established in the training group and verified in the validation group. Logistic regression showed that hemoglobin (OR 0.938, 95% CI 0.908-0.969), total bilirubin (OR 1.014, 95% CI 1.008-1.021) and creatinine (OR 1.079, 95% CI 1.043-1.117) were independent risk factors for hepatorenal syndrome (P < 0.05). These were used to establish the model. In the training group and the validation group, the area under the ROC curve of the nomogram for the diagnosis of hepatorenal syndrome was 0.968 and 0.980, respectively.

CONCLUSION

The three serum biomarkers, including hemoglobin, total bilirubin and creatinine, can be used as independent early predictors of hepatorenal syndrome in patients with decompensated hepatitis B cirrhosis.

Elevated D-Dimer levels correlate with the development of hepatorenal syndrome and a poor outcome in patients with cirrhosis

OBJECTIVES

Whether hemostatic status was correlated with the diverse types of acute kidney injury in cirrhotic patients is unclear. The present study aimed to investigate the relationship between hemostatic markers and the diverse types of acute kidney injury (AKI) in liver cirrhosis.

PATIENTS AND METHODS

Cirrhotic patients with consecutive treatment at the First Affiliated Hospital of Medicine School, Zhejiang University, were pooled in a cohort. Their demographic and clinical data, biochemistry parameters and hemostatic markers were assessed to identify risk factors for the development and prognosis of AKI.

RESULTS

A total of 773 cirrhotic patients were included in this cohort. Patients with hepatorenal syndrome (HRS) had significantly higher D-Dimer than those with the other types of AKI. In univariate COX regression, APTT, TT, INR, D-Dimer and Fib were correlated with the development of AKI, HRS and acute tubular necrosis (ATN), however, only D-Dimer remained independently associated with the development of AKI and HRS in multivariate COX regression. The area under the ROC curve of D-Dimer was 0.755 (95%CI, 0.718-0.793) in predicting the development of AKI, 0.879 (95%CI, 0.791-0.967) in predicting the development of HRS, respectively. D-Dimer was used for diagnosis of HRS with a sensitivity of 87.3% and specificity of 72.9% at the cutoff of 3.7 (mg/L FEU). Survival rates differed significantly between groups by D-Dimer level.

CONCLUSIONS

Hemostatic markers were significantly associated with the diverse types of AKI. D-Dimer was an independent risk factor for HRS and correlated with a poor outcome in cirrhotic patients.

AGA Clinical Practice Update on the Evaluation and Management of Acute Kidney Injury in Patients With Cirrhosis: Expert Review

DESCRIPTION

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update is to review the available published evidence and expert advice regarding the clinical management of patients with suspected acute kidney injury in patients with cirrhosis.

METHODS

This article provides practical advice for the management of patients with cirrhosis and acute kidney injury based on the best available published evidence. This best practice document is not based on a formal systematic review. This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through the standard procedures of Clinical Gastroenterology & Hepatology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Since systematic reviews were not performed, these BPA statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: Acute kidney injury (AKI) should be diagnosed when the serum creatinine increases by ≥0.3 mg/dL within 48 hours or is ≥50% from baseline or when the urine output is reduced below 0.5 mL/kg/h for >6 hours. BEST PRACTICE ADVICE 2: Preventive measures against the development of AKI in cirrhosis include (1) avoidance of potentially nephrotoxic medications like nonsteroidal anti-inflammatory drugs (NSAIDs), (2) avoidance of excessive or unmonitored diuretics or nonselective beta-blockade, (3) avoidance of large-volume paracentesis without albumin replacement, and (4) counseling patients to avoid alcohol use. BEST PRACTICE ADVICE 3: (A) Investigation is directed to determining the cause of AKI, which can be due to hypovolemic causes (volume responsive, and the most common cause of AKI in patients with cirrhosis); acute tubular necrosis; hepatorenal syndrome with AKI (HRS-AKI) (a functional renal failure that persists despite volume repletion); HRS with acute kidney disease, a type of functional renal failure of <3 months- duration in which criteria for HRS-AKI are not met; or postrenal, which occurs only rarely. (B) The specific type of AKI should be identified through a careful history, physical examination, blood biochemistry, urine microscopic examination, urine chemistry (Na+ and urea) and selected urinary biomarkers, and renal ultrasound. BEST PRACTICE ADVICE 4: A rigorous search for infection is required in all patients with AKI. A diagnostic paracentesis should be carried out to evaluate for spontaneous bacterial peritonitis; blood and urine cultures and chest radiograph are also required. There is no role for routine prophylactic antibiotics in patients with AKI, but broad-spectrum antibiotics should be started whenever infection is strongly suspected. BEST PRACTICE ADVICE 5: When AKI is diagnosed, diuretics and nonselective beta-blockers should be held, NSAIDs discontinued, the precipitating cause of AKI treated, and fluid losses replaced, administering albumin 1 g/kg/d for 2 days if the serum creatinine shows doubling from baseline. Urine output, vital signs, and when indicated, echocardiography or CVP (if there is a pre-existing central line) should be used to monitor fluid status. BEST PRACTICE ADVICE 6: When the serum creatinine remains higher than twice the baseline value despite these measures, treatment of HRS-AKI should be initiated with albumin at a dose of 1 g/kg intravenously on day 1 followed by 20-40 g daily along with vasoactive agents (terlipressin; if terlipressin is not available, either a combination of octreotide and midodrine; or norepinephrine, depending on institutional preferences) and continued either until 24 hours following the return of the serum creatinine level to within ≤0.3 mg/dL of baseline for 2 consecutive days or for a total of 14 days of therapy. BEST PRACTICE ADVICE 7: Terlipressin should be initiated as a bolus dose of 1 mg every 4-6 hours (total 4-6 mg/d). The dose should be increased to a maximum of 2 mg every 4-6 hours (total 8-12 mg/d) if there is no reduction in serum creatinine at day 3 of therapy by at least 25% compared to the baseline value. Alternatively, clinicians can administer terlipressin by continuous intravenous infusion at a lower starting dose of 2 mg/d, which may reduce ischemic side effects and increase the dose gradually every 24-48 hours up to a maximum dose of 12 mg/d, or reversal of HRS. As per Food and Drug Administration restrictions, terlipressin should not be used in patients with a serum creatinine ≥5 mg/dL, or oxygen saturation of <90%. BEST PRACTICE ADVICE 8: Oral midodrine when used should be initiated at doses of 7.5 mg and titrated upward to 12.5 mg 3 times daily with octreotide (starting with 100 μg and titrating upward to 200 μg subcutaneously 3 times daily). BEST PRACTICE ADVICE 9: Norepinephrine should be used as a continuous intravenous infusion at a starting dose of 0.5 mg/h and the dose increased every 4 hours by 0.5 mg/h to a maximum of 3 mg/h with the goal of increasing the mean arterial pressure by ≥10 mm Hg and/or the urine output to >50 mL/h for at least 4 hours. BEST PRACTICE ADVICE 10: The risks of ischemic side effects of terlipressin and norepinephrine include angina and ischemia of fingers, skin, and intestine. These side effects may be lowered by starting at the lowest dose and gradually titrating upward. BEST PRACTICE ADVICE 11: Fluid status should be closely monitored because of the risk of pulmonary edema with excessive use of albumin. BEST PRACTICE ADVICE 12: Renal replacement therapy (RRT) may be used in the management of (A) AKI secondary to acute tubular necrosis; (B) HRS-AKI in potential candidates for liver transplantation (that is, RRT should not be used in patients with HRS-AKI who are not candidates for liver transplantation); and (C) AKI of uncertain etiology in which the need for RRT may be considered on an individual basis. BEST PRACTICE ADVICE 13: Transjugular intrahepatic portosystemic shunts should not be used as a specific treatment of HRS-AKI. BEST PRACTICE ADVICE 14: Liver transplantation is the most effective treatment for HRS-AKI. Pharmacotherapy for HRS-AKI before proceeding with liver transplantation may be associated with better post-liver transplantation outcomes. Selected patients with HRS-AKI may require simultaneous liver kidney transplantation based on updated Organ Procurement and Transplantation Network listing criteria.

The urine albumin creatinine ratio is one of the predictors of acute kidney injury in hepatitis C-related cirrhotic hepatic encephalopathy

Background/objective

Hepatic encephalopathy (HE) is a main manifestation of acute decompensation in liver cirrhosis. Recently, systemic inflammation was proposed as a key mechanism in the development of acute kidney injury (AKI) in cirrhotic patients. The urine albumin creatinine ratio (UACR) is considered a marker of systemic inflammation in a variety of clinical settings. Here, we aimed to evaluate the role of the urine albumin creatinine ratio in the early prediction of AKI in HE.

Patients and methods

Sixty-seven consecutive patients presented with cirrhotic HE, and 59 age- and sex-matched cirrhotic patients with no history of HE served as controls. HE was defined and graded by the West Haven criteria. The severity of liver cirrhosis was evaluated by the Child-Turcotte-Pugh (CTP) score, and model for end-stage liver disease (MELD) score. The incidence of AKI that developed during hospital admission and the in-hospital mortality rate was estimated among HE patients. In addition, predictors of AKI were analyzed.

Results

The mean age of HE patients was 58.09±12.26 years; 36 (53.7%) were males, and 31 (46.3%) were females. Among HE patients, 16 (23.9%) developed AKI during hospital admission. The in-hospital mortality rate among HE patients was 22 (32.8%), the in-hospital mortality among HE-AKI patients was 81.3% (n=13/16), and UACR levels > 91.5 mg/g identified HE-AKI with 81.25% sensitivity (AUC = 0.85, P ≤ 0.001).

Conclusions

Patients with cirrhotic HE are at high risk of AKI. HE-AKI patients had a high rate of in-hospital mortality. Estimation of UACR at hospital admission is suggested for the early detection of patients with HE-AKI.

Patterns of kidney dysfunction in acute-on-chronic liver failure: Relationship with kidney and patients' outcome

Impairment of kidney function is common in acute-on-chronic liver failure (ACLF). Patterns of kidney dysfunction and their impact on kidney and patient outcomes are ill-defined. Aims of the current study were to investigate patterns of kidney dysfunction and their impact on kidney and patient outcomes in patients with acute decompensation (AD) of cirrhosis, with or without ACLF. This prospective study includes 639 admissions for AD (232 with ACLF; 407 without) in 518 patients. Data were collected at admission and during hospitalization, and patients were followed up for 3 months. Urine samples were analyzed for kidney biomarkers. Most patients with ACLF (92%) had associated acute kidney injury (AKI), in most cases without previous chronic kidney disease (CKD), whereas some had AKI-on-CKD (70% and 22%, respectively). Prevalence of AKI in patients without ACLF was 35% (p < 0.001 vs. ACLF). Frequency of CKD alone was low and similar in both groups (4% and 3%, respectively); only a few patients with ACLF (4%) had no kidney dysfunction. AKI in ACLF was associated with poor kidney and patient outcomes compared with no ACLF (AKI resolution: 54% vs. 89%; 3-month survival: 51% vs. 86%, respectively; p < 0.001 for both). Independent predictive factors of 3-month survival were Model for End-Stage Liver Disease-Sodium score, ACLF status, and urine neutrophil gelatinase-associated lipocalin (NGAL). AKI is almost universal in patients with ACLF, sometimes associated with CKD, whereas CKD alone is uncommon. Prognosis of AKI depends on ACLF status. AKI without ACLF has good prognosis. Best predictors of 3-month survival are MELD-Na, ACLF status, and urine NGAL.

Transjugular intrahepatic porto-systemic shunt in cirrhotic patients with hepatorenal syndrome - chronic kidney disease: Impact on renal function

BACKGROUND AND AIMS

Transjugular intrahepatic porto-systemic shunt (TIPS) ameliorates renal function in type-2 hepatorenal syndrome (HRS). Available evidence is based on 'old' HRS diagnostic criteria, and not on the current definition of HRS - chronic kidney disease (HRS-CKD). Among patients who underwent TIPS for refractory ascites over the last 12 years, we investigated clinical and renal function evolution of those with HRS-CKD.

METHODS

among 212 patients, 41 with HRS-CKD were included. Renal function was evaluated for 12 months after TIPS, along with management of ascites and transplant-free survival (TFS).

RESULTS

renal function significantly improved already one week after TIPS [serum creatinine (sCr): 1.37 ± 0.23 vs 1.94 ± 0.54 mg/dl, p< 0.001]; the amelioration was maintained during the whole follow-up and was observed in every CKD stage, defined according to baseline estimated Glomerular Filtration Rate (eGFR). sCr and eGFR became comparable between different CKD stages after only one week, whilst significantly different at baseline. TIPS led to a remarkable improvement in the control of ascites in all CKD stages and no significant differences in TFS were recorded.

CONCLUSIONS

TIPS led to an early, substantial and persistent improvement in renal function in patients with HRS-CKD, irrespective of their baseline CKD stage.

Management of hepatorenal syndrome in liver cirrhosis: a recent update

Hepatorenal syndrome (HRS) is a serious form of renal dysfunction in patients with cirrhosis and ascites. It is an important component of the acute-on-chronic liver failure (ACLF) syndrome. Significant recent changes in the understanding of the pathophysiology of renal dysfunction in cirrhosis include the role of inflammation in addition to hemodynamic changes. The term acute kidney injury (AKI) is now adopted to include all functional and structural forms of acute renal dysfunction in cirrhosis, with various stages describing the severity of the condition. Type 1 hepatorenal syndrome (HRS1) is renamed HRS-AKI, which is stage 2 AKI [doubling of baseline serum creatinine (sCr)] while fulfilling all other criteria of HRS1. Albumin is used for its volume expanding and anti-inflammatory properties to confirm the diagnosis of HRS-AKI. Vasoconstrictors are added to albumin as pharmacotherapy to improve the hemodynamics. Terlipressin, although not yet available in North America, is the most common vasoconstrictor used worldwide. Patients with high grade of ACLF treated with terlipressin are at risk for respiratory failure if there is pretreatment respiratory compromise. Norepinephrine is equally effective as terlipressin in reversing HRS1. Recent data show that norepinephrine may be administered outside the intensive care setting, but close monitoring is still required. There has been no improvement in overall or transplant-free survival shown with vasoconstrictor use, but response to vasoconstrictors with reduction in sCr is associated with improvement in survival. Non-responders to vasoconstrictor plus albumin will need liver transplantation as definite treatment with renal replacement therapy as a bridge therapy. Combined liver and kidney transplantation is recommended for patients with prolonged history of AKI, underlying chronic kidney disease or with hereditary renal conditions. Future developments, such as the use of biomarkers and metabolomics, may help to identify at risk patients with earlier diagnosis to allow for earlier treatment with improved outcomes.

The Effect of Artificial Liver Support System on Prognosis of HBV-Derived Hepatorenal Syndrome: A Retrospective Cohort Study

Hepatorenal syndrome (HRS) could occur when patients get decompensated liver cirrhosis. Meanwhile, hepatitis B virus (HBV) infection raises the risk of mortality of the end-stage liver diseases. As the artificial liver support system (ALSS) has been applied in liver failure, whether ALSS could benefit HBV-derived HRS remains uncertain. We retrospectively enlisted eligible HRS patients and compared the baseline characteristics and prognosis between HBV-derived HRS and non-HBV-derived HRS. Furthermore, propensity score matching (PSM) and Cox regression analyses were used to assess the beneficial effect of ALSS on HBV-derived HRS. In addition, a stratified analysis was carried out according to the degree of acute kidney injury (AKI) and the number of organ failures to observe in which populations ALSS can obtain the most excellent therapeutic effect. 669 patients were diagnosed as HRS, including 298 HBV negative and 371 HBV positive. Baseline characteristics were different between patients with HBV positive and HBV negative. HBV-derived HRS has higher 28-day mortality, though without a statistical difference. After PSM, 50 patients treated with ALSS and 150 patients treated with standard medical treatment (SMT) constituted a new cohort for the following analysis. We found that ALSS could significantly benefit HRS patients (P = 0.025). Moreover, the median survival time of patients treated with ALSS was longer than those treated with SMT. INR, neutrophil percentage, and treatment with ALSS were independent predictive factors for short-term mortality in HBV-derived HRS. The stratified analysis showed that ALSS could reduce the 28-day mortality of patients with HBV-derived HRS, especially those in AKI stage 3 and with organ failure ≥ 2. Additionally, serum bilirubin was significantly lower after ALSS, and the alteration of INR and creatinine were independent predictive elements for the mortality of HBV-derived HRS. HBV-derived HRS is more severe than non-HBV-derived HRS and has a worse prognosis. ALSS could reduce the short-term mortality of patients with HBV-derived HRS, especially those in AKI stage 3 and with organ failure ≥ 2. INR and the change of creatinine and INR could predict the prognosis of HBV-derived HRS. ChiCTR2200060123.

Perfusion Analysis of Kidney Injury in Rats With Cirrhosis Induced by Common Bile Duct Ligation Using Arterial Spin Labeling MRI

BACKGROUND

Arterial spin labeling (ASL) has been proven to be effective in ischemia-induced acute kidney injury (AKI); however, validation of ASL magnetic resonance imaging (MRI) is limited in AKI in the presence of cirrhosis.

PURPOSE

To investigate the feasibility of ASL in revealing renal blood flow (RBF) changes in kidney injury in the presence of cirrhosis and to assess its value in the early diagnosis of disease.

STUDY TYPE

Longitudinal.

ANIMAL MODEL

Rats were randomized into baseline group (N = 3), sham surgery group (N = 18), and common bile duct ligation (BDL) group (N = 48). All groups were divided into six subgroups based on different sacrificed time points.

FIELD STRENGTH/SEQUENCE

3 T scanner, prototypic pulsed ASL sequence using flow-sensitive alternating inversion recovery preparation, half-Fourier acquisition single-shot turbo spin echo sequence.

ASSESSMENT

RBF measurement was performed by ASL. Hematoxylin-eosin (HE) score, Hypoxia-inducible factor-1alpha (HIF-1α) score, peritubular capillar (PTC) density, alanine aminotransferase, aspartate aminotransferase, serum total bilirubin, total bile acids, serum creatinine (Scr), and blood urea nitrogen (BUN) were harvested.

STATISTICAL TESTS

Analysis of variance, Pearson's correlation coefficient, and receiver operating characteristic curves were performed. P < 0.05 was considered statistically significant.

RESULTS

RBF, HE score, HIF-1α score, and PTC density after BDL were significantly different from baseline. RBF was highly correlated with HE score, HIF-1α score, and PTC density (r = -0.7598, r = -0.7434, r = 0.6406, respectively). RBF and Scr began to differ significantly from baseline at day 3 and 7 after intervention, respectively. The areas under the curves of RBF, Scr, and BUN for distinguishing non-AKI from AKI in cirrhosis were 1.00, 0.888, and 0.911, while those for distinguishing mild from severe kidney injury were 0.961, 0.830, and 0.857, respectively.

DATA CONCLUSION

ASL allows the longitudinal assessment of the degree of AKI induced by cholestatic cirrhosis in rats and can serve as a noninvasive marker for the early and accurate diagnosis of AKI.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 2.

Hepatorenal Syndrome: Pathophysiology

Hepatorenal syndrome (HRS) is defined as a functional renal failure without major histologic changes in individuals with severe liver disease and it is associated with a high mortality rate. Renal hypoperfusion due to marked vasoconstriction as a result of complex circulatory dysfunction has been suggested to be the cornerstone of HRS. Splanchnic and peripheral arterial vasodilation and cirrhotic cardiomyopathy result in effective arterial hypovolemia and compensatory activation of vasoconstrictor mechanisms. The efficacy of current therapeutic strategies targeting this circulatory dysfunction is limited. Increasing evidence suggests a substantial role of systemic inflammation in HRS via either vascular or direct renal effects. Here we summarize the current understanding of HRS pathophysiology.

Impact of liver cirrhosis on ST-elevation myocardial infarction related shock and interventional management, a nationwide analysis

BACKGROUND

Critical care is rapidly evolving with significant innovations to decrease hospital stays and costs. To our knowledge, there is limited data on factors that affect the length of stay and hospital charges in cirrhotic patients who present with ST-elevation myocardial infarction-related cardiogenic shock (SRCS).

AIM

To identify the factors that increase inpatient mortality, length of stay, and total hospital charges in patients with liver cirrhosis (LC) compared to those without LC.

METHODS

This study includes all adults over 18 from the National Inpatient Sample 2017 database. The study consists of two groups of patients, including SRCS with LC and without LC. Inpatient mortality, length of stay, and total hospital charges are the primary outcomes between the two groups. We used STATA 16 to perform statistical analysis. The Pearson's chi-square test compares the categorical variables. Propensity-matched scoring with univariate and multivariate logistic regression generated the odds ratios for inpatient mortality, length of stay, and resource utilization.

RESULTS

This study includes a total of 35798453 weighted hospitalized patients from the 2017 National Inpatient Sample. The two groups are SRCS without LC (n = 758809) and SRCS with LC (n = 11920). The majority of patients were Caucasian in both groups (67% vs 72%). The mean number of patients insured with Medicare was lower in the LC group (60% vs 56%) compared to the other group, and those who had at least three or more comorbidities (53% vs 90%) were significantly higher in the LC group compared to the non-LC group. Inpatient mortality was also considerably higher in the LC group (28.7% vs 10.63%). Length of Stay (LOS) is longer in the LC group compared to the non-LC group (9 vs 5.6). Similarly, total hospital charges are higher in patients with LC ($147407.80 vs $113069.10, P ≤ 0.05). Inpatient mortality is lower in the early percutaneous coronary intervention (PCI) group (OR: 0.79 < 0.11), however, it is not statistically significant. Both early Impella (OR: 1.73 < 0.05) and early extracorporeal membrane oxygenation (ECMO) (OR: 3.10 P < 0.05) in the LC group were associated with increased mortality. Early PCI (-2.57 P < 0.05) and Impella (-3.25 P < 0.05) were also both associated with shorter LOS compared to those who did not. Early ECMO does not impact the LOS; however, it does increase total hospital charge (addition of $24717.85, P < 0.05).

CONCLUSION

LC is associated with a significantly increased inpatient mortality, length of stay, and total hospital charges in patients who develop SRCS. Rural and Non-teaching hospitals have significantly increased odds of extended hospital stays and higher adjusted total hospital charges. The Association of LC with worse outcomes outlines the essential need to monitor these patients closely and treat them early on with higher acuity care. Patients with early PCI had both shorter LOS and reduced inpatient mortality, while early Impella was associated with increased mortality and shorter LOS. Early ECMO is associated with increased mortality and higher total hospital charges. This finding should affect the decision to follow through with interventional management in this cohort of patients as it is associated with poor outcomes and immense resource utilization.

Current aspects of renal dysfunction after liver transplantation

The development of chronic kidney disease (CKD) after liver transplantation (LT) exerts a severe effect on the survival of patients. The widespread adoption of the model for end-stage liver disease score strongly impacted CKD incidence after the procedure, as several patients are transplanted with previously deteriorated renal function. Due to its multifactorial nature, encompassing pre-transplantation conditions, perioperative events, and nephrotoxic immunosuppressor therapies, the accurate identification of patients under risk of renal disease, and the implementation of preventive approaches, are extremely important. Methods for the evaluation of renal function in this setting range from formulas that estimate the glomerular filtration rate, to non-invasive markers, although no option has yet proved efficient in early detection of kidney injury. Considering the nephrotoxicity of calcineurin inhibitors (CNI) as a factor of utmost importance after LT, early nephroprotective strategies are highly recommended. They are based mainly on delaying the application of CNI during the immediate postoperative-period, reducing their dosage, and associating them with other less nephrotoxic drugs, such as mycophenolate mofetil and everolimus. This review provides a critical assessment of the causes of renal dysfunction after LT, the methods of its evaluation, and the interventions aimed at preserving renal function early and belatedly after LT.

Urinary L-FABP is a promising prognostic biomarker of ACLF and mortality in patients with decompensated cirrhosis

BACKGROUND & AIMS

Decompensated cirrhosis (DC) is associated with high mortality, mainly owing to the development of acute-on-chronic liver failure (ACLF). Identifying the patients with DC who are at high risk of mortality and ACLF development is an unmet clinical need. Liver fatty acid-binding protein (L-FABP) is expressed in several organs and correlates with liver and systemic inflammation. Herein, we aimed to assess the prognostic value of L-FABP in patients with DC.

METHODS

A prospective series of 444 patients hospitalized for DC was divided into 2 cohorts: study cohort (305 patients) and validation cohort (139 patients). L-FABP was measured in urine and plasma samples collected at admission. Neutrophil gelatinase-associated lipocalin (NGAL) was also measured in urine samples for comparison.

RESULTS

Urine but not plasma L-FABP correlated with 3-month survival on univariate analysis. On multivariate analysis, urine L-FABP and model for end-stage liver disease (MELD)-Na were the only independent predictors of prognosis. Urine L-FABP levels were higher in patients with ACLF than in those without and also predicted the development of ACLF, together with MELD-Na, during follow-up. In patients with ACLF, urine L-FABP correlated with liver, coagulation, and circulatory failure. Urine L-FABP levels were also increased in patients with acute kidney injury, particularly in those with acute tubular necrosis. The ability of urinary L-FABP to predict survival and ACLF development was confirmed in the validation cohort. Urine NGAL predicted outcome on univariate but not multivariate analysis.

CONCLUSIONS

Urinary L-FABP levels are independently associated with the 3-month clinical course in patients with DC, in terms of mortality and ACLF development. Urinary L-FABP is a promising prognostic biomarker for patients with DC.

LAY SUMMARY

Increased levels of liver fatty acid-binding protein (L-FABP), a protein related to lipid metabolism, have been associated with liver-related diseases. The present study analyzed urinary L-FABP levels in 2 independent groups of patients with decompensated cirrhosis and showed that higher urinary L-FABP levels correlated with increased mortality and risk of acute-on-chronic liver failure development. Therefore, urinary L-FABP levels could be useful as a new tool to predict complications in patients with decompensated cirrhosis.

Hepatorenal syndrome in acute-on-chronic liver failure with acute kidney injury: more questions requiring discussion

In cirrhosis with ascites, hepatorenal syndrome (HRS) is a specific prerenal dysfunction unresponsive to fluid volume expansion. Acute-on-chronic liver failure (ACLF) comprises a group of clinical syndromes with multiple organ failure and early high mortality. There are differences in the characterization of ACLF between the Eastern and Western medical communities. Patients with ACLF and acute kidney injury (AKI) have more structural injuries, contributing to confusion in diagnosing HRS-AKI. In this review, we discuss progress in the pathogenesis, diagnosis, and management of HRS-AKI, especially in patients with ACLF. Controversy regarding HRS-AKI in ACLF and acute liver failure, hepatic carcinoma, shock, sepsis, and chronic kidney disease is also discussed. Research on the treatment of HRS-AKI with ACLF needs to be more actively pursued to improve disease prognosis.

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.

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.

Current knowledge about biomarkers of acute kidney injury in liver cirrhosis

Acute kidney injury (AKI) is common in advanced cirrhosis. Prerenal azotemia, hepatorenal syndrome, and acute tubular necrosis are the main causes of AKI in patients with cirrhosis. Evaluation of renal function and differentiation between functional and structural kidney injury are important issues in the management of cirrhosis. However, AKI in cirrhosis exists as a complex clinical spectrum rather than concrete clinical entity. Based on current evidence, changes in serum creatinine (Cr) levels remain the most appropriate standard for defining AKI in cirrhosis. However, serum Cr has a limited role in assessing renal function in this population. This review examines previous studies that investigated the ability of recent biomarkers for AKI in cirrhosis from the perspective of earlier and accurate diagnosis, classification of AKI phenotype, and prediction of clinical outcomes. Serum cystatin C and urine neutrophil gelatinase-associated lipocalin have been extensively studied in cirrhosis, and have facilitated improved diagnosis and prognosis prediction in patients with AKI. In addition, urine N-acetyl-β-D-glucosaminidase, interleukin 18, and kidney injury molecule 1 are other promising biomarkers for advanced cirrhosis. However, the clinical significance of these markers remains unclear because there are no cut-off values defining the normal range and differentiating phenotypes of AKI. In addition, AKI has been defined in terms of serum Cr, and renal biopsy-the gold standard-has not been carried out in most studies. Further discovery of innovate biomarkers and incorporation of various markers could improve the diagnosis and prognosis prediction of AKI, and will translate into meaningful improvements in patient outcomes.

Recent advances in the understanding and management of hepatorenal syndrome

Renal dysfunction occurs frequently in hospitalized patients with advanced chronic liver disease (ACLD)/cirrhosis and has profound prognostic implications. In ACLD patients with ascites, hepatorenal syndrome (HRS) may result from circulatory dysfunction that leads to reduced kidney perfusion and glomerular filtration rate (in the absence of structural kidney damage). The traditional subclassification of HRS has recently been replaced by acute kidney injury (AKI) type of HRS (HRS-AKI) and non-AKI type of HRS (HRS-NAKI), replacing the terms “HRS type 1” and “HRS type 2”, respectively. Importantly, the concept of absolute serum creatinine (sCr) cutoffs for diagnosing HRS was partly abandoned and short term sCr dynamics now may suffice for AKI diagnosis, which facilitates early treatment initiation that may prevent the progression to HRS-AKI or increase the chances of AKI/HRS-AKI reversal. Recent randomized controlled trials have established (a) the efficacy of (long-term) albumin in the prevention of complications of ascites (including HRS-AKI), (b) the benefits of transjugular intrahepatic portosystemic shunt placement in patients with recurrent ascites, and (c) the superiority of terlipressin over noradrenaline for the treatment of HRS-AKI in the context of acute-on-chronic liver failure. This review article aims to summarize recent advances in the understanding and management of HRS.

End-stage liver disease: Management of hepatorenal syndrome

Hepatorenal syndrome (HRS) is a serious complication of cirrhosis with high morbidity and mortality rates. Recently, the definition of HRS type 1 has been updated and is now called HRS-AKI. This new definition reduces the risk of delaying HRS treatment and eliminates the need to establish a minimum creatinine cut-off for the diagnosis of HRS-AKI. From a pathophysiological point of view, newly identified mechanisms involved in the development of HRS are related to the inflammatory response, conditioning the development of extrahepatic organ dysfunction in patients with cirrhosis. One of the main challenges for the diagnosis of HRS is the validation of new biomarkers to obtain an early and differential diagnosis of kidney injury (eg HRS vs. ATN). Treatment of HRS is based on the use of vasoconstrictive agents in combination with albumin and terlipressin is the most widely used vasoconstrictor drug, with a high response rate. The effects of a continuous infusion of terlipressin at a dose of 2-12 mg/day was similar to bolus administration, but with lower rates of adverse events. Finally, MELD/MELD-Na which includes creatinine as one of its main determinants gives AKI-HRS patients priority on the waiting list (WL) for liver transplant (LT). However, the MELD and MELD-Na scores are reduced in responding patients, resulting a longer waiting time in these patients than in non-responders. Thus, the initial MELD/MELD-Na score (pre-treatment value) should be used to prioritize patients on the WL for LT in these cases.

Development and validation of a prognostic model for patients with hepatorenal syndrome: A retrospective cohort study

BACKGROUND

Hepatorenal syndrome (HRS) is a severe complication of cirrhosis with high mortality, which necessitates accurate clinical decision. However, studies on prognostic factors and scoring systems to predict overall survival of HRS are not enough. Meanwhile, a multicenter cohort study with a long span of time could be more convincing.

AIM

To develop a novel and effective prognostic model for patients with HRS and clarify new prognostic factors.

METHODS

We retrospectively enrolled 1667 patients from four hospitals, and 371 eligible patients were finally analyzed to develop and validate a novel prognostic model for patients with HRS. Characteristics were compared between survivors and non-survivors, and potential prognostic factors were selected according to the impact on 28-d mortality. Accuracy in predicting 28-d mortality was compared between the novel and other scoring systems, including Model for End-Stage Liver Disease (MELD), Chronic Liver Failure-Sequential Organ Failure Assessment (CLIF-SOFA), and Chinese Group on the Study of Severe Hepatitis B-Acute-on-Chronic Liver Failure (COSSH-ACLF).

RESULTS

Five prognostic factors, comprised of gender, international normalized ratio, mean corpuscular hemoglobin concentration, neutrophil percentage, and stage, were integrated into a new score, GIMNS; stage is a binary variable defined by the number of failed organs. GIMNS was positively correlated with MELD, CLIF-SOFA, and COSSH-ACLF. Additionally, it had better accuracy [area under the receiver operating characteristic curve (AUROC): 0.830] than MELD (AUROC: 0.759), CLIF-SOFA (AUROC: 0.767), and COSSH-ACLF (AUROC: 0.759) in the derivation cohort (P < 0.05). It performed better than MELD and CLIF-SOFA in the validation cohort (P < 0.050) and had a higher AUROC than COSSH-ACLF (P = 0.122).

CONCLUSION

We have developed a new scoring system, GIMNS, to predict 28-d mortality of HRS patients. Mean corpuscular hemoglobin concentration and stage were first proposed and found to be related to the mortality of HRS. Additionally, the GIMNS score showed better accuracy than MELD and CLIF-SOFA, and the AUROC was higher than that of COSSH-ACLF.

Hillien SA, Kalim S, Nigwekar SU, Flood JG, Nixon A, Simonetto DA, Juncos LA, Karakala N, Wadei HM, Regner KR, Belcher JM, Nadim MK, Garcia-Tsao G, Velez JCQ, Parikh SM, Chung RT. Urinary NGAL as a Diagnostic and Prognostic Marker for Acute Kidney Injury in Cirrhosis: A Prospective Study

INTRODUCTION

Urinary neutrophil gelatinase-associated lipocalin (NGAL) has shown promise in differentiating acute tubular necrosis (ATN) from other types of acute kidney injuries (AKIs) in cirrhosis, particularly hepatorenal syndrome (HRS). However, NGAL is not currently available in clinical practice in North America.

METHODS

Urinary NGAL was measured in a prospective cohort of 213 US hospitalized patients with decompensated cirrhosis (161 with AKI and 52 reference patients without AKI). NGAL was assessed for its ability to discriminate ATN from non-ATN AKI and to predict 90-day outcomes.

RESULTS

Among patients with AKI, 57 (35%) had prerenal AKI, 55 (34%) had HRS, and 49 (30%) had ATN, with a median serum creatinine of 2.0 (interquartile range 1.5, 3.0) mg/dL at enrollment. At an optimal cutpoint of 244 μg/g creatinine, NGAL distinguished ATN (344 [132, 1,429] μg/g creatinine) from prerenal AKI (45 [0, 154] μg/g) or HRS (110 [50, 393] μg/g; P < 0.001), with a C statistic of 0.762 (95% confidence interval 0.682, 0.842). By 90 days, 71 of 213 patients (33%) died. Higher median NGAL was associated with death (159 [50, 865] vs 58 [0, 191] μg/g; P < 0.001). In adjusted and unadjusted analysis, NGAL significantly predicted 90-day transplant-free survival (P < 0.05 for all Cox models) and outperformed Model for End-Stage Liver Disease score by C statistic (0.697 vs 0.686; P = 0.04), net reclassification index (37%; P = 0.008), and integrated discrimination increment (2.7%; P = 0.02).

DISCUSSION

NGAL differentiates the type of AKI in cirrhosis and may improve prediction of mortality; therefore, it holds potential to affect management of AKI in cirrhosis.

Endothelial dysfunction markers predict short-term mortality in patients with severe alcoholic hepatitis

OBJECTIVES

Alcoholic hepatitis (AH) is a severe condition characterized by a marked inflammatory response and high short-term mortality. Endothelial dysfunction (ED) is an early event in vascular and inflammatory disorders. The aim of this study is to evaluate ED in AH patients.

METHODS

Prognostic value of ED biomarkers was evaluated in patients with severe AH (n = 67), compensated alcoholic cirrhosis (n = 15), heavy drinkers without liver disease (n = 15) and controls (n = 9), and in a validation cohort of 50 patients with AH. Gene expression of ED markers was analyzed in liver tissue.

RESULTS

Plasma levels of ED markers such as vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), E-selectin and von Willebrand factor (vWF) increased along alcohol-related liver disease (ALD) progression. Intergroup analysis showed a significant increase of these markers in AH patients. In addition, VCAM-1 showed a positive correlation with Maddrey, MELD and ABIC scores and inflammation parameters (i.e. C-reactive protein and LPS levels). Importantly, levels of VCAM-1 were higher in patients with increased mortality and were independently associated with short-term survival (90-day) when adjusted by ABIC score. These results were confirmed in an independent cohort of AH patients. In addition, severe AH patients showed altered hepatic expression of ED markers.

CONCLUSIONS

In this study we show that advanced ALD and particularly severe AH is associated with an increase of ED biomarkers, which correlate with patient outcomes. These results suggest that ED may be a pathogenic event in AH and highlight endothelial factors as potential biomarkers in AH.

Advances in the Management of Renal Dysfunction in Patients With Cirrhosis

Renal dysfunction frequently develops in patients with advanced liver disease. Renal dysfunction in this setting is associated with adverse outcomes and an unfavorable prognosis. Hepatorenal syndrome (HRS), defined as worsening renal function in patients with advanced cirrhosis that can present either acutely (<3 months) or more indolently in the absence of other etiologies, remains a common cause of acute kidney injury. If reversal is not promptly achieved, rapid decline to mortality is common. Volume expansion and vasoconstrictors are the mainstays of therapy. Terlipressin, a vasopressin analogue licensed in several countries but not in the United States, is currently used for the treatment of HRS. Timely liver transplantation remains the only effective therapeutic option for a large group of patients with persistent renal dysfunction despite pharmacotherapy. In patients with underlying chronic renal dysfunction, simultaneous liver-kidney transplantation should be considered. The aim of this article is to present an overview of renal dysfunction in patients with cirrhosis, including diagnosis and management.

Intestinal SIRT1 Deficiency-Related Intestinal Inflammation and Dysbiosis Aggravate TNFα-Mediated Renal Dysfunction in Cirrhotic Ascitic Mice

In advanced cirrhosis, the TNFα-mediated intestinal inflammation and bacteria dysbiosis are involved in the development of inflammation and vasoconstriction-related renal dysfunction. In colitis and acute kidney injury models, activation of SIRT1 attenuates the TNFα-mediated intestinal and renal abnormalities. This study explores the impacts of intestinal SIRT1 deficiency and TNFα-mediated intestinal abnormalities on the development of cirrhosis-related renal dysfunction. Systemic and renal hemodynamics, intestinal dysbiosis [cirrhosis dysbiosis ratio (CDR) as marker of dysbiosis], and direct renal vasoconstrictive response (renal vascular resistance (RVR) and glomerular filtration rate (GFR)) to cumulative doses of TNFα were measured in bile duct ligated (BDL)-cirrhotic ascitic mice. In SIRT1^IEC-KO-BDL-ascitic mice, the worsening of intestinal dysbiosis exacerbates intestinal inflammation/barrier dysfunction, the upregulation of the expressions of intestinal/renal TNFα-related pathogenic signals, higher TNFα-induced increase in RVR, and decrease in GFR in perfused kidney. In intestinal SIRT1 knockout groups, the positive correlations were identified between intestinal SIRT1 activity and CDR. Particularly, the negative correlations were identified between CDR and RVR, with the positive correlation between CDR and GFR. In mice with advanced cirrhosis, the expression of intestinal SIRT1 is involved in the linkage between intestinal dysbiosis and vasoconstriction/hypoperfusion-related renal dysfunction through the crosstalk between intestinal/renal TNFα-related pathogenic inflammatory signals.

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.

HEP-Net opinion on the management of ascites and its complications in the setting of decompensated cirrhosis in the resource constrained environment of Pakistan

Approximately one half of patients develop ascites within 10 years of diagnosis of compensated cirrhosis. It is a poor prognostic indicator, with only 50% surviving beyond two years. Mortality worsens significantly to 20% to 50% at one year if the ascites becomes refractory to medical therapy. Pakistan has one of the highest prevalence of viral hepatitis in the world and patients with ascites secondary to liver cirrhosis make a major percentage of both inpatient and outpatient burden. Studies indicate that over 80% of patients admitted with ascites have liver cirrhosis as the cause.

This expert opinion suggests proper assessment of patients with ascites in the presence of underlying cirrhosis. This expert opinion includes appropriate diagnosis and management of uncomplicated ascites, refractory ascites and complicated ascites (including spontaneous bacterial peritonitis (SBP) ascites, hepatorenal syndrome (HRS) and hyponatremia. The purpose behind this expert opinion is to help consultants, postgraduate trainees, medical officers and primary care physicians optimally manage their patients with cirrhosis and ascites in a resource constrained setting as is often encountered in a developing country like Pakistan.

Immune Regulatory Mediators in Plasma from Patients With Acute Decompensation Are Associated With 3-Month Mortality

BACKGROUND & AIMS

Infection is a common cause of death in patients with cirrhosis. We investigated the association between the innate immune response and death within 3 months of hospitalization.

METHODS

Plasma samples were collected on days 1, 5, 10, and 15 from participants recruited into the albumin to prevent infection in chronic liver failure feasibility study. Patients with acute decompensated cirrhosis were given albumin infusions at 10 hospitals in the United Kingdom. Data were obtained from 45 survivors and 27 non-survivors. We incubated monocyte-derived macrophages from healthy individuals with patients' plasma samples and measured activation following lipopolysaccharide administration, determined by secretion of tumor necrosis factor and soluble mediators of inflammation. Each analysis included samples from 4 to 14 patients.

RESULTS

Plasma samples from survivors vs non-survivors had different inflammatory profiles. Levels of prostaglandin E2 were high at times of patient hospitalization and decreased with albumin infusions. Increased levels of interleukin 4 (IL4) in plasma collected at day 5 of treatment were associated with survival at 3 months. Incubation of monocyte-derived macrophages with day 5 plasma from survivors, pre-incubated with a neutralizing antibody against IL4, caused a significant increase in tumor necrosis factor production to the level of non-survivor plasma. Although baseline characteristics were similar, non-survivors had higher white cell counts and levels of C-reactive protein and renal dysfunction.

CONCLUSIONS

We identified profiles of inflammatory markers in plasma that are associated with 3-month mortality in patients with acute decompensated cirrhosis given albumin. Increases in prostaglandin E2 might promote inflammation within the first few days after hospitalization, and increased levels of plasma IL4 at day 5 are associated with increased survival. Clinicaltrialsregister.eu: EudraCT 2014-002300-24.

Ascites and Hepatorenal Syndrome

Ascites occurs in up to 70% of patients during the natural history of cirrhosis. Management of uncomplicated ascites includes sodium restriction and diuretic therapy, whereas that for refractory ascites (RA) is regular large-volume paracentesis with transjugular intrahepatic portosystemic shunt being offered in appropriate patients. Renal impairment occurs in up to 50% of patients with RA with type 1 hepatorenal syndrome (HRS) being most severe. Liver transplant remains the definitive treatment of eligible candidates with HRS, whereas combined liver and kidney transplant should be considered in patients requiring dialysis for more than 4 to 6 weeks or those with underlying chronic kidney disease.

Admission plasma uromodulin and the risk of acute kidney injury in hospitalized patients with cirrhosis: a pilot study

Acute kidney injury (AKI) is a common complication in hospitalized patients with cirrhosis. Uromodulin, a protein uniquely produced by the kidney and released both in the urine and circulation, has been shown to regulate AKI and is linked to tubular reserve. Although low levels of urine uromodulin are associated with AKI after cardiac surgery, it is unclear whether circulating uromodulin can stratify the risk of AKI, particularly in a susceptible population such as hospitalized patients with cirrhosis. Thus, we investigated whether plasma uromodulin measured at the time of admission is associated with subsequent hospital-acquired AKI (defined by a rise in serum creatinine >0.3mg/dL within 48 h or ≥ 1.5 times baseline) in patients with cirrhosis. A total of 98 patients [mean age 54 yr, Model for Endstage Liver Disease Sodium (MELD-Na) score 19, and baseline creatinine of 0.95 mg/dL] were included, of which 13% (n = 13) developed AKI. Median uromodulin levels were significantly lower in patients who developed AKI compared with patients who did not (9.30 vs. 13.35 ng/mL, P = 0.02). After adjusting for age, sex, diabetes, hypertension, albumin, and MELD-Na score as covariates on multivariable logistic regression, uromodulin was independently associated with AKI [odd ratios of 1.19 (95% confidence interval 1.02, 1.37; P = 0.02)]. Lower uromodulin levels on admission are associated with increased odds of subsequent AKI in hospitalized patients with cirrhosis. Further studies are needed to better understand the role of uromodulin in the pathogenesis and as a predictive biomarker of AKI in this population.NEW & NOTEWORTHY In this study, we found that admission plasma uromodulin levels are significantly lower in patients who developed subsequent acute kidney injury (AKI) during their hospital stay compared with patients who did not. Additionally, uromodulin is independently associated with AKI development after adjusting for clinically relevant parameters such as age, sex, diabetes, hypertension, severity of cirrhosis, and kidney function. To our knowledge, this is the first study linking plasma uromodulin with AKI development in patients with cirrhosis.

Acute kidney injury spectrum in patients with chronic liver disease: Where do we stand?

Acute kidney injury (AKI) is a common complication of liver cirrhosis and is of the utmost clinical and prognostic relevance. Patients with cirrhosis, especially decompensated cirrhosis, are more prone to develop AKI than those without cirrhosis. The hepatorenal syndrome type of AKI (HRS–AKI), a spectrum of disorders in prerenal chronic liver disease, and acute tubular necrosis (ATN) are the two most common causes of AKI in patients with chronic liver disease and cirrhosis. Differentiating these conditions is essential due to the differences in treatment. Prerenal AKI, a more benign disorder, responds well to plasma volume expansion, while ATN requires more specific renal support and is associated with substantial mortality. HRS–AKI is a facet of these two conditions, which are characterized by a dysregulation of the immune response. Recently, there has been progress in better defining this clinical entity, and studies have begun to address optimal care. The present review synopsizes the current diagnostic criteria, pathophysiology, and treatment modalities of HRS–AKI and as well as AKI in other chronic liver diseases (non-HRS–AKI) so that early recognition of HRS–AKI and the appropriate management can be established.