Pathophysiology of Hepatorenal Syndrome - Acute Kidney Injury

Urinary metabolomics analysis of patients with renal tubular dysfunction after PCI surgery

PURPOSE

Differences in metabolic profiles were used to search for urinary metabolic markers in patients with tubular dysfunction after percutaneous coronary intervention (PCI).

METHODS

In this study, 50 patients with renal tubule dysfunction 6 h after PCI were collected and urine samples before PCI were used as control group and 6 h after PCI were used as observation group. The urine samples were processed by high-speed centrifugation, filtered by microporous membrane, and the superclear was obtained for LC-MS detection and analysis, and their metabolic profiles and related data were obtained.

RESULTS

Compared with the control group, α1-MG, NAG and Cys-C in the urine of the observation group were significantly increased, and the difference was statistically significant (P < 0.05). After the urine samples were processed by LC-MS technology, SIMCA realized the visual visualization of the score plots of PCA, OPLS-DA and other models, and then verified by statistical methods, it was found that there were different metabolites in the urine of patients before and after PCI. The HMDB database was used to search for differential metabolites and 16 different metabolites such as L-ornithine, oleic acid amide, D-histidine, p-hydroxyphenyllactic acid, acetylmethionine, N-(2-furanyl) glycine, cholesterol laurate, cholic acid, 1-methylguanine, L-hydrochloric acid, homovanillic acid, alpha-keto-isocaproic acid, 3-β-hydroxy-D5-cholenoic acid, adenine, palmitic acid, pentadecanoic acid. Pathway Analysis in MetaboAnalyst5.0 was used to analyze the metabolic pathways of 16 different metabolites. Finally, a total of 11 metabolic pathways were matched. Finally, we believe that the biosynthetic pathway of arginine and the metabolic pathway of alanine, aspartate and glutamate are most relevant to tubular dysfunction after percutaneous coronary intervention (PCI).

CONCLUSION

In this study, LC-MS technology was used to analyze urine samples from CIN patients and patients with coronary heart disease before and after PCI and a total of 16 different metabolites were screened out, which may serve as potential biomarkers to help diagnose renal tubular dysfunction. There are 11 metabolic pathways in the body involved in the occurrence and development of renal tubular dysfunction after angiography and the biosynthesis pathway of arginine and the metabolic pathway of alanine, aspartate and glutamate may play the most important role in the occurrence and development of renal tubular dysfunction.

Liver-Kidney Crosstalk in Major Pediatric Diseases: Unraveling the Complexities and Clinical Challenges

The liver and kidneys are two of the most vital organs, each with distinct but overlapping functions essential for maintaining homeostasis. The complex interplay between these organs, commonly referred to as liver-kidney crosstalk, plays a crucial role in the pathophysiology of several acute and chronic conditions in childhood. Despite its importance, the precise biological mechanisms driving this interaction remain incompletely understood. This crosstalk is particularly significant in various pediatric diseases (e.g., Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), Hepatorenal Syndrome (HRS), genetic and metabolic disorders, etc.) where shared pathophysiological factors-including systemic inflammation, metabolic disturbances, oxidative stress, and vascular dysfunction-simultaneously affect both organs. Clinically, this interaction presents unique challenges in diagnosing, managing, and treating liver-kidney diseases in affected children. Understanding the pathogenic mechanisms underlying liver-kidney crosstalk is essential for improving patient care and outcomes through an integrated, multidisciplinary approach and personalized treatment strategies. This review aims to explore liver-kidney crosstalk in key pediatric diseases, offering a comprehensive overview of current knowledge, clinical challenges, and potential therapeutic interventions in this complex field.

Optimal Management of the Inpatient With Decompensated Cirrhosis

Over the past several years, there has been a wealth of new data pertaining to the management of complications of cirrhosis, resulting in several important updates to best practices and consensus guidelines. Despite these advancements and numerous recent targeted quality initiatives, hospitalizations resulting from complications of cirrhosis remain frequent, costly and associated with poor patient outcomes. An emphasis on evidence-based management of hospitalized patients with decompensated cirrhosis has the potential to decrease readmission rates and length of stay while improving overall patient outcomes. Herein, we provide an updated, evidence-based overview of the optimal inpatient management of the most frequently encountered complications associated with cirrhosis.

Renal Dysfunction and Liver Transplantation

Renal dysfunction is common in patients undergoing liver transplant (LT) evaluation, thereby making it imperative for hepatologists to know how to diagnose, manage, and optimize treatment of acute kidney injury (AKI) and chronic kidney disease. This article reviews pre-transplant, peri-transplant, and post-transplant AKI diagnosis and management, and the role of renal replacement therapy in LT candidates.

Maternal hemodynamics assessment: Key to unlocking ignored functionalities of the female circulation

This chapter focuses on currently underappreciated aspects of the maternal circulation: blood pressure phenotypes, venous hemodynamics, intra-abdominal pressure, and body water homeostasis. Based on the hemodynamic balance between cardiac output and total peripheral resistance, flow-dominant and resistance-dominant phenotypes of normotension and hypertension exist, with different impacts on gestational outcome. Cardiac diastolic function and venous hemodynamics play a prominent role in gestational changes in cardiac output. An increase in intra-abdominal pressure during pregnancy interferes with body water volume homeostasis, similar to syndromes of multi-organ dysfunctions in non-pregnant individuals. Today, non-invasive maternal hemodynamics assessment allows for obtaining important information on these ignored circulatory functions in addition to conventional sphygmomanometric blood pressure measurement. This offers perspectives to improve current strategies for screening, diagnosis, and management of gestational hypertension disorders, a path, however, to be paved first by intensified multifaceted and multidisciplinary research.

Early blood pressure drop predicts renal function deterioration and mortality in ICU patients with liver failure: a retrospective cohort study

OBJECTIVE

To investigate the association between early blood pressure drop and worsening renal function (WRF) in ICU patients with liver failure and to evaluate their clinical outcomes.

DESIGN

Retrospective observational study.

SETTING

Intensive Care Medicine.

PATIENTS

Patients admitted to the ICU for the first time during their first hospitalization; diagnosed with liver failure according to the International Classification of Diseases, Ninth and Tenth Revision codes; and aged ≥18 years were included. Patients with a peak systolic blood pressure (SBP) drop of <0 mmHg were excluded.

INTERVENTION

We analyzed data of ICU patients with liver failure from the Medical Information Mart for Intensive Care IV version 2.2 database. Descriptive statistics, analysis of variance, Kruskal-Wallis test, and chi-square test were employed for analysis. Multivariate linear regression models were used to assess the determinants of blood pressure decline. Cox proportional hazards and generalized additive models were used to evaluate MAIN VARIABLES OF INTEREST: The relationship between blood pressure decline, WRF, and 60-day in-hospital mortality were evaluated, along with subgroup analyses.

RESULTS

Peak SBP drop was independently associated with higher risks of WRF (P < 0.001) and 60-day in-hospital mortality (P < 0.001), even after adjusting for potential confounders, including baseline SBP. The independent risk relationship observed between peak diastolic blood pressure, mean arterial pressure drop, and the occurrence of WRF and 60-day in-hospital mortality was similar.

CONCLUSIONS

In ICU patients with liver failure, a significant early drop in blood pressure was associated with a higher incidence of WRF, increased risk of 60-day in-hospital mortality, and poorer prognoses.

Update on the Complications and Management of Liver Cirrhosis

Liver cirrhosis represents the advanced pathological stage of chronic liver disease, characterized by the progressive destruction and regeneration of the hepatic parenchyma over years, culminating in fibrosis and disruption of the vascular architecture. As a leading global cause of morbidity and mortality, it continues to affect millions worldwide, imposing a substantial burden on healthcare systems. Alcoholic/nonalcoholic fatty liver disease and chronic viral hepatitis infection, hepatitis C (HCV) in particular, remain leading causes of cirrhosis. Despite significant advances in understanding the pathogenesis of cirrhosis, its management is still complex due to the multifaceted complications, including ascites, hepatic encephalopathy, variceal bleeding, and hepatocellular carcinoma, all of which severely compromise the patient outcomes and quality of life. This review aims at filling a critical gap by providing a comprehensive summary of the latest evidence on the complications and management of liver cirrhosis. Evidence-based therapies targeting both the etiologies and complications of cirrhosis are essential for improving outcomes. While liver transplantation is considered a definitive cure, advancements in pharmacological therapies offer promising avenues for halting and potentially reversing disease progression. This review summarizes the latest management strategies for cirrhosis and its associated complications, emphasizing the importance of early intervention and novel therapeutic options for improving outcomes and quality of life in affected individuals.

Development and validation of a machine learning-based prediction model for hepatorenal syndrome in liver cirrhosis patients using MIMIC-IV and eICU databases

Hepatorenal syndrome (HRS) is a key contributor to poor prognosis in liver cirrhosis. This study aims to leverage the database to build a predictive model for early identification of high-risk patients. From two sizable public databases, we retrieved pertinent information about the cirrhosis patients' therapies, comorbidities, laboratory results, and demographics. Patients from the eICU database served as a test set for external validation, while patients from the MIMIC database were divided into training and validation groups. Variables were screened using LASSO regression, Extreme Gradient Boosting (XG Boost), and Random Forest (RF). Core risk factors were determined from the intersection of the three methods. A predictive model was constructed using multivariable logistic regression and visualized via a nomogram. Model performance was assessed using ROC curves, decision curve analysis (DCA), clinical impact curves (CIC), and calibration curves. Eight critical variables associated with HRS were identified using machine learning methods. The final predictive model, based on five key variables-spontaneous bacterial peritonitis, red blood cell count, creatinine, activated partial thromboplastin time, and total bilirubin-showed excellent discrimination, with AUCs of 0.832 (95% CI 0.8069-0.8563) in the training set and 0.8415 (95% CI 0.8042-0.8789) in the validation set. The AUC in the external test set was 0.8212 (95% CI 0.7784-0.864). By integrating the MIMIC-IV database and machine learning algorithms, we developed an effective predictive model for HRS in liver cirrhosis patients, providing a robust tool for early clinical intervention.

Predictors of Acute Kidney Injury Resolution and Associated Clinical Outcomes Among Hospitalized Patients with Cirrhosis

Background: Acute kidney injury (AKI) is one of the common complications of liver cirrhosis. It occurs in nearly 20% of patients with cirrhosis who are hospitalized. Prior literature demonstrated that the AKI occurrence in patients with cirrhosis is independently associated with higher mortality. However, there are data assessing predictors and outcomes of AKI resolution in hospitalized patients with cirrhosis. Therefore, the aim of the current study was to identify clinical predictors of AKI resolution among inpatients with cirrhosis that are easily obtained and to evaluate the clinical outcomes of those patients. Methods: The current study is a retrospective cohort of patients with cirrhosis who were hospitalized and had AKI between 2012 and 2020 at a tertiary referral center. Patients included in this study were identified using the International Classification of Diseases 9 codes and then they were manually verified by two independent chart reviewers. AKI was classified according to the AKI Network (AKIN) serum creatinine (Cr) criteria, with AKIN resolution defined as AKIN stage 1 or lower at the time of discharge, while unresolved AKIN was defined as AKIN stage 2 or 3 at the time of discharge. For univariate analysis, Fisher's exact and the two-sample T-test were utilized. For multivariable analysis, stepwise logistic regression was performed to evaluate variables associated with AKIN resolution. Survival curves were estimated and compared using the Kaplan-Meier method and Log-Rank Test. A p-value cutoff of 0.05 was used for statistical significance. Results: Between 2012 and 2020, there were 140 patients who were included (59% males). The majority of patients had viral hepatitis (54%) as the cirrhosis etiology with 80% of them having hepatitis C virus. Most patients had fluid-responsive AKI (49%), and stage 1 AKIN (69%). In terms of outcomes, the majority of patients (117 patients; 84%) had AKIN resolution at the time of discharge. In the multivariable analysis, after adjusting for clinical meaningful variables, our study shows that higher albumin value at the time of admission (adjusted Odds Ratio "aOR" = 3.28; p = 0.01) and non-metabolic dysfunction-associated steatotic liver disease (non-MASLD) cirrhosis (aOR = 9.43; p < 0.01) were variables associated with higher odds of AKIN resolution at the time of discharge. Conversely, we show that a higher Cr value at the time of admission was associated with lower odds of AKIN resolution at the time of discharge (aOR = 0.31; p < 0.01). When evaluating mortality, patients with unresolved AKIN at the time of discharge had higher rates of in-hospital mortality (p < 0.01) compared to those with resolved AKIN. Survival curve analyses using the Kaplan-Meier method indicated that patients with resolved AKIN experienced higher 90-day survival rates (p < 0.01). Additionally, those with resolved AKIN demonstrated greater transplant-free survival compared to patients with unresolved AKIN at both the 1-year (p = 0.04) and 3-year (p < 0.01) follow-ups. Conclusions: When evaluating clinical predictors of AKIN resolution in admitted patients with cirrhosis, our study showed that a higher admission albumin value and non-MASLD etiology of cirrhosis were associated with higher odds of AKIN resolution at the time of discharge. Conversely, a higher admission Cr value was associated with lower odds of AKIN resolution at the time of discharge. We also demonstrate that AKIN resolution during index admission was associated with improved short- and long-term transplant-free survival (up to 3 years). Our findings warrant external validation in larger cohorts to further evaluate the impact of inpatient AKI resolution on cirrhosis outcomes. Our findings can help clinicians predict AKIN outcomes and encourage more aggressive management of AKI, especially in high-risk patients, which can improve mortality.

Designing clinical trials to address alcohol use and alcohol-associated liver disease: an expert panel Consensus Statement

Most patients with alcohol-associated liver disease (ALD) engage in heavy drinking defined as 4 or more drinks per day (56 g) or 8 (112 g) or more drinks per week for women and 5 or more drinks per day (70 g) or 15 (210 g) or more drinks per week for men. Although abstinence from alcohol after diagnosis of ALD improves life expectancy and reduces the risk of decompensation of liver disease, few studies have evaluated whether treatment of alcohol use disorders will reduce progression of liver disease and improve liver-related outcomes. In November 2021, the National Institute of Alcohol Abuse and Alcoholism commissioned a task force that included hepatologists, addiction medicine specialists, statisticians, clinical trialists and members of regulatory agencies to develop recommendations for the design and conduct of clinical trials to evaluate the effect of alcohol use, particularly treatment to reduce or eliminate alcohol use in patients with ALD. The task force conducted extensive reviews of relevant literature on alcohol use disorders and ALD. Findings were presented at one in-person meeting and discussed over the next 16 months to develop the final recommendations. As few clinical trials directly address this topic, the 28 recommendations approved by all members of the task force represent a consensus of expert opinions.

Long-Term Continuous Terlipressin Infusion Improves Cardiac Reserve in Patients With Decompensated Cirrhosis

BACKGROUND AND AIMS

Cardiac dysfunction is a key factor in the pathogenesis of hepatorenal syndrome, for which terlipressin is the recommended first-line treatment. This study investigates whether long-term terlipressin can ameliorate the subclinical cardiac dysfunction observed in decompensated cirrhosis.

METHODS

Twenty-two patients with decompensated cirrhosis and ascites enrolled in a prospective study of home continuous terlipressin infusion were included. Cardiac function was assessed using dobutamine stress echocardiogram before and after 12 weeks of terlipressin. The primary outcome was the impact of terlipressin on cardiac reserve, the change in cardiac output (CO) in response to stress.

RESULTS

The median age was 61 years (interquartile range, 56-64 years), the median Model for End-Stage Liver Disease score was 15 (interquartile range, 12.3-17.0), and 72.7% were male. The increase in CO in response to low-dose dobutamine was significantly higher following terlipressin (↑4.0 L/min [↑57.8%]) as compared with baseline (↑1.8 L/min [21.3%]) (P = .0001). The proportion of patients with impaired cardiac reserve (defined by ΔCO <25% after low-dose dobutamine) reduced from 81.8% at baseline to 40.9% after terlipressin, (P = .02), driven primarily by improvement in inotropic function. Resting CO decreased significantly after terlipressin from 8.9 ± 2.2 L/min to 7.2 ± 1.8 L/min (normal range 5-6 L/min) (P < .001), due to a decrease in stroke volume from 108 to 86 mL/beat (P = .006).

CONCLUSIONS

Long-term continuous terlipressin infusion resulted in a significant increase in cardiac reserve and attenuation of the hyperdynamic state usually observed in decompensated cirrhosis. These data provide important mechanistic insight into the pathogenesis and reversibility of cardiac dysfunction in cirrhosis. Future studies are required to evaluate whether long-term terlipressin can prevent hepatic decompensating events such as hepatorenal syndrome in high-risk individuals. Australian New Zealand Clinical Trials Registry, Number: ACTRN12619000891123.

Review article: Recent advances in ascites and acute kidney injury management in cirrhosis

BACKGROUND

Better understanding of disease pathophysiology has led to advances in managing ascites and its associated complications including hepatorenal syndrome-acute kidney Injury (HRS-AKI), especially medicinal and interventional advances.

AIM

To review the latest changes in the management of ascites and HRS-AKI.

METHODS

A literature search was conducted in Pubmed, using the keywords cirrhosis, ascites, renal dysfunction, acute kidney injury, hepatorenal syndrome, beta-blockers, albumin, TIPS and vasoconstrictors, including only publications in English.

RESULTS

The medicinal advances include earlier treatment of clinically significant portal hypertension to delay the onset of ascites and the use of human albumin solution to attenuate systemic inflammation thus improving the haemodynamic changes associated with cirrhosis. Furthermore, new classes of drugs such as sodium glucose co-transporter 2 are being investigated for use in patients with cirrhosis and ascites. For HRS-AKI management, newer pharmacological agents such as vasopressin partial agonists and relaxin are being studied. Interventional advances include the refinement of TIPS technique and patient selection to improve outcomes in patients with refractory ascites. The development of the alfa pump system and the study of outcomes associated with the use of long-term palliative abdominal drain will also serve to improve the quality of life in patients with refractory ascites.

CONCLUSIONS

New treatment strategies emerged from better understanding of the pathophysiology of ascites and HRS-AKI have shown improved prognosis in these patients. The future will see many of these approaches confirmed in large multi-centre clinical trials with the aim to benefit the patients with ascites and HRS-AKI.

Hepatocardiorenal syndrome in liver cirrhosis: Recognition of a new entity?

Emerging evidence and perspectives have pointed towards the heart playing an important role in hepatorenal syndrome (HRS), outside of conventional understanding that liver cirrhosis is traditionally considered the sole origin of a cascade of pathophysiological mechanisms directly affecting the kidneys in this context. In the absence of established heart disease, cirrhotic cardiomyopathy may occur more frequently in those with liver cirrhosis and kidney disease. It is a specific form of cardiac dysfunction characterized by blunted contractile responsiveness to stress stimuli and altered diastolic relaxation with electrophysiological abnormalities. Despite the clinical description of these potential cardiac-related complications of the liver, the role of the heart has traditionally been an overlooked aspect of circulatory dysfunction in HRS. Yet from a physiological sense, temporality (prior onset) of cardiorenal interactions in HRS and positive effects stemming from portosystemic shunting demonstrated an important role of the heart in the development and progression of kidney dysfunction in cirrhotic patients. In this review, we discuss current concepts surrounding how the heart may influence the development and progression of HRS, and the role of systemic inflammation and endothelial dysfunction causing circulatory dysfunction within this setting. The temporality of heart and kidney dysfunction in HRS will be discussed. For a subgroup of patients who receive portosystemic shunting, the dynamics of cardiorenal interactions following treatment is reviewed. Continued research to determine the unknowns in this topic is anticipated, hopefully to further clarify the intricacies surrounding the liver-heart-kidney connection and improve strategies for management.

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.