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.

Markers of cell death predict therapy response in patients with cirrhosis and hepatorenal syndrome.

BACKGROUND AND AIMS: Hepatorenal syndrome is a major complication in patients with cirrhosis and associated with high mortality. Predictive biomarkers for therapy response are largely missing. Cytokeratin18-based cell death markers are significantly elevated in patients with complications of chronic liver disease, but the role of these markers in patients with HRS treated with vasoconstrictors and albumin is unknown. METHODS: We prospectively analyzed a total of 138 patients with HRS, liver cirrhosis without HRS and acute kidney injury treated at the University Medical Center Mainz between April 2013 and July 2018. Serum levels of M30 and M65 were analyzed by ELISA and clinical data were collected. Predictive ability was assessed by Kaplan-Meier curves, logistic regression and c-statistic. Primary endpoint was response to therapy. RESULTS: M30 and M65 were significantly increased in patients with HRS compared to non-HRS controls (M30: p < 0.0001; M65: p < 0.0001). Both serum markers showed predictive ability for dialysis- and LTX-free survival but not overall survival. Logistic regression confirmed M30 and M65 as independent prognostic factors for response to therapy. A novel predictive score comprising bilirubin and M65 showed highest predictive ability to predict therapy response. CONCLUSIONS: Serum levels of M30 and M65 can robustly discriminate patients into responders and non-responders to terlipressin therapy with a good predictive ability for dialysis- and LTX-free survival in cirrhotic patients. Cell death parameters might possess clinical relevance in patients with liver cirrhosis and HRS.

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.

Improvement of renal function prior to liver transplantation is not associated with better long-term renal outcome or survival.

INTRODUCTION AND OBJECTIVES: Since MELD implementation renal impairment in liver transplant (LT) recipients has become of increasing importance. This is the first study evaluating the course of renal function immediately prior to LT as predictor for long-term renal and overall outcome. PATIENTS AND METHODS: In this retrospective study, 226 adults undergoing LT at the University Medical Center Hamburg-Eppendorf (2011-2015) were included. The impact of renal function over a period of 3 months prior to LT compared to renal function at the day of LT on long-term renal outcome and survival was assessed. RESULTS: According to GFR at day of LT renal function improved (≥1 CKD stage) in 64 patients (28%), remained stable in 144 (64%) or deteriorated in 18 (8%). Improvement of renal function prior to LT did neither significantly affect 90-day (13% vs. 14%, p = 0.83), nor 5-year post-LT mortality (35% vs. 41%, p = 0.57). 50 patients (22%) with hepatorenal syndrome (HRS) received terlipressin prior to LT, but only 18 (37%) showed prolonged stabilization of renal function (improvement ≥1 CKD stage). Response to terlipressin did neither improve 90-day (p=1), 5-year mortality (p = 0.52) nor long-term renal function (p = 0.843). Nevertheless, need for dialysis pre-LT (59% vs. 34%, p = 0.005) and post-LT (62% vs. 17%, p<0.001) was associated with increased 5-year mortality. CONCLUSIONS: Improvement of renal function immediately prior to LT, either spontaneously or following terlipressin therapy, did neither ameliorate long-term renal outcome nor survival in LT recipients. Future studies need to clarify the impact of terlipressin in HRS on the transplant waiting time in LT candidates.

Hepatorenal syndrome: pathophysiology and evidence-based management update.

Hepatorenal syndrome (HRS) is a functional renal failure that develops in patients with advanced hepatic cirrhosis with ascites and in those with fulminant hepatic failure. The prevalence of HRS varies among studies but in general it is the third most common cause of acute kidney injury (AKI) in cirrhotic patients after pre-renal azotemia and acute tubular necrosis. HRS carries a grim prognosis with a mortality rate approaching 90% three months after disease diagnosis. Fortunately, different strategies have been proven to be successful in preventing HRS. Although treatment options are available, they are not universally effective in restoring renal function but they might prolong survival long enough for liver transplantation, which is the ultimate treatment. Much has been learned in the last two decades regarding the pathophysiology and management of this disease which lead to notable evolution in the HRS definition and better understanding on how best to manage HRS patients. In the current review, we will summarize the recent advancement in epidemiology, pathophysiology, and management of HRS.

The Use of Rifaximin in Patients With Cirrhosis.

Rifaximin is an oral nonsystemic antibiotic with minimal gastrointestinal absorption and broad-spectrum antibacterial activity covering both gram-positive and gram-negative organisms. Rifaximin is currently used worldwide in patients with cirrhosis for preventing recurrent HE because its efficacy and safety have been proven by large randomized clinical trials. In the last decade, experimental and clinical evidence suggest that rifaximin could have other beneficial effects on the course of cirrhosis by modulating the gut microbiome and affecting the gut-liver axis, which in turn can interfere with major events of the pathophysiological cascade underlying decompensated cirrhosis, such as systemic inflammatory syndrome, portal hypertension, and bacterial infections. However, the use of rifaximin for prevention or treatment of other complications, including spontaneous bacterial peritonitis or other bacterial infections, is not accepted because evidence by clinical trials is still very weak. The present review deals in the first part with the potential impact of rifaximin on pathogenic mechanisms in liver diseases, whereas in the second part, its clinical effects are critically discussed. It clearly emerges that, because of its potential activity on multiple pathogenic events, the efficacy of rifaximin in the prevention or management of complications other than HE deserves to be investigated extensively. The results of double-blinded, adequately powered randomized clinical trials assessing the effect of rifaximin, alone or in combination with other drugs, on hard clinical endpoints, such as decompensation of cirrhosis, acute-on-chronic liver failure, and mortality, are therefore eagerly awaited.

Hyponatremia in Cirrhosis: An Update.

Hyponatremia is frequently seen in patients with ascites secondary to advanced cirrhosis and portal hypertension. Although not apparent in the early stages of cirrhosis, the progression of cirrhosis and portal hypertension leads to splanchnic vasodilation, and this leads to the activation of compensatory mechanisms such as renin-angiotensin-aldosterone system (RAAS), sympathetic nervous system, and antidiuretic hormone (ADH) to ameliorate low circulatory volume. The net effect is the avid retention of sodium and water to compensate for the low effective circulatory volume, resulting in the development of ascites. These compensatory mechanisms lead to impairment of the kidneys to eliminate solute-free water in decompensated cirrhosis. Nonosmotic secretion of antidiuretic hormone (ADH), also known as arginine vasopressin, further worsens excess water retention and thereby hyponatremia. The management of hyponatremia in this setting is a challenge as conventional therapies for hyponatremia including fluid restriction and correction of hypokalemia are frequently inefficacious. In this review, we discuss the pathophysiology, complications, and various treatment modalities, including albumin infusion, selective vasopressin receptor antagonists, or hypertonic saline for patients with severe hyponatremia and those awaiting liver transplantation.

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.

[Paradigm shift in understanding Acute kidney injury in patients with chronic liver disease: From pathophysiology to defining disease entities]. / Paradigmenwechsel im Verständnis der akuten Nierenschädigung bei chronischer Leberinsuffizienz: Von der Pathophysiologie zur Definition von Krankheitsentitäten.

The hepatorenal syndrome (HRS) is only a part of the wide spectrum of renal injury in patients with end-stage liver cirrhosis. Besides that, the advanced liver disease itself, or its underlying causes, as well as comorbidities, like diabetes mellitus, adiposity and arterial hypertension, can directly cause parenchymal renal insults (bile acid nephropathy, ischemic tubular injury, diabetic/hypertensive nephropathy, hepatitis B- and C-associated glomerulonephritis etc.). This kind of kidney injury is collectively described as non-hepatorenal syndrome AKI (non-HRS AKI. Beyond that, accumulating evidence highlights the role of systemic inflammation as an important common factor in the pathogenesis of decompensated liver cirrhosis, acute in chronic liver failure (ACLF) and renal dysfunction.In this review, we discuss recent data about definition, classification and pathophysiology of HRS, HRS-AKI and Non-HRS-AKI and exploit in this regard the diagnostic and prognostic potential of respective newer serum and urine markers.

Intervention on Spontaneous Splenorenal Shunt May Decrease the Incidence of Acute Kidney Injury After Liver Transplant.

OBJECTIVES: Spontaneous splenorenal shuntis a type of portosystemic shunt that develops frequently in the setting of chronic portal hypertension. It remains controversial whether shuntinterventions during liver transplant improve transplant outcomes. MATERIALS AND METHODS: We conducted a retrospective comparison between deceased-donor liver transplant recipients who received spontaneous splenorenal shunt intervention and those who did not at a tertiary center between 2012 and 2017. Primary outcomes of interest included intraoperative transfusion requirement, hospital length of stay, acute kidney injury posttransplant, portal vein thrombosis, thrombocytopenia, and 1-year graft and patient survival. RESULTS: Of 268 liver transplant recipients, 50 (18.6%) had large spontaneous splenorenal shunts pretransplant, with 45 patients having available radiologic and outcome data. Nine of 45 patients (20%) received shunt intervention, including pretransplant balloonoccluded retrograde transvenous obliteration (n = 5), intraoperative ligation of the left renal vein (n = 3), and intraoperative direct shunt ligation (n = 1). Demographic data, clinical characteristics, and Model for End-Stage Liver Disease scores were not different between the intervention and the nonintervention groups. Intraoperative transfusion, length of hospitalization, portal vein thrombosis, thrombocytopenia, and 1-year graft and patient survival were also similar between the 2 groups. However, the rate of posttransplant acute kidney injury was significantly lower in patients in the intervention group (0 cases vs 12 cases; odds ratio = 0.73; 95% confidence interval, 0.59-0.90). Patients with no SRS intervention (n = 36) were followed radiologically for 1 year posttransplant, with follow-up data showing complete resolution of spontaneous splenorenal shunt in just 4 patients (15%) and no changes in the remaining patients. CONCLUSIONS: Peritransplant interventions for spontaneous splenorenal shunt may reduce posttransplant acute kidney injury. In patients without intervention, spontaneous splenorenal shunt predominantly persisted 1 year posttransplant.

Diagnosis and management of renal dysfunction in patients with cirrhosis.

Introduction: Renal dysfunction commonly occurs in patients with cirrhosis and is typically associated with poor prognosis. Several pathophysiologic mechanisms are responsible for renal disease in these patients, prompt identification permits individualized management.Areas covered: Pathophysiology, evaluation and differential diagnosis, management and prognosis of renal disease in patients with cirrhosis. Special focus on management of hepatorenal syndrome and indications for simultaneous liver-kidney transplantation.Literature search methodology: a detailed literature search was performed using PubMed without date restrictions. Published guidelines and position papers were also used and cross-referenced to identify additional studies.Expert opinion: The prognostic significance of renal dysfunction in patients with cirrhosis is highlighted by the inclusion of serum creatinine in the model for end-stage liver disease (MELD). Both acute and chronic renal dysfunction result in increased mortality in patients with cirrhosis, although there are marked differences related to the etiology of renal disease. Early recognition and prompt intervention determined by the most likely etiology are key in the management of these patients. Simultaneous liver-kidney transplantation improves patient survival compared to isolated liver transplantation in patients with cirrhosis and persistent renal impairment; however, selection of candidates must be judicious and individualized due to the ongoing shortage of donor kidneys.

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.

News in pathophysiology, definition and classification of hepatorenal syndrome: A step beyond the International Club of Ascites (ICA) consensus document.

Renal dysfunction is a common, life-threatening complication occurring in patients with liver disease. Hepatorenal syndrome (HRS) has been defined as a purely "functional" type of renal failure that often occurs in patients with cirrhosis in the setting of marked abnormalities in arterial circulation, as well as overactivity of the endogenous vasoactive systems.4,5 In 2007, the International Club of Ascites (ICA) classified HRS into types 1 and 2 (HRS-1 and HRS-2).5 HRS-1 is characterised by a rapid deterioration of renal function that often occurs because of a precipitating event, while HRS-2 is a moderate and stable or slowly progressive renal dysfunction that often occurs without an obvious precipitant. Clinically, HRS-1 is characterised by acute renal failure while HRS-2 is mainly characterised by refractory ascites. Nevertheless, after these two entities were first described, new concepts, definitions, and diagnostic criteria have been developed by nephrologists for renal dysfunction in the general population and hospitalised patients. In particular, the definitions and characterisation of acute kidney injury (AKI), acute kidney disease and chronic kidney disease have been introduced/refined.6 Accordingly, a debate among hepatologists of the ICA led to a complete revision of the nomenclature and diagnosistic criteria for HRS-1, which was renamed HRS-AKI.7 Additionally, over recent years, greater granularity has been gained regarding the pathogenesis of HRS; it is now increasingly recognised that it is not a purely "functional" entity with haemodynamic derangements, but that systemic inflammation, oxidative stress and bile salt-related tubular damage may contribute significantly to its development. That is, HRS has an additional structural component that would not only make traditional diagnostic criteria less reliable, but would explain the lack of response to pharmacological treatment with vasoconstrictors plus albumin that correlates with a progressive increase in inflammation. Because classification, nomenclature, diagnostic criteria and pathogenic theories have evolved over the years since the traditional classification of HRS-1 and HRS-2 was first described, it was considered that all these novel aspects be reviewed and summarised in a position paper. The aim of this position paper authored by two hepatologists (members of ICA) and two nephrologists involved in the study of renal dysfunction in cirrhosis, is to complete the re-classification of HRS initiated by the ICA in 2012 and to provide an update on the definition, classification, diagnosis, pathophysiology and treatment of HRS.

High versus low mean arterial pressures in hepatorenal syndrome: A randomized controlled pilot trial.

There is controversy regarding the mean arterial pressure (MAP) goals that should be targeted in the treatment of hepatorenal syndrome (HRS.) We conducted a study to assess different MAP targets in HRS in the intensive care unit (ICU). MATERIALS AND METHODS: This is a prospective randomized controlled pilot trial. ICU patients had target mean arterial pressure (MAP) ≥ 85 mmHg (control arm) or 65-70 mmHg (study arm). Urine output and serum creatinine were trended and recorded. RESULTS: A total of 18 patients were enrolled. The day four urine output in the high and low MAP group was 1194 (SD = 1249) mL/24 h and 920 (SD = 812) mL/24 h, respectively. The difference in day four - day one urine output was -689 (SD = 1684) mL/24 h and 272 (SD = 582) mL/24 h for the high and low MAP groups. The difference in serum creatinine at day four - day one was -0.54 (SD = 0.63) mg/dL and - 0.77 (SD = 1.14) mg/dL in the high and low MAP groups, respectively. CONCLUSION: In this study, we failed to prove non-inferiority between a low and high target MAP in patients with HRS. TRIAL REGISTRATION: This trial was registered with and approved by the University of Louisville Internal Review Board and hospital research review committees (IRB # 14.1190). The trial was registered with ClinicalTrials.gov (ID # NCT02789150). The IRB committee roster 7/21/2014-2/26/2015 is registered with IORG (IORG # IORG0000147; OMB # 0990-0279) and is available at http://louisville.edu/research/humansubjects/about-the-irb/rosters/RosterEffective20140721thru20150226.pdf.

Vasoconstrictors in hepatorenal syndrome - A critical review.

Hepatorenal syndrome has the worst prognosis among causes of acute kidney injury in cirrhotic patients. Its definitive treatment is liver transplantation. Nevertheless, considering its high short-term mortality rate and the shortage of liver grafts, a pharmacological treatment is of utmost importance, serving as a bridge to liver transplant. The clinical management of hepatorenal syndrome is currently based on the use of a vasoconstrictor in association with albumin. Terlipressin, noradrenaline and the combination of midodrine and octreotide could be used to treat hepatorenal syndrome. Among these options, terlipressin seems to gather the strongest body of evidence regarding efficacy and should be considered the first line of treatment whenever available and in the absence of contraindications. Treatment with a vasoconstrictor and albumin should be promptly initiated after the diagnosis of hepatorenal syndrome in order for patients to have higher chances of recovery.

Vascular syndromes in liver cirrhosis.

Liver cirrhosis is associated with multiple vascular syndromes affecting almost all body systems. Many of these syndromes are directly related to impaired liver function and sometimes reversible after liver transplantation while others arise secondary to portal hypertension and ascites. Altered expression of angiogenic and vasoactive compounds (most importantly nitric oxide), endothelial dysfunction, dysregulated neurohormonal control, and systemic inflammatory state play differential roles in mediating homeostatic instability and abnormal vasogenic response. Important vascular features encountered in liver disease include portal hypertension, splanchnic overflow, abnormal angiogenesis and shunts, portopulmonary syndrome, hepatopulmonary syndrome, and systemic hyperdynamic circulation. Redistribution of effective circulatory volume deviating from vital organs and pooling in splanchnic circulation is also encountered in liver patients which may lead to devastating outcomes as hepatorenal syndrome. Etiologically, vascular syndromes are not isolated phenomena and vascular dysfunction in one system may lead to the development of another in a different system. This review focuses on understanding the pathophysiological factors underlying vascular syndromes related to chronic liver disease and the potential links among them. Many of these syndromes are associated with high mortality, thus it is crucial to look for early biomarkers for these syndromes and develop novel preventive and therapeutic strategies.

Arritmias e alterações cardíacas no paciente cirrótico / Arrhythmias and cardiac alterations in the cirrhotic patient

No Brasil, a cirrose é um problema de saúde pública, que afeta aproximadamente 2 milhões de pessoas. As causas mais comuns são a doença hepática alcoólica, as hepatites virais e a doença hepática não alcoólica. A relação entre desordens cardíacas e hepatopatias é descrita na literatura, e a mais importante delas é o prolongamento do intervalo QT. A cirrose, independente de sua causa, é uma patologia frequentemente encontrada na população brasileira. Por este motivo, elucidar dados referentes às arritmias cardíacas em pacientes cirróticos é de grande importância dentro do estudo desta subpopulação. O objetivo deste artigo é fazer uma revisão de literatura com as informações referentes a epidemiologia, fisiopatologia, fatores de risco e prognóstico para as arritmias cardíacas em portadores de cirrose. (AU)

In Brazil, cirrhosis is a public health problem affecting approximately 2 million people. The most common causes are alcoholic liver disease, viral hepatitis, and non-alcoholic liver disease. The relationship between cardiac disorders and liver diseases is described in the literature, and the most important one is the QT interval prolongation. Cirrhosis, regardless of its causes, is a pathology that is frequently found in the Brazilian population. For this reason, elucidating data regarding cardiac arrhythmias in cirrhotic patients is of great importance within the study of this subpopulation. The aim of this article is to review the literature with information on the epidemiology, pathophysiology, risk factors, and prognosis for cardiac arrhythmias in patients with cirrhosis. (AU)

The burden of illness of hepatorenal syndrome (HRS) in the United States: a retrospective analysis of electronic health records.

OBJECTIVES: Hepatorenal Syndrome (HRS) is characterized by renal failure in patients with advanced chronic liver disease (CLD) and is the leading cause of hospitalizations in CLD. This study examines the clinical and economic burden, outcomes, and unmet need of HRS treatment in US hospitals. METHOD: A retrospective cohort study was conducted based on a large electronic health records database (Cerner HealthFacts) with records for hospitalized HRS patients from January 2009-June 2015. Demographics, clinical characteristics, treatment patterns, and economic outcomes were analyzed. Prognostic indicators of cirrhosis, kidney injury, end-stage liver disease, and acute-on-chronic liver failure were used to determine mortality risk. RESULTS: A total of 2,542 patients hospitalized with HRS were identified (average age = 57.9 years, 61.8% males, 74.2% Caucasian), with an average total hospital charge of $91,504 per patient and a mean length of stay (LOS) of 30.5 days. The mortality rate was 36.9% with 8.9% of patients discharged to hospice. Of all patients, 1,660 patients had acute kidney injury, 859 with Stage 3 disease, and 26.7% had dialysis. The 30-day readmission rate was 33.1%, 41% of which were unplanned. Nearly one-third of study patients had commercial insurance (30.2%), followed by Medicare (29.9%); hospital charges varied by LOS, receipt of dialysis, and discharge status. Regression analysis demonstrated that HRS costs are associated with LOS, dialysis, and hospital mortality. CONCLUSION: HRS is associated with poor outcomes and high hospital costs. Analysis of HRS cost drivers demonstrated an unmet need for additional treatment options to improve outcomes in this patient population.

Epidemiology, Pathophysiology, and Management of Hepatorenal Syndrome.

Acute kidney injury (AKI) is a common presentation in patients with advanced cirrhosis hospitalized with acute decompensation. A new revised classification now divides AKI in cirrhotic patients into two broad subgroups: hepatorenal syndrome AKI (HRS AKI) and non-hepatorenal syndrome AKI (non-HRS AKI). HRS AKI represents the end-stage complication of decompensated cirrhosis with severe portal hypertension and is characterized by worsening of renal function in the absence of prerenal azotemia, nephrotoxicity, and intrinsic renal disease. Non-HRS AKI may be caused by prerenal hypoperfusion, bile acid nephropathy, nephrotoxicity, or acute parenchymal insult. There have been several mechanisms proposed to explain the pathophysiology of HRS AKI and non-HRS AKI, and a number of biomarkers have been suggested to aid in differentiation between these types of AKI and to act as prognostic indicators. The standard of care clinical management for patients with HRS AKI is to exclude other etiologies of AKI, followed by volume expansion with human albumin solution and then the introduction of vasopressors. However, some 40% of patients treated for HRS AKI fail to respond. In this review, we discuss the current and recent data about classification, pathophysiology, and management of AKI in general, with specific insight about the treatment of HRS AKI.