Norepinephrine is More Effective Than Midodrine/Octreotide in Patients With Hepatorenal Syndrome-Acute Kidney Injury: A Randomized Controlled Trial

Comparative Mortality Rates of Vasoconstrictor Agents in the Management of Hepatorenal Syndrome: A Systematic Review and Meta-Analysis

Hepatorenal syndrome (HRS) is an acute complication of advanced liver disease, which manifests with a rapidly progressive decline in kidney function. Though pharmacological treatment has been recently advanced, there are still high mortality rates. The study compares the mortality rate in patients using different vasoconstrictor agents in the management of HRS. A complete literature search was done in the following databases: PubMed, Cochrane Library, PubMed Central (PMC), and Multidisciplinary Digital Publishing Institute (MDPI). Studies were included according to previously established criteria, in which all studies reporting on adult patients with HRS treated with vasoconstrictor agents were eligible. The data extracted were analyzed with a random-effects model to express variability between studies, and the principal measure was the risk ratio (RR) for mortality. Of the 8,137 studies identified, 29 met the inclusion criteria. In the meta-analysis, vasoconstrictors, mainly terlipressin, significantly improved renal function and decreased the need for renal replacement therapy (RRT) versus placebo. However, a significant impact on mortality was lacking (0.94 (0.84-1.06), p = 0.31). The subgroup analysis found that mortality rates were not significantly different between vasoconstrictors, whether used in combination with or without albumin (0.97 (0.77-1.23), p = 0.79, and 0.98 (0.79-1.21), p = 0.86). Global heterogeneity was low, indicating consistent results in the studies. Vasoconstrictors are helpful in managing HRS, with improvement in renal function and reduction in RRT requirements. However, the effect on mortality was small and nonsignificant. Such findings support the use of terlipressin in HRS management; concomitantly, they emphasize the need for personalized treatment strategies and future research to find alternative therapies that may be more effective for improved survival results with fewer side effects.

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.

Management of hepatorenal syndrome and associated outcomes: a systematic reviews

BACKGROUND

Hepatorenal syndrome (HRS), a multiorgan condition of acute kidney injury, is seen in advanced liver disease. This study aims to evaluate the current treatment for HRS.

METHODS

The authors searched PubMed, Scopus and Google Scholar literature. After quality assessment, 31 studies were included in this review. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology and the population, intervention, comparison and outcome scheme were used. We included human-controlled trials that evaluate the current treatment for HRS. Two authors independently screened articles for inclusion, extracted data and assessed the quality of included studies.

RESULTS

This study investigated the studies conducted on the effects of different treatments on follow-up of HRS patients. We gathered 440 articles, so 31 articles remained in our study. Of which 24 articles were conducted on terlipressin versus placebo or other treatments (midodrine/octreotide, norepinephrine, etc) that showed the higher rate of HRS reversal was detected for terlipressin in 17 studies (10 of them were significant), 2 studies achieved an insignificant lower rate of the model for end-stage liver disease score for terlipressin, 15 studies showed a decreased mortality rate in the terlipressin group (4 of them were significant).

CONCLUSION

This review showed that terlipressin has a significantly higher reversal rate of HRS than the other treatments. Even the results showed that terlipressin is more efficient than midodrine/octreotide and norepinephrine as a previous medication, in reverse HRS, increasing patient survival.

Midodrine reduces new-onset acute kidney injury and hyponatremia in children with cirrhosis and ascites awaiting liver transplantation: Results from an open-label RCT

OBJECTIVES

Midodrine, an oral α-1-adrenergic receptor agonist, counters arterial hypovolemia and reduces complications in adult patients with cirrhosis. This randomized controlled trial (RCT) aimed to assess the efficacy and safety of midodrine in preventing complications and improving survival in children with cirrhosis and ascites who are awaiting liver transplantation (LT).

METHODS

This open-label RCT conducted from January 2022 to May 2023 included children under 18 years with cirrhosis and ascites. Patients were randomized to receive either midodrine plus standard medical therapies (SMTs) or SMT alone. The primary outcome measure was the incidence of cirrhosis-related complications within 6 months.

RESULTS

Thirty-five subjects were enrolled and randomized. Patients in the midodrine arm had a lower incidence of new-onset acute kidney injury (AKI) compared with the SMT arm (11.1% vs. 41.2%). Patients in the midodrine arm showed a decline in serum creatinine and improvement in glomerular filtration rate, whereas no changes were observed in the SMT arm. There was a lower incidence of new-onset hyponatremia in the midodrine arm (20% vs. 56%). Midodrine led to reduction in plasma rennin activity (PRA) and improvement in systemic hemodynamics. There was no difference in the rate of resolution of ascites, recurrence of ascites, requirement of therapeutic paracentesis, cumulative albumin infusion requirement, episodes of spontaneous bacterial peritonitis, and hepatic encephalopathy between the two arms.

CONCLUSION

Midodrine, when added to SMT, was effective in reducing the incidence of new-onset AKI and hyponatremia in pediatric cirrhotics awaiting LT. It also improved systemic hemodynamics and showed a trend towards reducing PRA.

Outcomes among patients with hepatorenal syndrome based on hospital teaching and transplant status: Analysis of 159 845 hospitalizations

Background and Aim

Hepatorenal syndrome (HRS) is a life-threatening complication of advanced liver disease. This study aimed to examine the impact of hospital teaching/transplant status and availability of liver transplantation on survival among hospitalized patients with HRS in the United States.

Methods

Patients with HRS were identified from the national inpatient sample 2016-2019. Information was collected regarding patient demographics, hospital characteristics, liver disease etiology, presence of liver disease decompensations, Elixhauser comorbidities, and interventions. Patients were classified as being treated at three hospital groups: non-teaching hospitals (NTHs), teaching non-transplant centers (TNTCs), and teaching transplant centers (TTCs). The relationship between hospital teaching/transplant status and in-hospital mortality and transplant-free mortality was examined using multivariable linear and logistic regression analysis.

Results

A total of 159,845 patients met the criteria for HRS. Of these, 24% were admitted to NTHs, 50.8% to TNTCs, and 25.2% to TTCs. Admission to a TTC was independently associated with a lower mortality risk compared to admission to non-TTCs (aOR = 0.75, 95% CI: 0.68-0.83, P <0.001). Patients at TTCs had a lower transplant-free mortality risk than those at NTHs (aOR = 0.75, 95% CI: 0.67-0.83, P < 0.001). There was no significant difference in all-cause or transplant-free mortality between TNTCs and NTHs.

Conclusion

Patients with HRS admitted to TTCs have higher disease severity, but significantly improved outcomes compared to those admitted to NTHs. These data suggest opportunities for increased disease awareness and education among NTHs and support early referral for liver transplant evaluation among hospitalized patients with HRS.

[Hepatorenal Syndrome]

Hepatorenal syndrome (HRS) is a critical and potentially life-threatening complication of advanced liver disease, including cirrhosis. It is characterized by the development of renal dysfunction in the absence of underlying structural kidney pathology. The pathophysiology of HRS involves complex interactions between systemic and renal hemodynamics, neurohormonal imbalances, and the intricate role of vasoconstrictor substances. Understanding these mechanisms is crucial for the timely identification and management of HRS. The diagnosis of HRS is primarily clinical and relies on specific criteria that consider the exclusion of other causes of renal dysfunction. The management of HRS comprises two main approaches: vasoconstrictor therapy and albumin infusion, which aim to improve renal perfusion and mitigate the hyperdynamic circulation often seen in advanced liver disease. Additionally, strategies such as liver transplantation and renal replacement therapy are essential considerations based on individual patient characteristics and disease severity. This review article provides a comprehensive overview of hepatorenal syndrome, focusing on its pathophysiology, diagnostic criteria, and current management strategies.

Acute Kidney Injury in Liver Cirrhosis

Acute kidney injury (AKI) is common in cirrhotic patients affecting almost 20% of these patients. While multiple etiologies can lead to AKI, pre-renal azotemia seems to be the most common cause of AKI. Irrespective of the cause, AKI is associated with worse survival with the poorest outcomes observed in those with hepatorenal syndrome (HRS) and acute tubular necrosis (ATN). In recent years, new definitions, and classifications of AKI in cirrhosis have emerged. More knowledge has also become available regarding the benefits and drawbacks of albumin and terlipressin use in these patients. Diagnostic tools such as urinary biomarkers and point-of-care ultrasound (POCUS) became available and they will be used in the near future to differentiate between different causes of AKI and direct management of AKI in these patients. In this update, we will review these new classifications, treatment recommendations, and diagnostic tools for AKI in cirrhotic patients.

Hepatorenal Syndrome: Pathophysiology, Diagnosis, and Treatment

Hepatorenal syndrome (HRS) is a primarily functional form of acute kidney injury (AKI) that develops in patients with decompensated cirrhosis. The pathophysiologic cascade that leads to HRS begins with pooling of blood in the splanchnic system, resulting in a decrease in effective circulating arterial volume. The definitive treatment of HRS is liver transplantation. When this is not possible, HRS is treated with a combination of vasoconstrictor agents and intravenous albumin. Although the combination of midodrine and octreotide is used in the United States, the recently approved terlipressin, an analog of vasopressin, is likely to become the first-line standard of care.

A Systematic Review of the Emerging Treatment for Hepatorenal Syndrome With a Principal Focus on Terlipressin: A Recent FDA-Approved Drug

BACKGROUND

 Hepatorenal syndrome (HRS), a consequence of liver cirrhosis, is the development of renal failure, which carries a grave prognosis. Reversing acute renal failure with various vasoconstrictor therapies at an appropriate time favors a good prognosis, especially when a liver transplant is not feasible.

OBJECTIVE

 This study aims to compare various treatment modalities to deduce an effective way to manage HRS.

METHODS

 The authors conducted a literature search in PubMed, Google Scholar, the Cochrane Library, and Science Direct in October 2022, using regular and MeSH keywords. A total of 1072 articles were identified. The PRISMA guidelines were used, the PICO framework was addressed, and the inclusion criteria were set based on studies from the past 10 years. After quality assessment, 14 studies were included for in-depth analysis in this review.  Results: A total of 14 studies were included after quality assessment, including randomized controlled trials, systematic reviews, meta-analyses, and observational cohort studies. Nine hundred and forty-one patients represented this review's experimental and observational studies, apart from the other systematic reviews analyzed. Nine studies discovered that Terlipressin, especially when administered with albumin, was more effective than other conventional treatment modalities, including norepinephrine and midodrine, in terms of improving mortality and reversing the HRS. Four studies suggested that terlipressin exhibited similar effectiveness but found no significant difference. In contrast, one study found that norepinephrine was superior to terlipressin when particularly considering the adverse effects.

CONCLUSION

 Terlipressin, one of the most widely used vasoconstrictor agents across the world, seems to be effective in reversing renal failure in HRS. Although adverse effects are seen with this agent, it is still beneficial when compared to other medications. Further studies with larger sample sizes may be warranted.

Responsiveness to Vasoconstrictor Therapy in Hepatorenal Syndrome Type 1

Key Points

Raising the mean arterial pressure (MAP) during management of hepatorenal syndrome type 1 (HRS-1) is associated with improvement in kidney function, independently of baseline MAP or model for end-stage liver disease. Raising the MAP by 15 mm Hg or greater leads to greater reduction in serum creatinine in HRS-1. Norepinephrine use confers greater probability of improvement in kidney function in HRS-1 compared with midodrine/octreotide.

Background

Raising mean arterial pressure (MAP) during treatment of hepatorenal syndrome type 1 (HRS-1) with vasoconstrictors (VCs) is associated with renal recovery. However, the optimal MAP target and factors associated with response to VCs remain unclear.

Methods

Records from hospitalized patients with HRS-1 treated with VCs without shock were reviewed searching for those who achieved ≥5 mm Hg rise in MAP within 48 hours. We examined the relationship between the mean MAP achieved during the first 48–72 hours of VC therapy and the change in serum creatinine (sCr) up to day 14. Endpoints were >30% reduction in sCr without need for dialysis or death by day 14 (primary) or by day 30 (secondary).

Results

Seventy-seven patients with HRS-1 treated for 2–10 days with either norepinephrine (n =49) or midodrine/octreotide (n =28) were included. The median age was 52 years (interquartile range [IQR], 46–60), 40% were female, and 48% had alcoholic cirrhosis. At VC initiation, median MAP was 70 mm Hg (IQR, 66–73), and median sCr was 3.8 mg/dl (IQR, 2.6–4.9). When analyzed by tertiles of mean MAP increment (5–9, 10–14, ≥15 mm Hg), there was greater reduction in sCr with greater rise in MAP (ANOVA for trend, P < 0.0001). By multivariate logistic regression analysis, mean MAP rise during the first 48–72 hours (odds ratio [OR], 1.15 [1.02 to 1.299], P =0.025), norepinephrine as VC (OR, 5.46 [1.36 to 21.86], P =0.017), and baseline sCr [OR, 0.63 [0.41 to 0.97], P =0.034) were associated with the primary endpoint, whereas mean MAP rise during the first 48–72 hours (OR, 1.17 [1.04 to 1.33], P =0.012) and baseline sCr (OR, 0.63 [0.39 to 0.98], P =0.043) were associated with the secondary endpoint.

Conclusions

Greater magnitude of rise in MAP with VC therapy in HRS-1, lower baseline sCr, and use of norepinephrine over midodrine/octreotide are associated with kidney recovery. Targeting an increment of MAP ≥15 mm Hg may lead to favorable renal outcomes.

Vasoconstrictor Therapy for Acute Kidney Injury Hepatorenal Syndrome: A Meta-Analysis of Randomized Studies

Background and Aims

Type 1 hepatorenal syndrome (HRS) is a rapid deterioration in kidney function in patients with cirrhosis. Data on efficacy of vasoconstrictors for type 1 HRS have shown mixed results.

Methods

Literature searched for randomized controlled trials comparing pharmacological therapy for HRS vs placebo or another drug for HRS. Primary outcome was HRS reversal (serum creatinine <1.5mg/dL on 2 readings), and secondary outcomes were liver transplant (LT) free survival and serious adverse events (SAE).

Results

Sixteen studies on 1244 patients (mean age 50.3 yrs., 67.5% males, serum creatinine of 3.07 mg/dL, serum sodium 127.2 mEq/liter, and Model for End-stage Liver Disease (MELD) score of 30.9, and Child-Pugh score 11) with type 1 HRS treated with vasoconstrictors vs placebo or another drug were analyzed. All the patients received intravenous albumin infusion. (A) terlipressin vs placebo: Odds of HRS reversal were 3.3 folds with terlipressin without difference on LT-free patient survival. Terlipressin was associated with higher odds of SAE. (B) Nor-epinephrine (NE) vs terlipressin: No difference on HRS reversal, LT-free survival, and SAE. (C) Terlipressin or NE vs midodrine and octreotide: 91% lower odds of HRS reversal with midodrine and octreotide. There were no differences on SAE (10 of 64 vs 10 of 58, P = .812). Non-responders vs responders had higher mean MELD score (29 vs 27.8), P = .014 and serum creatinine (3.5 vs 3.1), P = .027.

Conclusion

Terlipressin and NE are similar and superior to midodrine octreotide combination for HRS reversal. No therapy improves LT-free patient survival. Response to treatment is better with lower baseline serum creatinine and MELD score. The risk of adverse effects is similar with terlipressin and NE. Studies are needed as basis to identify candidates with best response to treatment with excellent safety profile.

Cost-effectiveness of terlipressin for hepatorenal syndrome: the United States hospital perspective

BACKGROUND

Hepatorenal syndrome (HRS) is characterized by severely reduced renal perfusion that precipitates rapid morbidity and mortality. Terlipressin is the only US Food and Drug Administration-approved treatment to improve kidney function for adults with HRS with a rapid reduction in kidney function. Prior to the approval of terlipressin, unapproved vasoconstrictive agents used in HRS treatment were octreotide/midodrine and norepinephrine with albumin.

METHODS

A cohort decision-tree model representing a US hospital perspective assessed the clinical outcomes and direct medical costs (based primarily on hospital charges) of treating HRS with terlipressin + albumin (ALB) versus midodrine/octreotide (MID/OCT)+ALB, or norepinephrine (NorEp)+ALB. Treatment efficacy was defined by clinical response (complete/HRS reversal, partial, or no response) based on change of serum creatinine derived from published clinical trial reports. The proportions of patients with complete response were: terlipressin + ALB (36.2%), NorEp + ALB (19.1%), and MID/OCT + ALB (3.1%). Model outcomes included utilization of HRS-related healthcare resources (hospital and intensive care, outpatient and emergency department, dialysis, and transplantations), adverse events, and HRS-related mortality. Outcomes were assessed for the initial hospitalization in the base case and at 30, 60, and 90 days post-discharge.

RESULTS

Total costs incurred over the initial hospitalization with terlipressin + ALB were lower vs NorEp + ALB, primarily due to higher ICU costs with NorEp + ALB ($7,433 vs $61,897). TER + ALB was associated with higher total costs vs MID/OCT + ALB due to higher pharmacy costs with terlipressin + ALB. The cost per complete response achieved of terlipressin + ALB ($451,605) was half that of NorEp + ALB ($930,571) and one-tenth that of MID/OCT + ALB ($4,942,123).

CONCLUSIONS

HRS patients treated with terlipressin experienced better clinical outcomes and a lower cost per treatment response vs other unapproved treatments. ICU days and pharmacy costs were key cost drivers distinguishing the treatment groups. These outcomes suggest that terlipressin is cost-effective on the basis of total cost per response achieved.

Spontaneous peritoneal drainage following paracentesis in a hospitalized patient with resolution of type 1 hepatorenal syndrome

The hepatorenal syndrome develops in a small percentage of patients with advanced liver disease. The pathogenesis involves intravascular volume contraction secondary to pooling of blood in the splanchnic vessels, stimulation of the sympathetic nervous system and the renin-angiotensin-aldosterone pathway, and increased intra-abdominal pressure secondary to the formation of large volumes of ascitic fluid. The treatment options are limited, and liver transplant is the only definitive form of management. Here we suggest an alternative approach to treating hepatorenal syndrome based on the unexpected continuous peritoneal drainage in a 36-year-old man hospitalized with hepatic encephalopathy and hepatorenal syndrome. A total of 11.2 L ascitic fluid drained over 5 days from a paracentesis puncture site with marked improvement in renal function; the creatinine decreased from 3.3 mg/dL to 0.7 mg/dL and the BUN decreased from 42 mg/dL to 10 mg/dL. The discussion with this case report summarizes the pathogenesis, including the effect of intra-abdominal pressure, of the hepatorenal syndrome, outlines medical management, and makes a proposal for clinical study based on this case.

Acute Kidney Injury in Patients with Liver Disease

AKI is commonly encountered in patients with decompensated cirrhosis, and it is associated with unfavorable outcomes. Among factors specific to cirrhosis, hepatorenal syndrome type 1, also referred to as hepatorenal syndrome-AKI, is the most salient and unique etiology. Patients with cirrhosis are vulnerable to traditional causes of AKI, such as prerenal azotemia, acute tubular injury, and acute interstitial nephritis. In addition, other less common etiologies of AKI specifically related to chronic liver disease should be considered, including abdominal compartment syndrome, cardiorenal processes linked to cirrhotic cardiomyopathy and portopulmonary hypertension, and cholemic nephropathy. Furthermore, certain types of GN can cause AKI in cirrhosis, such as IgA nephropathy or viral hepatitis related. Therefore, a comprehensive diagnostic approach is needed to evaluate patients with cirrhosis presenting with AKI. Management should be tailored to the specific underlying etiology. Albumin-based volume resuscitation is recommended in prerenal AKI. Acute tubular injury and acute interstitial nephritis are managed with supportive care, withdrawal of the offending agent, and, potentially, corticosteroids in acute interstitial nephritis. Short of liver transplantation, vasoconstrictor therapy is the primary treatment for hepatorenal syndrome type 1. Timing of initiation of vasoconstrictors, the rise in mean arterial pressure, and the degree of cholestasis are among the factors that determine vasoconstrictor responsiveness. Large-volume paracentesis and diuretics are indicated to relieve intra-abdominal hypertension and renal vein congestion. Direct-acting antivirals with or without immunosuppression are used to treat hepatitis B/C-associated GN. In summary, AKI in cirrhosis requires careful consideration of multiple potentially pathogenic factors and the implementation of targeted therapeutic interventions.

Mastering Core Recommendations during HEPAtology ROUNDS in Patients with Advanced Chronic Liver Disease

Efficient and thorough care of hospitalized patients with advanced chronic liver disease is of utter importance to improve outcomes and optimize quality of life. This requires understanding current evidence and best practices. To facilitate focus on up-to-date knowledge and a practical approach, we have created the HEPA-ROUNDS mnemonic while outlining a practical review of the literature with critical appraisal for the busy clinician. The HEPA-ROUNDS mnemonic provides a structured approach that incorporates critical concepts in terms of prevention, management, and prognostication of the most common complications frequently encountered in patients with advanced chronic liver disease. In addition, implementing the HEPA-ROUNDS mnemonic can facilitate education for trainees and staff caring for patients with advanced chronic liver disease.

The Comparative Effectiveness of Vasoactive Treatments for Hepatorenal Syndrome: A Systematic Review and Network Meta-Analysis

OBJECTIVE

Hepatorenal syndrome (HRS) is associated with high rates of morbidity and mortality. Evidence examining commonly used drug treatments remains uncertain. We assessed the comparative effectiveness of inpatient treatments for HRS by performing a network meta-analysis of randomized clinical trials (RCTs).

DATA SOURCES

We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Medline In-Process & Other Non-Indexed Citations, Scopus, and Web of Science from inception.

STUDY SELECTION AND DATA EXTRACTION

Pairs of reviewers independently identified eligible RCTs that enrolled patients with type 1 or 2 HRS. Pairs of reviewers independently extracted data.

DATA SYNTHESIS

We assessed risk of bias using the Cochrane tool for RCTs and certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluations approach. Our main outcomes are all-cause mortality, HRS reversal, and serious adverse events. Of 3,079 citations, we included 26 RCTs examining 1,736 patients. Based on pooled analysis, terlipressin increases HRS reversal compared with placebo (142 reversals per 1,000 [95% CI, >87.7 to >210.9]; high certainty). Norepinephrine (112.7 reversals per 1,000 [95% CI, 52.6 to >192.3]) may increase HRS reversal compared with placebo (low certainty). The effect of midodrine+octreotide (67.8 reversals per 1,000 [95% CI, <2.8 to >177.4]; very low) on HRS reversal is uncertain. Terlipressin may reduce mortality compared with placebo (93.7 fewer deaths [95% CI, 168.7 to <12.5]; low certainty). Terlipressin probably increases the risk of serious adverse events compared with placebo (20.4 more events per 1,000 [95% CI, <5.1 to >51]; moderate certainty).

CONCLUSIONS

Terlipressin increases HRS reversal compared with placebo. Terlipressin may reduce mortality. Until access to terlipressin improves, initial norepinephrine administration may be more appropriate than initial trial with midodrine+octreotide. Our review has the potential to inform future guideline and practice in the treatment of HRS.

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.

Hepatorenal Syndrome: Definitions, Diagnosis, and Management

Hepatorenal syndrome (HRS) is a hemodynamically driven process mediated by renal dysregulation and inflammatory response. Albumin, antibiotics, and β-blockers are among therapies that have been studied in HRS prevention. There are no Food and Drug Administration-approved treatments for HRS although multiple liver societies have recommended terlipressin as first-line pharmacotherapy. Renal replacement therapy is the primary modality used to bridge to definitive therapy with orthotopic liver transplant or simultaneous liver-kidney transplant. Advances in our understanding of HRS pathophysiology and emerging therapeutic modalities are needed to change outcomes for this vulnerable population.

Hepatorenal Syndrome Type 1: From Diagnosis Ascertainment to Goal-Oriented Pharmacologic Therapy

Hepatorenal syndrome type 1 (HRS-1) is a serious form of AKI that affects individuals with advanced cirrhosis with ascites. Prompt and accurate diagnosis is essential for effective implementation of therapeutic measures that can favorably alter its clinical course. Despite decades of investigation, HRS-1 continues to be primarily a diagnosis of exclusion. Although the diagnostic criteria dictated by the International Club of Ascites provide a useful framework to approach the diagnosis of HRS-1, they do not fully reflect the complexity of clinical scenarios that is often encountered in patients with cirrhosis and AKI. Thus, diagnostic uncertainty is often faced. In particular, the distinction between HRS-1 and acute tubular injury is challenging with the currently available clinical tools. Because treatment of HRS-1 differs from that of acute tubular injury, distinguishing these two causes of AKI has direct implications in management. Therefore, the use of the International Club of Ascites criteria should be enhanced with a more individualized approach and attention to the other phenotypic aspects of HRS-1 and other types of AKI. Liver transplantation is the most effective treatment for HRS-1, but it is only available to a small fraction of the affected patients worldwide. Thus, pharmacologic therapy is necessary. Vasoconstrictors aimed to increase mean arterial pressure constitute the most effective approach. Administration of intravenous albumin is an established co-adjuvant therapy. However, the risk for fluid overload in patients with cirrhosis with AKI is not negligible, and interventions intended to expand or remove volume should be tailored to the specific needs of the patient. Norepinephrine and terlipressin are the most effective vasoconstrictors, and their use should be determined by availability, ease of administration, and attention to optimal risk-benefit balance for each clinical scenario.

Terlipressin and the Treatment of Hepatorenal Syndrome: How the CONFIRM Trial Moves the Story Forward

Hepatorenal syndrome (HRS) is a form of acute kidney injury occurring in patients with advanced cirrhosis and is associated with significant morbidity and mortality. The pathophysiology underlying HRS begins with increasing portal pressures leading to the release of vasodilatory substances which result in pooling blood in the splanchnic system and a corresponding reduction in effective circulating volume. Compensatory activation of the sympathetic nervous system, renin-angiotensin-aldosterone system and release of arginine vasopressin serve to defend mean arterial pressure but at the cost of severe constriction of the renal vasculature, leading to a progressive, often fulminant form of AKI. While there are no approved treatments for HRS in the United States, multiple countries, including much of Europe, utilize terlipressin, a synthetic vasopressin analogue, as first-line therapy. The recently published CONFIRM trial, the third randomized trial based in North America evaluating terlipressin, met its primary endpoint, showing greater rates of HRS reversal in the terlipressin arm. However, due to concerns about apparent increased rates of respiratory adverse events and a lack of evidence for mortality benefit, terlipressin was not approved by the Food and Drug Administration (FDA). In this Perspective, we explore the history of regulatory approval for terlipressin in the United States, examine the results from CONFIRM and the concerns they raised and consider the future role of terlipressin in this critical clinical area of continued unmet need.