Determination of Effective Albumin in Patients With Decompensated Cirrhosis: Clinical and Prognostic Implications

Association between lactate-to-albumin ratio and short-term prognosis of acute-on-chronic liver failure treated with artificial liver support system

BACKGROUND

The impact of lactate-to-albumin ratio (LAR) on the outcome of acute-on-chronic liver failure (ACLF) is scant.

AIMS

To investigate the relationship between LAR and short-term prognosis in patients with COSSH (Chinese Group on the Study of Severe Hepatitis B) ACLF.

METHODS

A retrospective cohort study was conducted in patients with COSSH ACLF treated with an artificial liver support system. Restricted cubic splines, linear regression models, and Cox regression models were used to investigate the relationships of LAR with disease severity and 28-day prognosis.

RESULTS

The 28-day transplant-free and overall survival rates in the 258 eligible patients were 76.4% and 82.2%, respectively. The LAR in 28-day transplant-free survivors was lower than that in transplant or death patients [0.74 (0.58-0.98) vs. 1.03 (0.79-1.35), P <  0.001]. The LAR was positively associated with disease severity, 28-day transplant-free survival [adjusted hazard ratio (HR) (95% confidence interval (CI)) for transplant or death: 2.18 (1.37-3.46), P =  0.001], and overall survival [adjusted HR (95% CI) for death: 2.14 (1.21-3.80), P =  0.009]. Compared with patients with LAR < 1.01, patients with LAR ≥ 1.01 had poor 28-day prognosis [all adjusted HR (95% CI) > 1, P  < 0.05]. Lactate was not a potential modifier of the relationship between LAR and short-term prognosis.

CONCLUSION

LAR was positively associated with disease severity and poor short-term prognosis in patients with COSSH ACLF.

Association between lactate-to-albumin ratio and all-cause mortality in critically ill cirrhotic patients with sepsis: a retrospective analysis of the MIMIC-IV database

BACKGROUND

The impact of lactate-to-albumin ratio (LAR) on mortality of critically ill cirrhotic patients with sepsis is scant.

METHODS

Critically ill cirrhotic patients with sepsis were obtained from the MIMIC-IV database (v3.0). Cox regression models alone and in combination with restricted cubic splines, generalized additive models and smoothed curve fitting were used to investigate the relationship between LAR and all-cause mortality.

RESULTS

A total of 1864 patients were included. The 30-day, 90-day, and 180-day all-cause mortality rates were 38.0%, 46.3%, and 49.5%, respectively. Higher LAR were significantly and nonlinearly associated with higher risks of 30-day, 90-day, and 180-day all-cause mortality (all adjusted HR = 1.17, P < 0.001). L-shaped associations between LAR and 30-day, 90-day, and 180-day all-cause mortality were observed, with an inflection point of 1.05 (P for log-likelihood ratio < 0.01). Compared with patients with LAR < 1.05, patients with LAR ≥ 1.05 had higher risks of 30-day, 90-day, and 180-day all-cause mortality (adjusted HR (95% CI): 1.48 (1.27-1.72), 1.44 (1.25-1.66), and 1.38 (1.21-1.57), respectively). No potential modifiers were found in the relationship between LAR and mortality.

CONCLUSIONS

LAR was positively and nonlinearly associated with all-cause mortality in critically ill cirrhotic patients with sepsis. Thus, it could be used as a prognostic biomarker.

Analysis of the prognostic efficacy of syndecan-1 for patients with ACLF and its functional role in liver regeneration

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by systemic inflammation with a high short-term mortality rate. Syndecan-1 (SDC-1) can independently predict the 90-day mortality of patients with septic shock. However, the role of SDC-1 in ACLF remains unknown.

METHODS

In this study, serum SDC-1 levels were examined in 2 cohorts, which included 174 ACLF patients. And a mouse ACLF model induced by tetrachloride, lipopolysaccharide, and D-galactosamine was established, to evaluate the effects of sulodexide and heparan sulfate (side chains of SDC-1) on ACLF in vivo.

RESULTS

Baseline serum SDC-1 levels in 101 ACLF patients (847.72, 499.79-1511.37 ng/ml) were significantly higher than in healthy controls (33.58, 27.08-43.34 ng/ml) (P < 0.0001). The baseline SDC-1 levels of patients who died or accepted a liver transplantation within 90 days were markedly higher than those of patients who survived (P < 0.05). A novel prognostic model (UIAS) based on upper gastrointestinal bleeding, INR, age, and SDC-1 was developed. The AUROC of the UIAS score for 28-day deterioration in ACLF patients was 0.884, indicating an obviously greater predictive performance for the outcomes of ACLF than those of the Child-Pugh (AUROC = 0.646), MELD (AUROC = 0.713), and COSSH-ACLF II scores (AUROC = 0.713). Moreover, we found that heparan sulfate and sulodexide could increase the expression of SDC-1 and attenuate liver injury, by promoting liver regeneration and inhibiting cell apoptosis through the activation of JAK1/STAT3 signalling.

CONCLUSIONS

Collectively, our findings suggest that SDC-1 represents a potential prognostic and therapeutic target for ACLF and should be further investigated.

Sulfonated albumin from hepatocytes accelerates liver fibrosis in nonalcoholic fatty liver disease through endoplasmic reticulum stress

BACKGROUND

Posttranslational modifications (PTM) of albumin occur in liver diseases; however, little is known about the source and function of sulfonated albumin, a significant modification of albumin occurring in nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the mechanism underlying sulfonated albumin production and its role in the progression of NAFLD-related liver fibrosis.

METHODS

Serum samples from healthy controls and patients with NAFLD were used to measure the proportion of sulfonated albumin. Mice models with NAFLD fed with high-fat diet (HFD) and methionine choline-deficient diet (MCD) were constructed. RNA sequencing, KEGG analysis, and GSEA were used to explore the mechanism of sulfonated albumin production and its mechanism of activating hepatic stellate cells (HSCs) and promoting the progression of liver fibrosis in NAFLD.

RESULTS

Sulfonated albumin levels increased significantly in both human and mouse NAFLD serum samples. In vivo studies in mice have shown that the intraperitoneal injection of sulfonated albumin promotes inflammation, hepatic steatosis, and liver fibrosis in NAFLD. In addition, autophagy has been verified as a key mechanism in the regulation of sulfonated albumin production. We also demonstrated that reactive oxygen species (ROS) production depends on the accumulation of damaged mitochondria and affects the production of sulfonated albumin under the regulation of autophagy. Hepatocyte-derived sulfonated albumin activates HSCs through the GAL3 receptor, thereby activating the endoplasmic reticulum (ER) stress pathway and promoting profibrotic activation of HSCs.

CONCLUSIONS

Our study demonstrated that sulfonated albumin activated HSCs through GAL3, thereby accelerating NAFLD-related liver fibrosis. Serum sulfonated albumin may be a potential diagnostic marker for liver fibrosis and an important target for the treatment of NAFLD-related liver fibrosis.

Nutritional risk assessment using the Nutritional Prognostic Index predicts mortality in Advanced Chronic Liver Disease patients

OBJECTIVES

Early clinical prognosis and mortality reduction remains a challenge in chronic liver disease (CLD). The full potential of the Nutritional Prognostic Index (NPI) for nutritional assessment and management in CLD patients remains unexplored. The aim of this study was to establish an NPI cutoff point for the identification of nutritional risk in advanced CLD (ACLD) patients, as well as to assess the NPI's ability to predict ACLD-associated mortality.

METHODS

This ethically approved prospective cohort study investigated malnutrition risk using both the NPI and the Royal Free Hospital-Nutritional Prioritizing Tool (RFH-NPT) in patients hospitalized for ACLD. NPI reference values were determined using a receiver operating characteristic curve. Associations between nutritional risk identified by the RFH-NPT and the NPI were assessed using Fisher's exact test, and agreement between tools was assessed using the Kappa index. The association between NPI-defined nutritional risk and 12-mo mortality was examined using Pearson Chi-square test.

RESULTS

The sample population consisted of 120 adults, comprising 84 (70%) male and 57 (50.9%) of alcoholic etiology and presenting as Child-Pugh A, B, or C at admission. The identified cutoff point for NPI was <41, identifying nutritional risk in 82.5% of patients. The NPI presented a statistically significant association with the RFH-NPT, with a substantial agreement coefficient of 0.34. An association between NPI <41 cutoff and mortality were observed, with 82.1% of the sample below cutoff experiencing mortality within 12 mo.

CONCLUSIONS

The NPI is a valuable nutritional marker for the identification of nutritional risk in ACLD and is a simple and effective assessment tool that can aid in early CLD prognosis assessment. Validation, however, remains necessary in other CLD populations of different etiologies.

Therapeutic Plasma Exchange in Hepatology: Indications, Techniques, and Practical Application

It is sobering that many liver failure patients die in the absence of liver transplantation (LT), and reducing its morbidity and mortality urgently needs more non-transplant treatment options. Among the several artificial liver support devices available, therapeutic plasma exchange (TPE) is the only one that improves survival in acute liver failure (ALF) patients. In many other disorders, data on survival benefits and successful bridging to transplant is encouraging. TPE removes the entire plasma, including damage-associated-molecular patterns, and replaces it with healthy donor fresh frozen plasma. In contrast, other artificial liver support systems (ALSS) correct the blood composition through dialysis techniques. TPE has become increasingly popular due to advances in apheresis techniques and a better understanding of its applicability in treating liver failure's pathophysiology. It provides metabolicdetoxification, and synthetic functions and modulates early innate immunity, fulfilling the role of ALSS. TPE is readily available in intensive care units, dialysis units, or blood banks and has enormous potential to improve survival outcomes. Hepatologists must take advantage of this treatment option by thoroughly understanding its most frequent indications and its rationale and techniques. This primer on TPE for liver clinicians covers its current clinical, technical, and practical applications, addresses the knowledge gaps, and provides future directions.

Introduction to the concept of effective albumin concentration

PURPOSE

The purpose of this article is to discuss how the structural and presumably functional integrity of albumin, as described by the concept of effective albumin concentration (eAlb), has potentially important clinical implications beyond the total albumin concentration (tAlb) routinely reported by clinical laboratories.

SUMMARY

Albumin has several functions beyond its oncotic effects, including molecule binding, substance transport, detoxification actions, and serving as an antioxidant. However, there are conformational changes that occur during or following the manufacture of albumin and during its administration to patients with various disease states, such as decompensated liver disease, that often impair these functions. Such impairments are not reflected in tAlb values reported by clinical laboratories and might explain the disconnect often seen between albumin's proposed beneficial mechanistic functions and its less-than-predicted clinical effectiveness as noted in published studies. The concept of eAlb has been introduced to describe albumin with structural and functional integrity. Limited studies have found associations between eAlb values and patient prognostic indicators, but the techniques used to decide these effective concentrations to date are complicated and require specialized equipment and experienced researchers for proper interpretation.

CONCLUSION

Estimation of eAlb may provide valuable information on the functional ability of albumin beyond the tAlb reported by clinical laboratories, but more research is needed to decide how this information is best used in the clinical setting.

Comparative analysis of purity of human albumin preparations for clinical use

BACKGROUND

Albumin is the most prevalent plasma protein and serves numerous physiological roles, both in body fluid management and in various other capacities. In many diseases, a deficiency of albumin has been observed, and in certain conditions, albumin substitution has been demonstrated to improve outcome in comparison to plasma expansion using crystalloid or other colloid solutions. The favourable effects of using albumin in patients with liver cirrhosis are likely associated with the non-oncotic functions of albumin. Albumin for clinical use is obtained through fractionation of pooled donor plasma. The production procedures are optimized to ensure pure, chemically uncompromised and native protein.

RESULTS

We have extensively analysed commercial preparations of human albumin for clinical use from six different providers. Parameters that must correspond to the requirements of international pharmacopoeias were assessed (aluminium, ethanol, sodium, the presence of dimers and oligomers) and found to conform in all cases. In addition, we used for the first time nuclear magnetic resonance (NMR) as an additional analytical approach for investigating in greater depth the quality of a biological remedy gained from human plasma. We applied both 1H NMR and 13C-HSQC for confirming the identity of the albumin preparations, which also conformed in all cases. Moreover, we utilized T2-filtered 1H NMR and 13C-HSQC measurements to identify the presence of small molecules in the preparations. This demonstrated similar patterns of additional substances present, but also unveiled certain differences in purity in the products of the different providers.

SIGNIFICANCE

Our analyses confirmed that albumin preparations in clinical use conform to the requirements. We furthermore demonstrate that NMR measurements can provide further depth in identity and purity measurements of biologicals. Despite largely standardized protocols in pharmaceutical albumin production, our in-depth analyses revealed differences in purity. Some samples exhibited lower levels of components other than albumin. We discuss possible causes of these observations and their potential implications for clinical therapy.

Proteomic analysis of mouse liver lesions at all three stages of Echinococcus granulosus infection

Echinococcus granulosus, a zoonotic parasite, can severely damage host health or even lead to host death. In humans, early diagnosis of E. granulosus infection is difficult because the initial stages of the infection tend to be asymptomatic, this delays treatment and worsens prognosis in most patients. Herein, we present a comprehensive, temporal proteomic atlas of the liver at three stages of E. granulosus infection and analyze the changes in the proteome of host focal lesions; this atlas may provide an overview of the effects of E. granulosus in the host, as well as the interactions between them. We identified 3,197 proteins from mice model at 1, 3, and 6 months after E. granulosus infection; of these proteins, 760 were differentially expressed (520 upregulated; 240 downregulated). Moreover, 228 differentially expressed proteins were screened through cluster analysis and classified into four clusters according to their changing trends. Subsequently, candidate molecules related to cyst invasion, growth, candidate pathways and proteins related to angiogenesis were noted to demonstrate important value in mouse liver. Next, we used western blotting to verify the presence of the aforementioned proteins in mouse liver. In the later stages, E. granulosus infection was noted to result in significant enrichment of crucial proteins facilitating protoscoleces growth and development and inhibition of amino acid and lipid metabolic enzyme expression in mouse liver; it was also noted to transform host metabolism by weakening oxidative phosphorylation and enhancing glycolysis. In conclusion, we explored the molecular mechanisms underlying the parasitic processes of E. granulosus through proteomic analysis. Our results provide evidence that may enable the exploration of core regulatory targets for early and effective diagnosis and immunotherapy of E. granulosus infection, as well as parasite-host interactions involved in cystic echinococcosis development.

Artificial intelligence-based evaluation of prognosis in cirrhosis

Cirrhosis represents a significant global health challenge, characterized by high morbidity and mortality rates that severely impact human health. Timely and precise prognostic assessments of liver cirrhosis are crucial for improving patient outcomes and reducing mortality rates as they enable physicians to identify high-risk patients and implement early interventions. This paper features a thorough literature review on the prognostic assessment of liver cirrhosis, aiming to summarize and delineate the present status and constraints associated with the application of traditional prognostic tools in clinical settings. Among these tools, the Child-Pugh and Model for End-Stage Liver Disease (MELD) scoring systems are predominantly utilized. However, their accuracy varies significantly. These systems are generally suitable for broad assessments but lack condition-specific applicability and fail to capture the risks associated with dynamic changes in patient conditions. Future research in this field is poised for deep exploration into the integration of artificial intelligence (AI) with routine clinical and multi-omics data in patients with cirrhosis. The goal is to transition from static, unimodal assessment models to dynamic, multimodal frameworks. Such advancements will not only improve the precision of prognostic tools but also facilitate personalized medicine approaches, potentially revolutionizing clinical outcomes.

Impact of albumin infusion on prognosis in ICU patients with cirrhosis and AKI: insights from the MIMIC-IV database

Background

Acute kidney injury (AKI) is common in cirrhotic patients, especially in the intensive care unit (ICU), and is often associated with poor prognosis. Albumin is often used for plasma volume expansion, but its efficacy in cirrhotic patients with AKI [excluding hepatorenal syndrome (HRS)] is debated. This study aimed to assess the impact of albumin therapy on prognosis in ICU patients with cirrhosis and non-HRS AKI.

Methods

A retrospective analysis was conducted using the MIMIC-IV 2.2 database. The primary endpoint was 28-day mortality. Inverse probability of treatment weighting (IPTW) was used to balance baseline characteristics between the albumin and non-albumin groups.

Results

A total of 1,623 patients were included, with 586 receiving albumin. After IPTW, the sample sizes were 1,713 in the non-albumin group and 1,490 in the albumin group. Albumin administration was associated with higher rates of AKI recovery at 48 h but did not improve 28-day mortality in the overall cohort. Further analysis revealed that using 5% albumin concentration was associated with improved 28-day mortality (HR 0.68; 95% CI 0.49-0.95; p = 0.025), whereas 25% albumin did not show benefit. In patients with high bilirubin levels, albumin treatment significantly reduced 28-day mortality. However, albumin therapy may increase 28-day mortality in certain subgroups, including patients with chronic kidney disease and baseline albumin levels >3.3 g/dL.

Conclusion

Although albumin therapy improved 28-day mortality in some cases, it may also increase mortality in certain subgroups. The use of albumin in critically ill patients with cirrhosis and AKI should be approached with greater consideration of its risks and benefits.

Long-term albumin improves the outcomes of patients with decompensated cirrhosis and diabetes mellitus: Post hoc analysis of the ANSWER trial

Type-2 diabetes mellitus is a frequent comorbidity of cirrhosis independently associated with cirrhosis-related complications and mortality. This post hoc analysis of the ANSWER trial database assessed the effects of long-term human albumin (HA) administration on top of the standard medical treatment (SMT) on the clinical outcomes of a subgroup of 85 outpatients with liver cirrhosis, uncomplicated ascites and insulin-treated diabetes mellitus type 2 (ITDM). Compared to patients in the SMT arm, the SMT + HA group showed a better overall survival (86% vs. 57%, p = .016) and lower incidence rates of paracenteses, overt hepatic encephalopathy, bacterial infections, renal dysfunction and electrolyte disorders. Hospital admissions did not differ between the two arms, but the number of days spent in hospital was lower in the SMT + HA group. In conclusion, in a subgroup of ITDM outpatients with decompensated cirrhosis and ascites, long-term HA administration was associated with better survival and a lower incidence of cirrhosis-related complications.

Efficacy of albumin use in decompensated cirrhosis and real-world adoption in Australia

The current treatment approach to patients with liver cirrhosis relies on the individual management of complications. Consequently, there is an unmet need for an overall therapeutic strategy for primary and secondary prevention of complications. The clinical potential of long-term albumin infusions supported by recent clinical trials has expanded its indications and holds promise to transform the management and secondary prevention of cirrhosis-related complications. This renewed interest in albumin comes with inherent controversies, compounding challenges and pressing need for rigorous evaluation of its clinical potential to capitalize on its therapeutic breakthroughs. Australia is among a few countries worldwide to adopt outpatient human albumin infusion. Here, we summarize currently available evidence of the potential benefits of human albumin for the management of multiple liver cirrhosis-related complications and discuss key challenges for wide application of long-term albumin administration strategy in Australian clinical practice. Australian Gastroenterological week (AGW), organised by the Gastroenterological Society of Australia (GESA), was held between 9-11 September 2022. A panel of hepatologists, advanced liver nurses and one haematologist, were invited to a roundtable meeting to discuss the use of long-term albumin infusions for liver cirrhosis. management in Australia. In this review, we summarise the proceedings of this meeting in context of the current literature.

Hypoalbuminemia contributes to ascites formation via sodium and water retention: Evidence from clinical date and albumin deficient mice

Albumin infusions improve circulatory and renal function in patients with decompensated cirrhosis. However, there is no convincing evidence that hypoalbuminemia contributes to ascites formation in liver cirrhosis. The aim of our study is to determine the exact role of hypoalbuminemia in the formation of ascites caused by liver cirrhosis and its underlying mechanism. Clinical profiles of patients with liver cirrhosis retrospectively analyzed. The details of albumin involved in ascites formation were investigated in rat model and murine model. Statistical analysis demonstrated hypoalbuminemia was an independent risk factor for ascites formation in patients with liver cirrhosis (OR = 0.722, P < 0.001). In carbon tetrachloride (CCl4)-induced rat model of liver cirrhosis, a significant reduction in serum albumin was observed in rats with ascites (13.37 g/L) compared with rats without ascites (21.43 g/L, P < 0.001). In thioacetamide (TAA)-treated mice, ascites amount of heterozygous albumin (Alb+/-) mice (112.0 mg) was larger than that of wild-type (Alb+/+) mice (58.46 mg, P < 0.001). In CCl4-induced chronic liver injury, ascites amounts of Alb+/- or Alb+/+ mice were 80.00 mg or 48.46 mg (P = 0.001). Further study demonstrated 24-h urinary sodium excretion in Alb+/- mice was lower than that of Alb+/+ mice in TAA/CCl4-induce murine models of liver cirrhosis. Additionally, serum sodium concentration of Alb+/- mice was lower than that of Alb+/+ mice. In cirrhotic mice, higher level of antidiuretic hormone was observed in Alb+/- mice compared with the control; and renal aquaporin (AQP2) expression in Alb+/- mice was significantly higher than that of WT mice. These revealed hypoalbuminemia contributed to the occurrence of ascites in liver cirrhosis through sodium and water retention.

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.

Role of albumin infusion in cirrhosis-associated complications

Cirrhosis is an advanced-stage liver disease that occurs due to persistent physiological insults such as excessive alcohol consumption, infections, or toxicity. It is characterised by scar tissue formation, portal hypertension, and ascites (accumulation of fluid in the abdominal cavity) in decompensated cirrhosis. This review evaluates how albumin infusion ameliorates cirrhosis-associated complications. Since albumin is an oncotic plasma protein, albumin infusion allows movement of water into the intravascular space, aids with fluid resuscitation, and thereby contributes to resolving cirrhosis-induced hypovolemia (loss of extracellular fluid) seen in ascites. Thus, albumin infusion helps prevent paracentesis-induced circulatory dysfunction, a complication that occurs when treating ascites. When cirrhosis advances, other complications such as spontaneous bacterial peritonitis and hepatorenal syndrome can manifest. Infused albumin helps mitigate these by exhibiting plasma expansion, antioxidant, and anti-inflammatory functions. In hepatic encephalopathy, albumin infusion is thought to improve cognitive function by reducing ammonia concentration in blood and thereby tackle cirrhosis-induced hepatocyte malfunction in ammonia clearance. Infused albumin can also exhibit protective effects by binding to the cirrhosis-induced proinflammatory cytokines TNFα and IL6. While albumin administration has shown to prolong overall survival of cirrhotic patients with ascites in the ANSWER trial, the ATTIRE and MACHT trials have shown either no effect or limitations such as development of pulmonary oedema and multiorgan failure.  Thus, albumin infusion is not a generic treatment option for all cirrhosis patients. Interestingly, cirrhosis-induced structural alterations in native albumin (which lead to formation of different albumin isoforms) can be used as prognostic biomarkers because specific albumin isoforms indicate certain complications of decompensated cirrhosis.

Effect of albumin infusion on oxidative albumin modification and albumin binding capacity in chronic liver failure

Oxidative albumin modification and impaired albumin binding function have been described both in chronic liver failure and for therapeutic albumin solutions. The aim of the present study was to evaluate the effect of albumin infusion on redox state and binding function of circulating albumin. We studied 20 patients with cirrhosis who routinely received albumin infusions for prevention of post-paracentesis circulatory dysfunction or treatment of hepatorenal syndrome. We measured albumin fractions by redox state of cysteine-34 and albumin binding properties using dansylsarcosine as site II ligand. Therapeutic albumin solutions showed high contents of human nonmercaptalbumin-1 and human nonmercaptalbumin-2, exceeding the respective values in our patients with decompensated cirrhosis. An initial protocol for the first nine patients sampled at baseline, 24 h and 48 h after albumin infusion revealed no significant changes of oxidized albumin species or albumin binding properties. However, a modified protocol for the remaining 11 patients sampled at baseline, <1 h after and 24 h after albumin infusion revealed short-lived changes of oxidized albumin species while no changes in albumin binding properties were observed. In conclusion, therapeutic albumin infusion transiently changed albumin redox state but did not improve binding function of circulating albumin in chronic liver failure.

Albumin, an interesting and functionally diverse protein, varies from 'native' to 'effective' (Review)

Human serum albumins (HSAs) are synthesized in the liver and are the most abundant proteins in plasma of healthy human. They play an important role in the pathophysiological processes of the liver and even the whole organism. Previous studies have mainly focused on the regulation of HSAs' expression. However, with the progress of research in recent years, it has been found that the content of circulating albumin cannot fully reflect the biological function of albumin itself. Given the aforementioned fact, the concept of serum 'effective albumin concentration' has been proposed. It refers to the content of albumin that is structurally and functionally intact. Alterations in the molecular structure and function of albumin have been reported in a variety of diseases, including liver disease. Moreover, these changes have been verified to affect the progression of oxidative stress‑related diseases. However, the link between albumin structure and function has not been fully elaborated, and the mechanisms by which different forms of albumin affect disease also need to be further investigated. In this context, the present review mainly expounded the biological characteristics and functions of albumin, summarized the different types of post‑translational modification of albumin, and discussed their functional changes and possible mechanisms in non‑alcoholic fatty liver disease, alcoholic hepatitis, viral hepatitis and different stages of cirrhosis. This will help to improve understanding of the role of albumin in disease development and provide a more comprehensive physiological basis for it in disease treatment.

Binding and detoxification efficiency of albumin decline after haemodialysis

BACKGROUND

Albumin, as the most abundant plasma protein, represents a target structure for both drug and physicochemical therapeutic approaches to eliminate uraemic toxins more efficiently. Potentially, this approach could reduce mortality of haemodialysis patients. However, little is known about albumin functional properties in these patients and its alteration by haemodialysis treatment.

METHODS

The binding and detoxification efficiency of albumin were assessed by electron paramagnetic resonance spectroscopy using a spin-labelled fatty acid. Binding efficiency (BE) reflects strength and amount of bound fatty acids under certain ethanol concentration. Detoxification efficiency (DTE) reflects the molecular flexibility of the patient's albumin molecule, thus the ability to change the conformation depending on ethanol concentration. Percentage of BE and DTE are depicted in relation to healthy individuals (100%).

RESULTS

Fifty-eight patients (59% male, median age 68 years, median time on haemodialysis 32 months) were included in the study. Before haemodialysis treatment, albumin binding and detoxification efficiency were substantially below healthy individuals [median BE 52% (interquartile range, IQR, 45%-59%); median DTE 38% (IQR 32-49%)]. After haemodialysis treatment, median BE and DTE significantly decreased [BE 28% (IQR 20-41%); DTE 11% (IQR 7%-27%; P < .001)]. BE and DTE decline after haemodialysis was not dependent on age, sex or treatment modalities, but was to a certain extent on the level of non-esterified fatty acids.

CONCLUSION

Albumin binding and detoxification efficiency of fatty acids in maintenance haemodialysis patients were substantially below those in healthy individuals and even declined after dialysis treatment. These findings might be helpful when considering new therapeutic approaches in maintenance haemodialysis patients.

Absolute Quantification of Human Serum Albumin Isoforms by Internal Calibration Based on a Top-Down LC-MS Approach

Well-characterized biomarkers using reliable quantitative methods are essential for the management of various pathologies such as diabetes, kidney, and liver diseases. Human serum albumin (HSA) isoforms are gaining interest as biomarkers of advanced liver pathologies. In view of the structural alterations observed for HSA, insights into its isoforms are required to establish them as reliable biomarkers. Therefore, a robust absolute quantification method seems necessary. In this study, we developed and validated a far more advanced top-down liquid chromatography-mass spectrometry (LC-MS) method for the absolute quantification of HSA isoforms, using myoglobin (Mb) as an internal standard for quantification and for mass recalibration. Two different quantification approaches were investigated based on peak integration from the deconvoluted spectrum and extracted ion chromatogram (XIC). The protein mixture human serum albumin/myoglobin eluted in well-shaped separated peaks. Mb allowed a systematic mass recalibration for every sample, resulting in extremely low mass deviations compared to conventional deconvolution-based methods. In total, eight HSA isoforms of interest were quantified. Specific-isoform calibration curves showing good linearity were obtained by using the deconvoluted peaks. Noticeably, the HSA ionization behavior appeared to be isoform-dependent, suggesting that the use of an enriched isoform solution as a calibration standard for absolute quantification studies of HSA isoforms is necessary. Good repeatability, reproducibility, and accuracy were observed, with better sensitivity for samples with low albumin concentrations compared to routine biochemical assays. With a relatively simple workflow, the application of this method for absolute quantification shows great potential, especially for HSA isoform studies in a clinical context, where a high-throughput method and sensitivity are needed.

Early detection of liver injuries by the Serum enhanced binding test sensitive to albumin post-transcriptional modifications

Early and sensitive biomarkers of liver dysfunction and drug-induced liver injury (DILI) are still needed, both for patient care and drug development. We developed the Serum Enhanced Binding (SEB) test to reveal post-transcriptional modifications (PTMs) of human serum albumin resulting from hepatocyte dysfunctions and further evaluated its performance in an animal model. The SEB test consists in spiking serum ex-vivo with ligands having specific binding sites related to the most relevant albumin PTMs and measuring their unbound fraction. To explore the hypothesis that albumin PTMs occur early during liver injury and can also be detected by the SEB test, we induced hepatotoxicity in male albino Wistar rats by administering high daily doses of ethanol and CCl4 over several days. Blood was collected for characterization and quantification of albumin isoforms by high-resolution mass spectrometry, for classical biochemical analyses as well as to apply the SEB test. In the exposed rats, the appearance of albumin isoforms paralleled the positivity of the SEB test ligands and histological injuries. These were observed as early as D3 in the Ethanol and CCl4 groups, whereas the classical liver tests (ALT, AST, PAL) significantly increased only at D7. The behavior of several ligands was supported by structural and molecular simulation analysis. The SEB test and albumin isoforms revealed hepatocyte damage early, before the current biochemical biomarkers. The SEB test should be easier to implement in the clinics than albumin isoform profiling.

Predictors of clinical trajectories of patients with acutely decompensated cirrhosis. An external validation of the PREDICT study

BACKGROUND AND AIMS

The PREDICT study recently showed that acutely decompensated (AD) patients with cirrhosis can present three different clinical phenotypes in the 90 days after admission: (1) pre-ACLF, developing acute-on-chronic liver failure (ACLF); (2) unstable decompensated cirrhosis (UDC), being re-admitted for AD without ACLF and (3) stable decompensated cirrhosis (SDC), not presenting readmission or ACLF. This study aimed to externally validate the existence of these three distinct trajectories and to identify predictors for the occurrence of each trajectory.

METHODS

Baseline data, 3-month ACLF and readmission incidence and 1-year survival were analysed in a prospective cohort of patients admitted for AD. A multinomial multivariable model was used to evaluate the association between baseline features and clinical trajectories.

RESULTS

Of the 311 patients enrolled, 55% met the criteria for SDC, 18% for UDC and 27% for pre-ACLF, presenting a significantly different 1-year mortality: pre-ACLF 65%, UDC 46%, SDC 21% (p < .001). The presence of hepatic encephalopathy (HE) was associated with UDC (p = .043), while the absence of ascites to SDC (p = .017). Among laboratory parameters, an increase in MELD-Na (p = .001) and C-reactive protein (p = .009) and a decrease in haemoglobin (p = .004) and albumin (p = .008) levels were associated with pre-ACLF.

CONCLUSION

The present study confirms that AD patients have three different clinical trajectories with different mortality rates. Besides the severity of cirrhosis, the association with C-reactive protein supports the predominant role of systemic inflammation in ACLF pathophysiology. Finally, HE is associated with the UDC phenotype highlighting the need for better management of this complication after discharge.

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.

Albumin administration in internal medicine: A journey between effectiveness and futility

Albumin is the most abundant circulating protein and provides about 70% of the plasma oncotic power. The molecule also carries many other biological functions (binding, transport and detoxification of endogenous and exogenous compounds, antioxidation, and modulation of inflammatory and immune responses). Hypoalbuminemia is a frequent finding in many diseases, representing usually only a biomarker of poor prognosis rather than a primary pathophysiological event. Despite that, albumin is prescribed in many conditions based on the assumption that correction of hypoalbuminemia would lead to clinical benefits for the patients. Unfortunately, many of these indications are not supported by scientific evidence (or have been even disproved), so that a large part of albumin use is nowadays still inappropriate. Decompensated cirrhosis is the clinical area where albumin administration has been extensively studied and solid recommendations can be made. Besides prevention and treatment of acute complications, long-term albumin administration in patients with ascites has emerged in the last decade has a potential new disease-modifying treatment. In non-hepatological settings, albumin is widely used for fluid resuscitation in sepsis and critical illnesses, with no clear superiority over crystalloids. In many other conditions, scientific evidence supporting albumin prescription is weak or even absent. Thus, given its high cost and limited availability, action is needed to avoid the use of albumin for inappropriate and futile indications to ensure its availability in those conditions for which albumin has been demonstrated to have a real effectiveness and an advantage for the patient.

Review article: Emerging and current management of acute-on-chronic liver failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a clinically and pathophysiologically distinct condition from acutely decompensated cirrhosis and is characterised by systemic inflammation, extrahepatic organ failure, and high short-term mortality.

AIMS

To provide a narrative review of the diagnostic criteria, prognosis, epidemiology, and general management principles of ACLF. Four specific interventions that are explored in detail are intravenous albumin, extracorporeal liver assist devices, granulocyte-colony stimulating factor, and liver transplantation.

METHODS

We searched PubMed and Cochrane databases for articles published up to July 2023.

RESULTS

Approximately 35% of hospital inpatients with decompensated cirrhosis have ACLF. There is significant heterogeneity in the criteria used to diagnose ACLF; different definitions identify different phenotypes with varying mortality. Criteria established by the European Association for the Study of the Liver were developed in prospective patient cohorts and are, to-date, the most well validated internationally. Systemic haemodynamic instability, renal dysfunction, coagulopathy, neurological dysfunction, and respiratory failure are key considerations when managing ACLF in the intensive care unit. Apart from liver transplantation, there are no accepted evidence-based treatments for ACLF, but several different approaches are under investigation.

CONCLUSION

The recognition of ACLF as a distinct entity from acutely decompensated cirrhosis has allowed for better patient stratification in clinical settings, facilitating earlier engagement with the intensive care unit and liver transplantation teams. Research priorities over the next decade should focus on exploring novel treatment strategies with a particular focus on which, when, and how patients with ACLF should be treated.

Semi-synthetic human albumin isoforms: Production, structure, binding capacities and influence on a routine laboratory test

Human Serum Albumin (HSA) undergoes Post-Translational-Modifications (PTMs) leading to isoforms affecting its oncotic and non-oncotic properties. HSA is comprised of several isoforms whose abundance may vary with pathologies such as diabetes, kidney and liver diseases. Studying their impact separately may help to understand their sources and potential pathogenicity and further their evaluation as biomarkers. The present study examined semi-synthetic HSA isoforms to investigate independently their structure by means of advanced mass spectrometry techniques (LC-TOF-MS and ICP-MS), influence on the HSA binding/antioxidant activities using a binding capacity test, and potential impact on albumin quantification by a routine immunoturbidimetric assay. Applying different chemical reactions to a commercial HSA solution, we obtained different solutions enriched up to 53 % of native HSA, 78 % of acetylated HSA, 71 % of cysteinylated HSA, 94 % of oxidized HSA, 58 % of nitrosylated HSA and 96 % of glycated HSA, respectively. Moreover, the semi-synthetic isoforms showed differently altered binding capacities for a panel of ligands (Cu, Cd, Au, Ds and L-T4). Furthermore, immunoturbidimetry was found to be insensitive to the presence and abundance of the different isoforms. The fully characterized semi synthetic HSA isoforms obtained should be useful to further investigate their pathogenicity and potential roles as biomarkers.

Exploring Albumin Functionality Assays: A Pilot Study on Sepsis Evaluation in Intensive Care Medicine

Human serum albumin (HSA) as the most abundant plasma protein carries multifunctional properties. A major determinant of the efficacy of albumin relies on its potent binding capacity for toxins and pharmaceutical agents. Albumin binding is impaired in pathological conditions, affecting its function as a molecular scavenger. Limited knowledge is available on the functional properties of albumin in critically ill patients with sepsis or septic shock. A prospective, non-interventional clinical trial assessed blood samples from 26 intensive care patients. Albumin-binding capacity (ABiC) was determined by quantifying the unbound fraction of the fluorescent marker, dansyl sarcosine. Electron paramagnetic resonance fatty acid spin-probe evaluated albumin's binding and detoxification efficiencies. Binding efficiency (BE) reflects the strength and amount of bound fatty acids, and detoxification efficiency (DTE) indicates the molecular flexibility of patient albumin. ABiC, BE, and DTE effectively differentiated control patients from those with sepsis or septic shock (AUROC > 0.8). The diagnostic performance of BE showed similarities to procalcitonin. Albumin functionality correlates with parameters for inflammation, hepatic, or renal insufficiency. Albumin-binding function was significantly reduced in critically ill patients with sepsis or septic shock. These findings may help develop patient-specific algorithms for new diagnostic and therapeutic approaches.

Use of albumin infusion for cirrhosis-related complications: An international position statement

BACKGROUND & AIMS

Numerous studies have evaluated the role of human albumin (HA) in managing various liver cirrhosis-related complications. However, their conclusions remain partially controversial, probably because HA was evaluated in different settings, including indications, patient characteristics, and dosage and duration of therapy.

METHODS

Thirty-three investigators from 19 countries with expertise in the management of liver cirrhosis-related complications were invited to organise an International Special Interest Group. A three-round Delphi consensus process was conducted to complete the international position statement on the use of HA for treatment of liver cirrhosis-related complications.

RESULTS

Twelve clinically significant position statements were proposed. Short-term infusion of HA should be recommended for the management of hepatorenal syndrome, large volume paracentesis, and spontaneous bacterial peritonitis in liver cirrhosis. Its effects on the prevention or treatment of other liver cirrhosis-related complications should be further elucidated. Long-term HA administration can be considered in specific settings. Pulmonary oedema should be closely monitored as a potential adverse effect in cirrhotic patients receiving HA infusion.

CONCLUSIONS

Based on the currently available evidence, the international position statement suggests the potential benefits of HA for the management of multiple liver cirrhosis-related complications and summarises its safety profile. However, its optimal timing and infusion strategy remain to be further elucidated.

IMPACT AND IMPLICATIONS

Thirty-three investigators from 19 countries proposed 12 position statements on the use of human albumin (HA) infusion in liver cirrhosis-related complications. Based on current evidence, short-term HA infusion should be recommended for the management of HRS, LVP, and SBP; whereas, long-term HA administration can be considered in the setting where budget and logistical issues can be resolved. However, pulmonary oedema should be closely monitored in cirrhotic patients who receive HA infusion.

Determination of binding characteristics as a measure for effective albumin using different methods

BACKGROUND & AIMS

Transport functions of albumin are of clinical and pharmacological interest and are determined by albumin's properties like posttranslational modifications or bound ligands. Both are affected in pathological conditions and in therapeutic grade albumin solutions. The term effective albumin concentration was introduced as a measure of functionally intact albumin. Our aim was to evaluate the impact of ligands and modifications with different approaches as a measure of effective albumin.

APPROACH & RESULTS

We used a spin labelled fatty acid and dansylsarcosine to characterize binding properties of albumin i) prepared from plasma of patients and healthy control donors, ii) measured directly out of plasma, iii) research grade albumin, iv) in vitro modified albumin, and v) therapeutic infusion solutions before and after removal of stabilizers. Bilirubin is the main determinant for binding function in patients' albumin. In in vitro prepared albumin bound fatty acids correlated with impaired binding. Human nonmercaptalbumin1, not human nonmercaptalbumin2, showed reduced binding properties. Binding and transport function of therapeutic albumin was severely impaired and restored by filtration. Glycation of research grade albumin had no effect on the binding of dansylsarcosine and only a minor effect on fatty acid binding.

CONCLUSIONS

Our results suggest that effective albumin -in terms of binding properties- is primarily determined by bound ligands and only to a minor extent by posttranslational modifications. Characterizing albumin directly from plasma better reflects the physiological situation whereas in the case of therapeutic grade albumin stabilizers should be removed to make its binding properties accessible.

Posttranslational-modifications of human-serum-albumin analysis by a top-down approach validated by a comprehensive bottom-up analysis

The posttranslational modifications (PTM) of human serum albumin (HSA) can result in the development of isoforms that have been identified as potential biomarkers for advanced hepatic diseases. However, previous approaches using top-down (TD) analysis to identify isoforms based on molecular weight may have resulted in misidentifications. The nature of the identified isoforms has never been confirmed in previous works. Here, we aimed to critically evaluate TD for the characterization and determination of HSA isoforms in patients and make an inventory of HSA-PTM. Serum samples from control subjects and patients with liver dysfunctions were analyzed using both top-down (TD) and bottom-up (BU) approaches. TD analysis involved using a LC-TOF-MS system to obtain a multicharged spectrum of HSA, which was deconvoluted to identify isoforms. Spectra were then used for relative quantitation analysis of albumin isoform abundances based on trapezoidal integration. For BU analysis, serums were reduced +/- alkylated, digested with trypsin and analyzed in the Q-TOF, data-dependent acquisition (DDA) mode to generate a SWATH-MS high-resolution mass spectral library of all HSA peptides. Tryptic digests of another set of serum samples were then analyzed using data-independent acquisition (DIA) mode to confirm the presence of HSA isoforms and their modification sites. TD detected 15 isoforms corresponding to various modifications, including glycation, cysteinylation, nitrosylation, and oxidation (di- and tri-). In BU, the spectral library containing 127 peptides allowed for the characterization of the important isoforms with their modified sites, including some modifications that were only characterized in BU (carbamylation, deamidation, and amino-acid substitution). The method used for determining isoforms offered acceptable reproducibility (intra-/inter-assay CVs < 15%) for all isoforms present at relative abundances higher than 2%. Overall, the study found that several isoforms could be missed or misidentified by TD. However, all HSA isoforms identified by TD and reported to be relevant in liver dysfunctions were confirmed by BU. This critical evaluation of TD approach helped design an adequate and reliable method for the characterization of HSA isoforms in patients and offers the possibility to estimate isoform abundances within 3 min. These findings have significant implications for the diagnosis and treatment of liver dysfunctions.

Application of effective albumin concentration in treatment of chronic liver disease

Albumin is a non-glycosylated plasma protein. Besides the role of increasing blood volume and maintaining plasma colloid osmotic pressure, albumin also has multiple biological functions such as transport, antioxidant and anti-inflammatory effects, immune regulation, etc. In-depth studies on the structure and function of albumin have revealed that the post-transcriptional modification of albumin reduces the effective albumin concentration in patients with chronic liver disease, so the clinically effective albumin concentration rather than total albumin concentration can more accurately reflect the disease progression and prognosis, and more effectively guide exogenous albumin treatment in such patients. This article summarizes the clinical correlation between post-transcriptional modification of albumin and the liver and its related diseases, as well as the studies on effective albumin, in order to provide evidence-based information on effective albumin concentration and to better guide the clinical treatment of chronic liver disease.

Escherichia coli-derived outer-membrane vesicles induce immune activation and progression of cirrhosis in mice and humans

BACKGROUND AND AIMS

Decompensated cirrhosis with fibrosis progression causes portal hypertension followed by an oedematous intestinal tract. These conditions weaken the barrier function against bacteria in the intestinal tract, a condition called leaky gut, resulting in invasion by bacteria and bacterial components. Here, we investigated the role of outer-membrane vesicles (OMVs) of Escherichia coli, which is the representative pathogenic gut-derived bacteria in patients with cirrhosis in the pathogenesis of cirrhosis.

METHODS

We investigated the involvement of OMVs in humans using human serum and ascites samples and also investigated the involvement of OMVs from E. coli in mice using mouse liver-derived cells and a mouse cirrhosis model.

RESULTS

In vitro, OMVs induced inflammatory responses to macrophages and neutrophils, including the upregulation of C-type lectin domain family 4 member E (Clec4e), and induced the suppression of albumin production in hepatocytes but had a relatively little direct effect on hepatic stellate cells. In a mouse cirrhosis model, administration of OMVs led to increased liver inflammation, especially affecting the activation of macrophages, worsening fibrosis and decreasing albumin production. Albumin administration weakened these inflammatory changes. In addition, multiple antibodies against bacterial components were increased with a progressing Child-Pugh grade, and OMVs were detected in ascites of patients with decompensated cirrhosis.

CONCLUSIONS

In conclusion, OMVs induce inflammation, fibrosis and suppression of albumin production, affecting the pathogenesis of cirrhosis. We believe that our study paves the way for the future prevention and treatment of cirrhosis.

Research progress on short-term prognosis of acute-on-chronic liver failure

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a clinical syndrome characterized as a severe condition with rapid progression, poor therapeutic response and poor prognosis. Early and timely evaluation of the prognosis is helpful for providing appropriate clinical intervention and prolonging patient survival.

AREAS COVERED

Currently, there are no specific dynamic and comprehensive approaches to assess the prognosis of patients with ACLF. This article reviews the progress in evaluating the short-term prognosis of ACLF to provide future directions for more dynamic prospective large-scale multicenter studies and a basis for individualized and precise treatment for ACLF patients. We searched PubMed and Web of Science with the term 'acute on chronic liver failure' and 'prognosis.' There was no date or language restriction, and our final search was on 26 October 2022.

EXPERT OPINION

ACLF is a dynamic process, and the best prognostic marker is the clinical evolution of organ failure over time. New prognostic markers are developing not only in the fields of genetics and histology but also toward diversification combined with imaging. Determining which patients will benefit from continued advanced life support is a formidable challenge, and accurate short-term prognostic assessments of ACLF are a good approach to addressing this issue.

Effects of Rifaximin on Circulating Albumin Structures and Serum Ammonia Levels in Patients with Liver Cirrhosis: A Preliminary Study

Circulating albumin structures, including their oxidized and reduced forms, are involved in hepatic encephalopathy (HE) development. However, the effects of rifaximin, a key drug in HE treatment, on the circulating albumin structure in patients with liver cirrhosis remain unclear. In this multicenter prospective study, eight patients with hyperammonemia (≥80 μg/dL) were enrolled. The circulating albumin structure was evaluated using the ratio of oxidized albumin (human nonmercaptalbumin, HNA). Patients were administered 400 mg rifaximin 3 times/day for 3 months, and laboratory data were assessed at baseline and during observation. Among the eight patients, three were men; the median age and body mass index were 70 years and 26.4 kg/m², respectively. The median HNA and serum ammonia levels at baseline were 41% and 143 μg/dL, respectively. After rifaximin therapy, HNA showed a decreasing tendency (median; from 41% to 36%, p = 0.321), but serum albumin levels showed no significant change (from 3.5 g/dL to 3.5 g/dL, p = 1.00); serum ammonia levels significantly reduced (median: 143 μg/dL to 76 μg/dL, p = 0.015). Thus, rifaximin reduces serum ammonia levels and may improve circulating albumin structure in patients with cirrhosis. Further large-scale studies are required to confirm these preliminary results.

Why Do the Mechanistic Actions of Albumin Not Translate Into Tangible Clinical Benefits?

Albumin has only reduced crude mortality in one randomized controlled trial conducted to date. This raises the question as to why potentially beneficial oncotic and pleiotropic properties of albumin do not consistently translate into clinically important outcomes. Four postulated explanations are provided as to why the theoretical advantages of albumin are not apparent in clinical trials: diminished oncotic action due to leakage of albumin from the intravascular compartment, modification of the pleiotropic properties of albumin both in vitro and in vivo, the ability of other plasma proteins to take over the major functions of albumin, and possible adverse effects.

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

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

A randomized-controlled trial comparing 20% albumin to plasmalyte in patients with cirrhosis and sepsis-induced hypotension [ALPS trial]

BACKGROUND & AIMS

The choice of resuscitation fluid in patients with cirrhosis and sepsis-induced hypotension is unclear. 5% albumin was superior to normal saline in the FRISC study. We compared the efficacy and safety of 20% albumin, which has greater oncotic properties, to plasmalyte in reversing sepsis-induced hypotension.

METHODS

Critically ill patients with cirrhosis underwent open-label randomization to receive either 20% albumin (0.5-1.0 g/kg over 3 hours; n = 50) or plasmalyte (30 ml/kg over 3 hours, n = 50). The primary endpoint of the study was the attainment of mean arterial pressure (MAP) above 65 mmHg at 3 hours.

RESULTS

Baseline characteristics were comparable in albumin and plasmalyte groups; arterial lactate (6.16±3.18 mmol/L vs. 6.38±4.77 mmol/L; p = 0.78), MAP (51.4±6.52 mmHg vs. 49.9±4.45 mmHg; p = 0.17) and SOFA score (10.8±2.96 vs. 11.1±4.2; p = 0.68), respectively. Most patients were alcoholics (39%) and had pneumonia (40%). In the intention-to-treat analysis, albumin was superior to plasmalyte in achieving the primary endpoint (62% vs. 22%; p <0.001). A faster decline in arterial lactate (p = 0.03), a reduced need for dialysis (48% vs. 62%; p = 0.16), and a longer time to initiation of dialysis (in hours) (68.13±47.79 vs. 99.7± 63.4; p = 0.06) were seen with albumin. However, the 28-day mortality rate was not different (58% vs. 62%, p = 0.57) and treatment had to be discontinued in 11 (22%) patients in the albumin group due to adverse effects compared to no discontinuations in the plasmalyte group.

CONCLUSION

In patients with cirrhosis and sepsis-induced hypotension, 20% albumin leads to a faster improvement in hemodynamics and lactate clearance than plasmalyte, while 28-day survival was similar. However, patients on 20% albumin need to be closely monitored as it was more often associated with pulmonary complications.

CLINICAL TRIAL REGISTRATION

NCT02721238.

LAY SUMMARY

The current randomized-controlled trial performed in critically ill patients with cirrhosis and sepsis-induced hypotension highlights that 20% albumin restores arterial pressure more quickly but causes more pulmonary complications than plasmalyte. The impact on renal functions was also modest. These effects did not result in improvement in survival at 28 days. Plasmalyte is safer and well-tolerated and can be considered for volume resuscitation in patients with cirrhosis and sepsis-induced hypotension.

Structural changes of proteins in liver cirrhosis and consequential changes in their function

The liver is the site of synthesis of the majority of circulating proteins. Besides initial polypeptide synthesis, sophisticated machinery is involved in the further processing of proteins by removing parts of them and/or adding functional groups and small molecules tailoring the final molecule to suit its physiological purpose. Posttranslational modifications (PTMs) design a network of molecules with the common protein ancestor but with slightly or considerably varying activity/localization/purpose. PTMs can change under pathological conditions, giving rise to aberrant or overmodified proteins. Undesired changes in the structure of proteins most often accompany undesired changes in their function, such as reduced activity or the appearance of new effects. Proper protein processing is essential for the reactions in living beings and crucial for the overall quality control. Modifications that occur on proteins synthesized in the liver whose PTMs are cirrhosis-related are oxidation, nitration, glycosylation, acetylation, and ubiquitination. Some of them predominantly affect proteins that remain in liver cells, whereas others predominantly occur on proteins that leave the liver or originate from other tissues and perform their function in the circulation. Altered PTMs of certain proteins are potential candidates as biomarkers of liver-related diseases, including cirrhosis. This review will focus on PTMs on proteins whose structural changes in cirrhosis exert or are suspected to exert the most serious functional consequences.

Bile Acid-Drug Interaction via Organic Anion-Transporting Polypeptide 4C1 Is a Potential Mechanism of Altered Pharmacokinetics of Renally Excreted Drugs

Patients with liver diseases not only experience the adverse effects of liver-metabolized drugs, but also the unexpected adverse effects of renally excreted drugs. Bile acids alter the expression of renal drug transporters, however, the direct effects of bile acids on drug transport remain unknown. Renal drug transporter organic anion-transporting polypeptide 4C1 (OATP4C1) was reported to be inhibited by chenodeoxycholic acid. Therefore, we predicted that the inhibition of OATP4C1-mediated transport by bile acids might be a potential mechanism for the altered pharmacokinetics of renally excreted drugs. We screened 45 types of bile acids and calculated the IC50, Ki values, and bile acid−drug interaction (BDI) indices of bile acids whose inhibitory effect on OATP4C1 was >50%. From the screening results, lithocholic acid (LCA), glycine-conjugated lithocholic acid (GLCA), and taurine-conjugated lithocholic acid (TLCA) were newly identified as inhibitors of OATP4C1. Since the BDI index of LCA was 0.278, LCA is likely to inhibit OATP4C1-mediated transport in clinical settings. Our findings suggest that dose adjustment of renally excreted drugs may be required in patients with renal failure as well as in patients with hepatic failure. We believe that our findings provide essential information for drug development and safe drug treatment in clinics.

Clostridioides difficile Infection in Liver Cirrhosis: A Concise Review

Clostridium difficile is a Gram-positive bacillus with fecal-oral transmission and is currently one of the most common nosocomial infections worldwide, which was renamed Clostridioides difficile in 2016. Clostridioides difficile infection (CDI) is a prevalent infection in cirrhosis and negatively affects prognosis. This study aimed to provide a concise review with clinical practice implications. The prevalence of CDI in cirrhotic patients increases, while the associated mortality decreases. Multiple groups of risk factors increase the likelihood of CDI in patients with cirrhosis, such as antibiotic use, the severity of cirrhosis, some comorbidities, and demographic aspects. Treatment in the general population is currently described in the latest guidelines. In patients with cirrhosis, rifaximin and lactulose have been shown to reduce CDI risk due to their modulatory effects on the intestinal flora, although conflicting results exist. Fecal microbiota transplantation (FMT) as a treatment for the second or subsequent CDI recurrences has demonstrated a good safety and efficacy in cirrhosis and CDI. Future validation in more prospective studies is needed. Screening of asymptomatic patients appears to be discouraged for the prevention currently, with strict hand hygiene and cleaning of the ward and medical equipment surfaces being the cornerstone of minimizing transmission.

Long-term albumin treatment in patients with cirrhosis and ascites

Although proposed for the first time several decades ago, the possibility that long-term human albumin could be effective for the treatment of patients with cirrhosis and ascites has become a topic of scientific and clinical discussion in the last decade. Long-term albumin administration represents a completely different treatment perspective compared to acute or short-term uses of albumin. Results from the ANSWER and the MACHT studies indicate that long-term albumin treatment can be effective, safe and able to modify the course of the disease provided that albumin is given at a sufficient dose and for a sufficient time to restore physiological levels and functions of the circulating molecule, which are compromised, at least partially, in patients with decompensated cirrhosis. Further clinical studies and randomised trials are warranted to confirm the clinical benefits of long-term albumin therapy. Important areas for further research include determining the precise target population, the biomarkers of response, the optimal dose and frequency of albumin infusions, the stopping rules, and the cost-effectiveness of treatment in different healthcare systems across the world, particularly in those where the logistical issues and costs related to the periodic intravenous infusions may represent an important limitation to the implementation of this innovative approach in clinical practice. In this review, we will critically analyse the available data on long-term albumin treatment, focusing on the differences that exist between studies, the controversial issues and the future perspectives.

Therapeutic solutions of human albumin - The possible effect of process-induced molecular alterations on clinical efficacy and safety

Human albumin solutions were developed as therapeutic during the Second World War to address blood loss due to battlefield injury. This indication was based on the recognition that albumin provided most of the oncotic capacity of human plasma. For the succeeding sixty years, this formed the basis for the use of albumin in traumatology and emergency medicine. In more recent times, the pharmacological properties arising from albumin's complex structure have become a focus of attention by clinical researchers. In particular, albumin, through anti-inflammatory and anti-oxidant properties, has been proposed as an agent for the treatment of sepsis, cirrhosis and other inflammatory states. Some evidence for these indications has accrued from a number of small clinical trials and observational studies. These studies have not been confirmed in other large trials. Together with other investigators, we have shown that the process of plasma fractionation results in alterations in the structure of albumin, including those parts of the molecule involved in anti-oxidant and anti-inflammatory effects. Albumin products from diverse manufacturers show heterogeneity in their ability to address these effects. In this article, we review the historical development of albumin solutions, pointing out the variations in fractionation chemistries which different manufacturers have adopted. We suggest ways by which the manufacturing processes have contributed to variations in the physico-chemical properties of molecule. We review the outcomes of clinical studies assessing the role of albumin in ameliorating conditions such as sepsis and cirrhosis, and we speculate as to the extent which heterogeneity in the products may have contributed to variable clinical outcomes. Finally, we argue for a change in the perception of the plasma product industry and its regulatory overseers. Historically, albumin has been viewed as a generic commodity, with different preparations being interchangeable in their clinical application. We suggest that this implied biosimilarity is not necessarily applicable for different albumin solutions. The use of albumin, in indications other than its historical role as a plasma expander, can only be validated by clinical investigation of each separate albumin product.

HSA-Binding Prodrugs-Based Nanoparticles Endowed with Chemo and Photo-Toxicity against Breast Cancer

Exploiting the tumor environment features (EPR effect, elevated glutathione, reactive oxygen species levels) might allow attaining a selective and responsive carrier capable of improving the therapeutic outcome. To this purpose, the in situ covalent binding of drugs and nanoparticles to circulating human serum albumin (HSA) might represent a pioneering approach to achieve an effective strategy. This study describes the synthesis, in vitro and in vivo evaluation of bioresponsive HSA-binding nanoparticles (MAL-PTX₂S@Pba), co-delivering two different paclitaxel (PTX) prodrugs and the photosensitizer pheophorbide a (Pba), for the combined photo- and chemo-treatment of breast cancer. Stable and reproducible MAL-PTX₂S@Pba nanoparticles with an average diameter of 82 nm and a PTX/Pba molar ratio of 2.5 were obtained by nanoprecipitation. The in vitro 2D combination experiments revealed that MAL-PTX₂S@Pba treatment induces a strong inhibition of cell viability of MDA-MB-231, MCF7 and 4T1 cell lines, whereas 3D experiments displayed different trends: while MAL-PTX₂S@Pba effectiveness was confirmed against MDA-MB-231 spheroids, the 4T1 model exhibited marked resistance. Lastly, despite using a low PTX-PDT regimen (e.g., 8.16 mg/Kg PTX and 2.34 mg/Kg Pba), our formulation showed to foster primary tumor reduction and curb lung metastases growth in 4T1 tumor-bearing mice, thus setting the basis for further preclinical validations.

Association of Low Serum Albumin Level with Higher Hepatocellular Carcinoma Recurrence in Patients with Hepatitis B Virus Pre-S2 Mutant after Curative Surgical Resection

Hepatocellular carcinoma (HCC) is, globally, one of the most prevalent and deadly human cancers; despite curative surgical resection, its high recurrence rate after surgery remains a large threat, resulting in poor patient survival. The hepatitis B virus (HBV) pre-S2 mutant that harbors deletions spanning the pre-S2 gene segment has emerged as an important oncoprotein for HCC development and a valuable prognostic biomarker for HCC recurrence; however, its relationship with clinicopathological factors is largely unexplored. In this study, the correlation of the deletion spanning the pre-S2 gene segment with clinicopathological factors and the association of such correlation with HCC recurrence after curative surgical resection were examined in HBV-related HCC patients. Inverse correlation between serum albumin level and the deletion spanning the pre-S2 gene segment was identified. HCC patients with the presence of the deletion spanning the pre-S2 gene segment and a low serum albumin level were associated with higher HCC recurrence than patients with either factor alone or neither factor were. Moreover, a combination of the serum albumin level and the deletion spanning the pre-S2 gene segment exhibited better performance than that of either factor alone in predicting HCC recurrence. Collectively, this study shows an association of low serum albumin level with pre-S2 mutant-positive HCC patients, and validates the prognostic value of this association in identifying patients with higher HCC recurrence after curative surgical resection.

Nutrition in Patients with Type 2 Diabetes: Present Knowledge and Remaining Challenges

Unhealthy behaviours, including diet and physical activity, coupled with genetic predisposition, drive type 2 diabetes (T2D) occurrence and severity; the present review aims to summarise the most recent nutritional approaches in T2D, outlining unmet needs. Guidelines consistently suggest reducing energy intake to counteract the obesity epidemic, frequently resulting in sarcopenic obesity, a condition associated with poorer metabolic control and cardiovascular disease. Various dietary approaches have been proposed with largely similar results, with a preference for the Mediterranean diet and the best practice being the diet that patients feel confident of maintaining in the long term based on individual preferences. Patient adherence is indeed the pivotal factor for weight loss and long-term maintenance, requiring intensive lifestyle intervention. The consumption of nutritional supplements continues to increase even if international societies do not support their systematic use. Inositols and vitamin D supplementation, as well as micronutrients (zinc, chromium, magnesium) and pre/probiotics, result in modest improvement in insulin sensitivity, but their use is not systematically suggested. To reach the desired goals, patients should be actively involved in the collaborative development of a personalised meal plan associated with habitual physical activity, aiming at normal body weight and metabolic control.